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Abundant in unpolluted ponds and streams, planarians prey on smaller animals or feed on? | unidentified animals | algae | fungi | dead animals | |
What does parasitic mean? | symbiotic | mutual benefit | welcome guest | lives in host | Other types of flatworms are parasitic. That means they live inside another organism, called a host, in order to get the food and energy they need. For example, tapeworms have a head-like area with tiny hooks and suckers (known as the scolex ) that help the worm attach to the intestines of an animal host ( Figure below ). There are over 11,000 species of parasitic flatworms. |
What scientist constructed a tree diagram, separating living organisms into three domains? | Mendel | Gibbs | CT Fletcher | carl woese | Figure 1.17 This phylogenetic tree was constructed by microbiologist Carl Woese using data obtained from sequencing ribosomal RNA genes. The tree shows the separation of living organisms into three domains: Bacteria, Archaea, and Eukarya. Bacteria and Archaea are prokaryotes, single-celled organisms lacking intracellular organelles. (credit: Eric Gaba; NASA Astrobiology Institute). |
Most of the genes in the eukaryotic cell are found where? | the mitochondria | the vacuoles | the cell wall | the nucleus | |
What are known as the building blocks of proteins? | bases | organism acids | protein acids | amino acids | Introduction Since the rediscovery of Mendel’s work in 1900, the definition of the gene has progressed from an abstract unit of heredity to a tangible molecular entity capable of replication, expression, and mutation (Figure 15.1). Genes are composed of DNA and are linearly arranged on chromosomes. Genes specify the sequences of amino acids, which are the building blocks of proteins. In turn, proteins are responsible for orchestrating nearly every function of the cell. Both genes and the proteins they encode are absolutely essential to life as we know it. |
What are the three types of muscle tissue in the body? | proliferating , cardiac , smooth | spongy, cardiac, skeletal | topography , cardiac , smooth | skeletal, cardiac, smooth | 10.1 Overview of Muscle Tissues Muscle is the tissue in animals that allows for active movement of the body or materials within the body. There are three types of muscle tissue: skeletal muscle, cardiac muscle, and smooth muscle. Most of the body’s skeletal muscle produces movement by acting on the skeleton. Cardiac muscle is found in the wall of the heart and pumps blood through the circulatory system. Smooth muscle is found in the skin, where it is associated with hair follicles; it also is found in the walls of internal organs, blood vessels, and internal passageways, where it assists in moving materials. |
The white mountains in new hampshire are part of what province? | antarctic | montreal | geologic | appalachian | The White Mountains in New Hampshire are part of the Appalachian province. The mountains are only around 6,000 feet high. |
What is the ratio of the uncertainty to the measured value, multiplied by one-hundred called? | percent inconsistency | variable uncertainty | amount uncertainty | percent uncertainty | To express the uncertainty in a measurement, we can calculate percent uncertainty . Percent uncertainty is the ratio of the uncertainty to the measured value, multiplied by one-hundred. For instance, the percent uncertainty associated with the measurement of (52.9 ± 0.5 mL), would be. |
What is produced by the sebaceous glands? | progesterone | pheromone | sperm | sebum | Structures in the dermis include hair follicles and sebaceous glands, which produce sebum. |
What do you call vesicle transport into the cell? | dialysis | passive transport | metastasis | endocytosis | Vesicle transport into the cell is called endocytosis. The cell membrane engulfs the substance. Then a vesicle pinches off from the membrane and carries the substance into the cell. |
What are daily changes in the level of ocean water called? | currents | waves | floods | tides | Tides are daily changes in the level of ocean water. They are caused mainly by the pull of the Moon’s gravity on Earth and its oceans. The Sun’s gravity also influences tides. |
What is the name of the narrow tube that begins at the stomach and ends at the large intestine? | small tissues | small stomach | pancreas | small intestine | The small intestine is a narrow tube that starts at the stomach and ends at the large intestine. In adults, it’s about 7 meters (23 feet) long. Most chemical digestion and almost all nutrient absorption take place in the small intestine. |
What is the term for how close a measurement is to the true value? | correctness | frequency | validity | accuracy | Accuracy is how close a measurement is to the true value. For example, 66 mL is a fairly accurate measurement of the liquid in Figure above . |
What are the two most abundant elements in the universe? | oxygen and carbon | hydrogen and oxygen | nitrogen and carbon | hydrogen and helium | Hydrogen and helium are the most abundant elements in the universe. |
What is the term for a close relationship between two species in which at least one species benefits. | endosymbiosis | extosis | candiasis | symbiosis | Symbiosis is a close relationship between two species in which at least one species benefits. Types of symbiosis include mutualism, parasitism, and commensalism. |
Atomic emission spectra are produced when excited electrons return to what state? | side state | orbital state | work state | ground state | Atomic emission spectra are produced when excited electrons return to ground state. |
The lungs perform gas exchange using air and what fluid, which is coming and going from the heart? | saliva | mucus | water | blood | Blood Supply The major function of the lungs is to perform gas exchange, which requires blood from the pulmonary circulation. This blood supply contains deoxygenated blood and travels to the lungs where erythrocytes, also known as red blood cells, pick up oxygen to be transported to tissues throughout the body. The pulmonary artery is an artery that arises from the pulmonary trunk and carries deoxygenated, arterial blood to the alveoli. The pulmonary artery branches multiple times as it follows the bronchi, and each branch becomes progressively smaller in diameter. One arteriole and an accompanying venule supply and drain one pulmonary lobule. As they near the alveoli, the pulmonary arteries become the pulmonary capillary network. The pulmonary capillary network consists of tiny vessels with very thin walls that lack smooth muscle fibers. The capillaries branch and follow the bronchioles and structure of the alveoli. It is at this point that the capillary wall meets the alveolar wall, creating the respiratory membrane. Once the blood is oxygenated, it drains from the alveoli by way of multiple pulmonary veins, which exit the lungs through the hilum. |
In addition to glucose, what gas is used during cellular respiration? | nitrogen | methane | hydrogen | oxygen | Cellular respiration uses oxygen in addition to glucose. It releases carbon dioxide and water as waste products. Cellular respiration actually "burns" glucose for energy. However, it doesn't produce light or intense heat like burning a candle or log. Instead, it releases the energy slowly, in many small steps. The energy is used to form dozens of molecules of ATP. |
Which germ layers are essential for animal embryos to grow and develop into a body? | cytoplasm and chloroplasm | histone and melatonin | keratinocytes , ectoderm , mesoderm | endoderm, ectoderm, mesoderm | The three germ layers are the endoderm, the ectoderm, and the mesoderm. Cells in each germ layer differentiate into tissues and embryonic organs. The ectoderm gives rise to the nervous system and the epidermis, among other tissues. The mesoderm gives rise to the muscle cells and connective tissue in the body. The endoderm gives rise to the gut and many internal organs. Organogenesis Gastrulation leads to the formation of the three germ layers that give rise during further development to the different organs in the animal body. This process is called organogenesis. Organs develop from the germ layers through the process of differentiation. During differentiation, the embryonic stem cells express specific sets of genes that will determine their ultimate cell type. For example, some cells in the ectoderm will express the genes specific to skin cells. As a result, these cells will take on the shape and characteristics of epidermal cells. The process of differentiation is regulated by location-specific chemical signals from the cell’s embryonic environment that sets in play a cascade of events that regulates gene expression. |
Scrubbers and catalytic converters are examples of technologies that change what into harmless compounds? | mutations | contaminants | toxins | pollutants | Some of the pollutants from fossil fuels can be filtered out of exhaust before it is released into the air ( Figure below ). Other pollutants can be changed to harmless compounds before they are released. Two widely used technologies are scrubbers and catalytic converters. |
What is the weighted average of the masses of all isotopes of an element called? | weight mass | cell mass | light mass | atomic mass | The atomic mass is the weighted average of the masses of all isotopes of an element. |
The ability of a water spider to walk across a body of water is an example of what? | magnetism | high density | low gravity | surface tension | The surface tension of water is illustrated by a number of common occurrences. For example, water spiders are able to walk across bodies of water because of surface tension. Even though the spiders are denser than water, they do not sink, because the small amount of weight pressing down on the surface is not enough to break the strong hydrogen bonds that hold the surface together. |
What are compounds with the same molecular formula but different structures and properties called? | polymers | substrates | monomers | isomers | |
What happens when the blood cannot reach the heart because a blood vessel is blocked? | pass out | fast heart beat | heart burn | heart attack | A heart attack happens when the blood cannot reach the heart because a blood vessel is blocked. If cardiac muscle is starved of oxygen for more than roughly five minutes, it will die. Cardiac muscle cells cannot be replaced, so once they die, they are dead forever. Coronary heart disease is the leading cause of death of adults in the United States. The image below shows the way in which a blocked coronary artery can cause a heart attack and cause part of the heart muscle to die ( Figure below ). Maybe one day stem cells will be used to replace dead cardiac muscle cells. |
What kind of solid is characterized by an unorganized and unpredictable structure? | porous | magnetic | aqueous | amorphous | When water freezes in a non-crystalline, amorphous form as frost, the water molecules are fixed in place, but not in a regular, repeating pattern. Frost and other amorphous solids are characterized by their unorganized and unpredictable structure. Because ice comes in both amorphous and crystalline forms, there are differences in the physical properties of ice such as its hardness and density. |
An object with more mass has greater thermal energy than an object with less mass because it has more what? | gravity | molecules | ions | atoms | 5. Thermal energy is the energy of moving atoms of matter. All matter has thermal energy because atoms of all matter are constantly moving. An object with more mass has greater thermal energy than an object with less mass because it has more atoms. |
Ether molecules have an oxygen atom and can engage in hydrogen bonding with which other molecules? | lipids | carbon dioxides | proteins | water | Ether molecules have an oxygen atom and can engage in hydrogen bonding with water molecules. An ether molecule has about the same solubility in water as the alcohol that is isomeric with it. |
What basic structures of the nervous system innervate the muscles of the respiratory system and are responsible for controlling and regulating pulmonary ventilation? | ions | toxins | enzymes | neurons | Neurons that innervate the muscles of the respiratory system are responsible for controlling and regulating pulmonary ventilation. The major brain centers involved in pulmonary ventilation are the medulla oblongata and the pontine respiratory group (Figure 22.20). |
Pollutants in surface water can filter into the ground and enter a what? | combustion aquifer | hydro plant | turbine | groundwater aquifer | Pollutants in surface water can filter into the ground and enter a groundwater aquifer. Irrigation water can bring pesticides and other chemicals. Water can seep through landfills. Tanks of gasoline stored underground can leak. |
What is the most common cause of dwarfism? | retinopathy | deformity | hypothyroidism | achondroplasia | Whereas cystic fibrosis, Tay-Sachs, and phenylketonuria are all autosomal recessive disorders, achondroplasia is an autosomal dominant disorder. Achondroplasia is the most common cause of dwarfism in humans. Achondroplasia is a result of an autosomal dominant mutation in the fibroblast growth factor receptor gene 3 (FGFR3), which causes an abnormality of cartilage formation. FGFR3 normally has a negative regulatory effect on bone growth. In achondroplasia, the mutated form of the receptor is constitutively active (constantly “turned on”) and this leads to severely shortened bones. Individuals with achondroplasia are heterozygous for the mutation (one mutant copy, one normal copy). Homozygous for the achondroplasia mutation is lethal prior to birth or shortly after birth. |
What describes how much matter is in a certain amount of space? | viscosity | volume | mass | density | Density describes how much matter is in a certain amount of space. Substances that have more matter packed into a given space have higher densities. The water in a drinking glass has the same density as the water in a bathtub or swimming pool. All substances have characteristic densities, which does not depend on how much of a substance you have. |
Axons pass what on to other cells? | calcium impulses | synthesis impulses | myelin impulses | nerve impulses | The cell body contains the nucleus and other organelles. Dendrites and axons connect to the cell body, similar to rays coming off of the sun. Dendrites receive nerve impulses from other cells. Axons pass the nerve impulses on to other cells. A single neuron may have thousands of dendrites, so it can communicate with thousands of other cells but only one axon. The axon is covered with a myelin sheath , a fatty layer that insulates the axon and allows the electrical signal to travel much more quickly. The node of Ranvier is any gap within the myelin sheath exposing the axon, and it allows even faster transmission of a signal. |
Sister chromatids separate and move to opposite poles of the cell in the third phase of what process? | meiosis | cytokinesis | epistasis | mitosis | third phase of mitosis during which sister chromatids separate and move to opposite poles of the cell. |
What is the distance that sound waves travel in a given amount of time called? | force of sound | velocity of sound | momentum of sound | speed of sound | The speed of sound is the distance that sound waves travel in a given amount of time. The speed of sound in dry air at 20 °C is 343 meters per second. |
What would you call a relationship where the bacteria benefit and and the other organism is harmed? | symbiotic | pathology | fungi | parasitism | Other bacteria are parasitic and can cause illness. In parasitism , the bacteria benefit, and the other organism is harmed. Harmful bacteria will be discussed in another concept. |
What is the supply of water to land or crops to help growth called? | precipitation | drainage | absorbtion | irrigation | Some of the problems associated with intensive irrigation include all but. |
What form of matter has neither a definite shape nor a definite volume? | liquid | plasma | solid | gas | A gas is a form of matter that has neither a definite shape nor a definite volume. A gas takes up the shape and volume of its container. This is because the particles of a gas are very far apart from one another compared to the particles that make up solids and liquids. Gases are easily compressed because of the large spaces in between gas particles. Gas particles are often invisible, but they can be detected in various ways, such as the light emitted when an electric current is passed through a sample of a gas ( Figure below ). |
Which stage has already been completed by the time sea urchin eggs are released from the female? | mitoses | fetus | secondary | meiosis | |
Unlike pure substances, mixtures have a what? | complex composition | efficient composition | unique composition | variable composition | When two or more pure substances are combined together, a mixture is formed. Unlike pure substances, mixtures have a variable composition. Variable composition indicates that the relative proportions of the mixtures components may vary, and they can be separated by physical methods. There are two main types of mixtures. |
What process does not cause a rock to melt completely, instead causing the minerals to change by heat or pressure? | igneous extrusion | sedimentation | oxidation | metamorphism | Metamorphism does not cause a rock to melt completely. It only causes the minerals to change by heat or pressure. |
A disaccharide is a pair of monosaccharides. disaccharides are formed via dehydration synthesis, and the bond linking them is referred to as a glycosidic bond (glyco- = “sugar”). three disaccharides (shown in figure 2.19) are important to humans. these are sucrose, commonly referred to as table sugar; lactose, or milk sugar; and maltose, or this? | sucralose | fruit sugar | saccharin | malt sugar | Disaccharides A disaccharide is a pair of monosaccharides. Disaccharides are formed via dehydration synthesis, and the bond linking them is referred to as a glycosidic bond (glyco- = “sugar”). Three disaccharides (shown in Figure 2.19) are important to humans. These are sucrose, commonly referred to as table sugar; lactose, or milk sugar; and maltose, or malt sugar. As you can tell from their common names, you consume these in your diet; however, your body cannot use them directly. Instead, in the digestive tract, they are split into their component monosaccharides via hydrolysis. |
At what age is skeletal maturity reached by humans? | 15 | 40 | 30 | 20 | Bones become increasingly ossified and grow larger during fetal development, childhood, and adolescence. When skeletal maturity is reached at about age 20, no additional growth in bone length can occur. |
What is most of earth's surface covered with? | silicon | insects | sand | water | The outer planets in the solar system are giant balls of swirling gas. Earth and the other inner planets are relatively small, dense, and rocky. Most of Earth’s surface is covered with water. As far as we know, Earth is also the only planet that has liquid water. Earth's atmosphere has oxygen. The water and oxygen are crucial to life as we know it. Earth appears to be the only planet in the solar system with living creatures. You can learn more about the planets in the Our Solar System chapter. |
What is the sac-like organ of the body that is important for both mechanical and chemical digestion? | spleen | gall bladder | kidney | stomach | The stomach is a sac-like organ in which food is further digested both mechanically and chemically. (To see an animation of how the stomach digests food, go to the link below. ) Churning movements of the stomach’s thick, muscular walls complete the mechanical breakdown of food. The churning movements also mix food with digestive fluids secreted by the stomach. One of these fluids is hydrochloric acid. It kills bacteria in food and gives the stomach the low (acidic) pH needed by digestive enzymes that work in the stomach. The main enzyme is pepsin , which chemically digests protein. |
All chemical reactions require what to get started? | primary energy | conductivity energy | spiked energy | activation energy | Some chemical reactions release energy, whereas other chemical reactions absorb energy. All chemical reactions require activation energy to get started. |
Mitosis is nuclear division during which duplicated chromosomes are segregated and distributed into what? | woman nuclei | father nuclei | long nuclei | daughter nuclei | Figure 6.3 A cell moves through a series of phases in an orderly manner. During interphase, G1 involves cell growth and protein synthesis, the S phase involves DNA replication and the replication of the centrosome, and G2 involves further growth and protein synthesis. The mitotic phase follows interphase. Mitosis is nuclear division during which duplicated chromosomes are segregated and distributed into daughter nuclei. Usually the cell will divide after mitosis in a process called cytokinesis in which the cytoplasm is divided and two daughter cells are formed. |
Movement of water and minerals in the xylem solutes, pressure, gravity, and matric potential are all important for what? | increase water transport | produce water transport | Moving Water Transport | plant water transport | Movement of Water and Minerals in the Xylem Solutes, pressure, gravity, and matric potential are all important for the transport of water in plants. Water moves from an area of higher total water potential (higher Gibbs free energy) to an area of lower total water potential. Gibbs free energy is the energy associated with a chemical reaction that can be used to do work. This is expressed as ΔΨ. Transpiration is the loss of water from the plant through evaporation at the leaf surface. It is the main driver of water movement in the xylem. Transpiration is caused by the evaporation of water at the leaf–atmosphere interface; it creates negative pressure (tension) equivalent to –2 MPa at the leaf surface. This value varies greatly depending on the vapor pressure deficit, which can be negligible at high relative humidity (RH) and substantial at low RH. Water from the roots is pulled up by this tension. At night, when stomata shut and transpiration stops, the water is held in the stem and leaf by the adhesion of water to the cell walls of the xylem vessels and tracheids, and the cohesion of water molecules to each other. This is called the cohesion–tension theory of sap ascent. Inside the leaf at the cellular level, water on the surface of mesophyll cells saturates the cellulose microfibrils of the primary cell wall. The leaf contains many large intercellular air spaces for the exchange of oxygen for carbon dioxide, which is required for photosynthesis. The wet cell wall is exposed to this leaf internal air space, and the water on the surface of the cells evaporates into the air spaces, decreasing the thin film on the surface of the mesophyll cells. This decrease creates a greater tension on the water in the mesophyll cells (Figure 30.34), thereby increasing the pull on the water in the xylem vessels. The xylem vessels and tracheids are structurally adapted to cope with large changes in pressure. Rings in the vessels maintain their tubular shape, much like the rings on a vacuum cleaner hose keep the hose open while it is under pressure. Small perforations between vessel elements reduce the number and size of gas bubbles that can form via a process called cavitation. The formation of gas bubbles in xylem interrupts the continuous stream of water from the base to the top of the. |
The temperature of the box is related to the average speed of what? | earth | air | light | molecules | The temperature of the box is related to the average speed of the molecules. Use momentum principles to relate temperature to pressure. Explain conceptually, in words rather than with equations. |
What are organisms that eat just one type of food? | devotees | gluttons | hedonists | specialists | Specialists are organisms that eat just one type of food. Birds that are specialists include ospreys, which eat only live fish. You can see an osprey in Figure below . The osprey’s feet are very well-adapted for catching fish. Its eyes are also well-adapted for seeing fish under the water. Its beak is well suited for gripping and ripping into fish flesh. Ospreys are so well-adapted to catching fish that they can't catch anything else!. |
Mechanisms for establishing cellular asymmetries include morphogen gradients, localized determinants, and what other type of interactions? | electromagnetic | reductive | conductive | inductive | |
Biodiversity hot spots are prime candidates for protection because they are prone to what species fate? | accumulation | mutation | reduction | extinction | |
What are single-celled or colonial organisms that do not have membranebound nuclei? | eukaryotes | arthropods | viruses | prokaryotes | Watch this video (http://openstaxcollege. org/l/rotating_DNA) that animates the three-dimensional structure of the DNA molecule shown in Figure 1.15. Some cells contain aggregates of macromolecules surrounded by membranes; these are called organelles. Organelles are small structures that exist within cells. Examples of organelles include mitochondria and chloroplasts, which carry out indispensable functions: mitochondria produce energy to power the cell, while chloroplasts enable green plants to utilize the energy in sunlight to make sugars. All living things are made of cells; the cell itself is the smallest fundamental unit of structure and function in living organisms. (This requirement is why viruses are not considered living: they are not made of cells. To make new viruses, they have to invade and hijack the reproductive mechanism of a living cell; only then can they obtain the materials they need to reproduce. ) Some organisms consist of a single cell and others are multicellular. Cells are classified as prokaryotic or eukaryotic. Prokaryotes are single-celled or colonial organisms that do not have membranebound nuclei; in contrast, the cells of eukaryotes do have membrane-bound organelles and a membrane-bound nucleus. In larger organisms, cells combine to make tissues, which are groups of similar cells carrying out similar or related functions. Organs are collections of tissues grouped together performing a common function. Organs are present not only. |
Differences in density between water and air lead to differences in what? | energy | resistance | sound | pressure | Differences in density between water and air lead to differences in pressure. |
What organizational tool, arguably the best in all of science, lists all the known chemical elements, arranged by atomic number? | spreadsheet | tide table | logic table | periodic table | Appendix: Periodic Table of the Elements In this chapter, we present some data on the chemical elements. The periodic table, introduced in Chapter 3 "Atoms, Molecules, and Ions", lists all the known chemical elements, arranged by atomic number (that is, the number of protons in the nucleus). The periodic table is arguably the best tool in all of science; no other branch of science can summarize its fundamental constituents in such a concise and useful way. Many of the physical and chemical properties of the elements are either known or understood based on their positions on the periodic table. Periodic tables are available with a variety of chemical and physical properties listed in each element’s box. What follows here is a more complex version of the periodic table than what was presented inChapter 3 "Atoms, Molecules, and Ions". The Internet is a great place to find periodic tables that contain additional information. One item on most periodic tables is the atomic mass of each element. For many applications, only one or two decimal places are necessary for the atomic mass. However, some applications (especially nuclear chemistry; see Chapter 15 "Nuclear Chemistry") require more decimal places. The atomic masses in Table 17.1 "The Basics of the Elements of the Periodic Table" represent the number of decimal places recognized by the International Union of Pure and Applied Chemistry, the worldwide body that develops standards for chemistry. The atomic masses of some elements are known very precisely, to a large number of decimal places. The atomic masses of other elements, especially radioactive elements, are not known as precisely. Some elements, such as lithium, can have varying atomic masses depending on how their isotopes are isolated. The web offers many interactive periodic table resources. For example, seehttp://www. ptable. |
Solvation involves surrounding ions with what? | passive particles | proteins | molecules | solvent particles | Solvation involves surrounding ions with solvent particles. |
The appendicular skeleton includes all bones of the upper and lower limbs, plus the bones that attach each limb to the what? | compressed skeleton | literal skeleton | dynamic skeleton | axial skeleton | The Appendicular Skeleton The appendicular skeleton includes all bones of the upper and lower limbs, plus the bones that attach each limb to the axial skeleton. There are 126 bones in the appendicular skeleton of an adult. The bones of the appendicular skeleton are covered in a separate chapter. |
Cow manure can have a second life as a source of what gas? | ethanol | freon | hydrogen | methane | Cow manure can have a second life as a source of methane gas, which can be converted to electricity. Not only that food scraps can also be converted into green energy. |
Eggs reside in the mesohyl, but sperm are carried out of the sponge by what? | ion channels | air current | phloem | water current | |
Population size influences the chances of a species surviving, with very small populations generally at greatest risk of what fate? | mutation | adaptation | accumulation | extinction | Population size is the number of individuals in a population. For example, a population of insects might consist of 100 individual insects, or many more. Population size influences the chances of a species surviving or going extinct. Generally, very small populations are at greatest risk of extinction. However, the size of a population may be less important than its density. |
Sound is the transfer of energy from a vibrating object in waves that travel through what? | water | light | time | matter | Sound is the transfer of energy from a vibrating object in waves that travel through matter. |
Sterols are a subgroup of what? | antibiotics | nuclides | nutrients | steroids | Steroids (or sterols) have several functions. Sterols are a subgroup of steroids. The sterol cholesterol is an important part of cell membranes and plays other vital roles in the body. Cholesterol is a precursor to fat-soluble vitamins and steroid hormones. Steroid hormones include the male and female sex hormones. Sterols also have roles as second messengers in signalling pathways. |
Cardiac muscle is only found where? | abdomen | lung | brain | heart | Cardiac muscle also contracts and gets shorter. This muscle is found only in the heart. The sudden burst of contraction forces blood throughout your body. When the cardiac muscle relaxes, the heart fills with blood. This rhythmic contraction must continue for your whole life, luckily the heart muscle never gets tired. If your heart beats 75 times a minute, how many times does it beat in an hour? A day? A year? 85 years?. |
What process provides over 99 percent of the energy for life on earth? | fracking | farming | glycolysis | photosynthesis | Photosynthesis provides over 99 percent of the energy for life on earth. A much smaller group of autotrophs - mostly bacteria in dark or low-oxygen environments - produce food using the chemical energy stored in inorganic molecules such as hydrogen sulfide, ammonia, or methane. While photosynthesis transforms light energy to chemical energy, this alternate method of making food transfers chemical energy from inorganic to organic molecules. It is therefore called chemosynthesis , and is characteristic of the tubeworms shown in Figure below . Some of the most recently discovered chemosynthetic bacteria inhabit deep ocean hot water vents or “black smokers. ” There, they use the energy in gases from the Earth’s interior to produce food for a variety of unique heterotrophs: giant tube worms, blind shrimp, giant white crabs, and armored snails. Some scientists think that chemosynthesis may support life below the surface of Mars, Jupiter's moon, Europa, and other planets as well. Ecosystems based on chemosynthesis may seem rare and exotic, but they too illustrate the absolute dependence of heterotrophs on autotrophs for food. |
Unlike energy, what doesn’t need to be constantly added to ecosystems because it is recycled through ecosystems? | vapor | water | nutrients | matter | Unlike energy, matter doesn’t need to be constantly added to ecosystems. Instead, matter is recycled through ecosystems. Water and elements such as carbon and nitrogen that living things need are used over and over again. |
A colloid is a homogeneous mixture with medium-sized what? | molecules | atoms | solutions | particles | A colloid is a homogeneous mixture with medium-sized particles. Examples include homogenized milk and gelatin. The particles of a colloid are large enough to reflect light, so you can see them. But they are too small to settle or filter out of the mixture. |
What causes rivers to always flow downhill? | diffusion | slope | pressure | gravity | Currents are like rivers flowing through the ocean. Rivers always flow downhill because of gravity. What do you think causes ocean currents to flow?. |
What elements do water and hydrogen peroxide consist of? | hydrogen and helium | carbon and oxygen | calcium and oxygen | hydrogen and oxygen | Look at the Figure below of water (H 2 O) and hydrogen peroxide (H 2 O 2 ), and read about these two compounds. Both compounds consist of hydrogen and oxygen, but they have different ratios of the two elements. As a result, water and hydrogen peroxide are different compounds with different properties. If you’ve ever used hydrogen peroxide to disinfect a cut, then you know that it is very different from water!. |
Name the virus that causes cold sores. | AIDS | Epstein-Barr | eboli | herpes virus | Metju12. Cold sores are caused by a herpes virus . Public Domain. |
Cardiac veins parallel the small cardiac arteries and generally drain into what sinus? | heart | Veins | lungs | coronary | CHAPTER REVIEW 19.1 Heart Anatomy The heart resides within the pericardial sac and is located in the mediastinal space within the thoracic cavity. The pericardial sac consists of two fused layers: an outer fibrous capsule and an inner parietal pericardium lined with a serous membrane. Between the pericardial sac and the heart is the pericardial cavity, which is filled with lubricating serous fluid. The walls of the heart are composed of an outer epicardium, a thick myocardium, and an inner lining layer of endocardium. The human heart consists of a pair of atria, which receive blood and pump it into a pair of ventricles, which pump blood into the vessels. The right atrium receives systemic blood relatively low in oxygen and pumps it into the right ventricle, which pumps it into the pulmonary circuit. Exchange of oxygen and carbon dioxide occurs in the lungs, and blood high in oxygen returns to the left atrium, which pumps blood into the left ventricle, which in turn pumps blood into the aorta and the remainder of the systemic circuit. The septa are the partitions that separate the chambers of the heart. They include the interatrial septum, the interventricular septum, and the atrioventricular septum. Two of these openings are guarded by the atrioventricular valves, the right tricuspid valve and the left mitral valve, which prevent the backflow of blood. Each is attached to chordae tendineae that extend to the papillary muscles, which are extensions of the myocardium, to prevent the valves from being blown back into the atria. The pulmonary valve is located at the base of the pulmonary trunk, and the left semilunar valve is located at the base of the aorta. The right and left coronary arteries are the first to branch off the aorta and arise from two of the three sinuses located near the base of the aorta and are generally located in the sulci. Cardiac veins parallel the small cardiac arteries and generally drain into the coronary sinus. |
What is a dip slip fault where the dip of the fault plane is vertical? | incline slip | strike - theory | reverse slip | strike-slip | A strike-slip fault is a dip-slip fault where the dip of the fault plane is vertical. Strike-slip faults result from shear stresses. If you stand with one foot on each side of a strike-slip fault, one side will be moving toward you while the other side moves away from you. If your right foot moves toward you, the fault is known as a right-lateral strike-slip fault. If your left foot moves toward you, the fault is a left-lateral strike-slip fault ( Figure below ). |
The major entrance and exit for the respiratory system is which facial orifice? | mouth | pore | ear | nose | The Nose and its Adjacent Structures The major entrance and exit for the respiratory system is through the nose. When discussing the nose, it is helpful to divide it into two major sections: the external nose, and the nasal cavity or internal nose. The external nose consists of the surface and skeletal structures that result in the outward appearance of the nose and contribute to its numerous functions (Figure 22.3). The root is the region of the nose located between the eyebrows. The bridge is the part of the nose that connects the root to the rest of the nose. The dorsum nasi is the length of the nose. The apex is the tip of the nose. On either side of the apex, the nostrils are formed by the alae (singular = ala). An ala is a cartilaginous structure that forms the lateral side of each naris (plural = nares), or nostril opening. The philtrum is the concave surface that connects the apex of the nose to the upper lip. |
Sexual reproduction is the combination of (usually haploid) reproductive cells from two individuals to form a third (usually diploid) unique offspring. sexual reproduction produces offspring with novel combinations of what? | phenotypes | features | cells | genes | Sexual Reproduction Sexual reproduction is the combination of (usually haploid) reproductive cells from two individuals to form a third (usually diploid) unique offspring. Sexual reproduction produces offspring with novel combinations of genes. This can be an adaptive advantage in unstable or unpredictable environments. As humans, we are used to thinking of animals as having two separate sexes—male and female—determined at conception. However, in the animal kingdom, there are many variations on this theme. Hermaphroditism Hermaphroditism occurs in animals where one individual has both male and female reproductive parts. Invertebrates such as earthworms, slugs, tapeworms and snails, shown in Figure 43.5, are often hermaphroditic. Hermaphrodites may selffertilize or may mate with another of their species, fertilizing each other and both producing offspring. Self fertilization is common in animals that have limited mobility or are not motile, such as barnacles and clams. |
What kind of reproduction involves just one parent and produces offspring genetically identical to each other and to the parent? | microscopic reproduction | sexual reproduction | organic reproduction | asexual reproduction | Asexual reproduction is simpler than sexual reproduction. It involves just one parent. The offspring are genetically identical to each other and to the parent. All prokaryotes and some eukaryotes reproduce this way. There are several different methods of asexual reproduction. They include binary fission, fragmentation, and budding. |
What do you call the hard case that surrounds the soft parts of some animals? | membrane | muscles | shell | exoskeleton | |
Choosing to not smoke and using sunscreen are examples of lifestyle choices that help prevent forms of what disease? | viral disease | pnemonia | bacterial disease | cancer | Making healthy lifestyle choices can help prevent some types of cancer. For example, you can reduce your risk of lung cancer by not smoking. You can reduce your risk of skin cancer by using sunscreen (see Figure below ). |
What is said about the speed of rotation in systems that create tornadoes? | it is fast | it is magnetic | it is unchanged | it is slow | There are several other examples of objects that increase their rate of spin because something reduced their moment of inertia. Tornadoes are one example. Storm systems that create tornadoes are slowly rotating. When the radius of rotation narrows, even in a local region, angular velocity increases, sometimes to the furious level of a tornado. Earth is another example. Our planet was born from a huge cloud of gas and dust, the rotation of which came from turbulence in an even larger cloud. Gravitational forces caused the cloud to contract, and the rotation rate increased as a result. (See Figure 10.24. |
In gas exchange, oxygen flows into the blood, and what flows out? | liquid dioxide | naturally dioxide | carbon monoxide | carbon dioxide | Gas exchange is the movement of oxygen into the blood and carbon dioxide out of the blood. |
What happens during the process of digestion? | regurgitation | excretion of food | cell division | breakdown of food | The digestive system consists of organs that break down food, absorb nutrients, and eliminate waste. The breakdown of food occurs in the process of digestion. |
What do you call the folded layers of rock where geologists look for oil? | crests | oscillations | synclines | anticlines | Geologists look for oil in folded layers of rock called anticlines. Oil moves through permeable rock and is trapped by the impermeable cap rock. |
Cutting forests and clearing land has also increased the amount of what in the atmosphere? | pesticides | oxygen | smog | carbon dioxide | Because of human activities, there is more carbon dioxide in the atmosphere today than in the past hundreds of thousands of years. Burning fossil fuels and has released great quantities of carbon dioxide into the atmosphere. Cutting forests and clearing land has also increased carbon dioxide into the atmosphere because these activities reduce the number of autotrophic organisms that use up carbon dioxide in photosynthesis. In addition, clearing often involves burning, which releases carbon dioxide that was previously stored in autotrophs. |
Microevolution occurs in a population when what frequencies change over time? | antenna | eukaryote | molecule | allele | Microevolution occurs in a population when its allele frequencies change over time. There are four major forces of evolution that cause allele frequencies to change: mutation, gene flow, genetic drift, and natural selection. |
What is the alkaline hydrolysis reaction of an ester called? | resorption | instantiation | fermentation | saponification | Saponification describes the alkaline hydrolysis reaction of an ester. The term saponification originally described the hydrolysis of long-chain esters called fatty acid esters to produce soap molecules, which are the salts of fatty acids. One such soap molecule is sodium stearate, formed from the hydrolysis of ethyl stearate. |
What is the time interval required for one complete wave to pass a point called? | half-life | cycle | minute | period | The time interval required for one complete wave to pass a point is called the period . During the period of the wave, an entire wavelength from one crest to the next crest passes a position. The number of waves that pass a single position in one second is called the frequency . The period of a wave and its frequency are reciprocals of each other. |
Plant-like protists are autotrophs, meaning they make their own what? | molds | spores | flowers | food | Plant-like protists are autotrophs, meaning they make their own food. |
In what form do plants and animals store sugar for later use? | carrying polysaccharides | processing polysaccharides | management polysaccharides | storage polysaccharides | |
What forces the fetus out of the uterus? | deep breathing | biological clock | delayed childbirth | continuous strong contractions | |
The large and small intestine are both divided into how many parts? | 2 | 6 | 8 | 3 | From the small intestine, any remaining food wastes pass into the large intestine. The large intestine is a relatively wide tube that connects the small intestine with the anus. Like the small intestine, the large intestine also consists of three parts: the cecum (or caecum), colon, and rectum. Follow food as it moves through the digestive system at http://www. youtube. com/watch?v=Uzl6M1YlU3w (1:37). |
If everything in a system stays the same but the pressure deceases, gas bubbles will change in what way? | they get smaller | they multiply | they pop | they get bigger | Gas bubbles get bigger when they are under less pressure. |
What do you call the transfer of thermal energy? | precipitation | formation | humidity | heat | Thermal energy is the total energy of moving particles of matter. The transfer of thermal energy is called heat. Therefore, a heating system is a system for the transfer of thermal energy. Regardless of the type of heating system in a home, the basic function is the same: to produce thermal energy and transfer it to air throughout the house. |
The outer layer of what anatomical structure is so tough that it keeps out most pathogens? | bark | liver | steel | skin | This drawing shows that the skin has many layers. The outer layer is so tough that it keeps out most pathogens. |
The process of a liquid becoming a gas is called boiling, while the process of a solid becoming a gas is called what? | Melting | vaporization | Boiling | sublimation | Temperature does not change during a phase change. The process of a liquid becoming a gas is called boiling; the process of a solid becoming a gas is called sublimation. |
How does the nucleus divide during nuclear fission? | equally | evenly | biochemically | asymmetrically | Collision of a relatively slow-moving neutron with a fissile nucleus can split it into two smaller nuclei with the same or different masses. Neutrons are also released in the process, along with a great deal of energy. Any isotope that can undergo a nuclear fission reaction when bombarded with neutrons is called a fissile isotope. During nuclear fission, the nucleus usually divides asymmetrically rather than into two equal parts, as shown in Figure 20.7 "Neutron-Induced Nuclear Fission". Moreover, every fission event of a given nuclide does not give the same products; more than 50 different fission modes have been identified for uranium235, for example. Consequently, nuclear fission of a fissile nuclide can never be described by a single equation. Instead, as shown in Figure 20.8 "Mass Distribution of Nuclear Fission Products of ", a distribution of many pairs of fission products with different yields is obtained, but the mass ratio of each pair of fission products produced by a single fission event is always roughly 3:2. Figure 20.8 Mass Distribution of Nuclear Fission Products of 235U. |
How do heavy alkanes affect the skin? | color the skin | they do not affect the skin | damage the skin | form a protective layer | Lighter alkanes wash away protective skin oils; heavier alkanes form a protective layer. |
If an electric current passes through water, water molecules break down into molecules of what? | oxygen and methane | carbon and oxygen | hydrogen and carbon | hydrogen and oxygen | The arrow in Figure above shows that the reaction goes from left to right, from hydrogen and oxygen to water. The reaction can also go in the reverse direction. If an electric current passes through water, water molecules break down into molecules of hydrogen and oxygen. This reaction would be represented by a right-to-left arrow in Figure above . |
What makes luminous dials glow in the dark? | eerie substances | polymer substances | devil substances | phosphorescent substances | Once excited, an atom or molecule will usually spontaneously de-excite quickly. (The electrons raised to higher levels are attracted to lower ones by the positive charge of the nucleus. ) Spontaneous de-excitation has a very short mean lifetime of −8 typically about 10 s . However, some levels have significantly longer lifetimes, ranging up to milliseconds to minutes or even hours. These energy levels are inhibited and are slow in de-exciting because their quantum numbers differ greatly from those of available lower levels. Although these level lifetimes are short in human terms, they are many orders of magnitude longer than is typical and, thus, are said to be metastable, meaning relatively stable. Phosphorescence is the de-excitation of a metastable state. Glow-in-the-dark materials, such as luminous dials on some watches and clocks and on children’s toys and pajamas, are made of phosphorescent substances. Visible light excites the atoms or molecules to metastable states that decay slowly, releasing the stored excitation energy partially as visible light. In some ceramics, atomic excitation energy can be frozen in after the ceramic has cooled from its firing. It is very slowly released, but the ceramic can be induced to phosphoresce by heating—a process called “thermoluminescence. ” Since the release is slow, thermoluminescence can be used to date antiquities. The less light emitted, the older the ceramic. (See Figure 30.35. |
What liquid is referred to as the "universal solvent"? | blood | bromine | gasoline | water | Not only salt, but many other solutes can dissolve in water. In fact, so many solutes can dissolve in water that water has been called the universal solvent. Even rocks can dissolve in water, which explains the cave that opened this article. A solute that can dissolve in a given solvent, such as water, is said to be soluble in that solvent. Conversely, a solute that cannot dissolve in a given solvent is said to be insoluble in that solvent. |
What is the active ingredient in cloves? | thiamine | nicotine | methyl | eugenol | Eugenol, the active ingredient in cloves, has the formula C 10 H 12 O 2 . Eugenol is a molecular substance that does not dissociate into ions when dissolved in a solvent. What is the boiling point of a solution in which 0.144 g of eugenol is dissolved in 10.0 g benzene? The k b value for benzene is 2.53 °C/ m , and the boiling point of pure benzene is 80.1 °C. |
What term means the adjusting of systems within a cell in order to restore balance or maintain equilibrium? | gaseous regulation | systemic regulation | aftertouch regulation | homeostatic regulation | Homeostasis refers to the balance, or equilibrium, within the cell or a body. It is an organism’s ability to keep a constant internal environment. Keeping a stable internal environment requires constant adjustments as conditions change inside and outside the cell. The adjusting of systems within a cell is referred to as homeostatic regulation. Because the internal and external environments of a cell are constantly changing, adjustments must be made continuously to stay at or near the normal proportions of all internal substances. This involves continual adjustments in transport of substances across the cell membrane. Homeostasis is a dynamic equilibrium rather than an unchanging state. The cellular processes discussed in the cell transport (passive and active transport) concepts all play an important role in homeostatic regulation. |
What is the name of the formation that regulates sleep and arousal? | sleep-arousal formation | gelechioidea formation | epithelial formation | reticular formation | |
What do the gonadotropins regulate? | mitosis | temperature | epigenesis | gametogenesis |
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