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Stack #1135231
Science MidTerm Review
Question | Answer |
---|---|
A hypothesis is | a proposed explanation for a set of observations |
The role of a control in an experiment is to | provide a basis of comparison to the experimental group |
If you eat a hamburger, you are mainly eating ground-up beef muscle. What levels of organization are represented in this ground-up muscle? | organelle, cell, and tissue |
An example of a stimulus that a plant would respond to is: | sunlight. |
Which of the following things would be considered complex AND organized? | red blood cell in the human body |
DNA is a molecule that directly allows a living thing to: | store information. |
The process of homeostasis is: | how organisms maintain a relatively constant internal environment. |
Living systems need energy to: | grow larger, replace worn-out parts and build new parts, help maintain a relatively constant internal environment. |
The complexity of living systems: | is also highly organized. |
Identify a characteristic that is representative of some, but not all, life-forms. | movement over great distances |
Which function below is performed by eukaryotic cells, but not prokaryotic cells? | internal digestion of cellular garbage by a structure called a lysosome |
Biology is the study of _____. | life |
Which series of terms is in the sequence of biological organization from the simplest to the most complex? | cell, tissue, organ, population |
Compared to a solution of pH 3, a solution of pH 1 is | 100 times more acidic. |
Household ammonia has a pH of 12; household bleach has a pH of 13. Which of the following statements about them is true? | The ammonia has 10 times as many H+ ions as the bleach. |
Which four elements are the primary components of important biological molecules, such as proteins, fats, and carbohydrates? | nitrogen, carbon, hydrogen, and oxygen |
An atom and an ion of the same element differ in the number of _____. | electrons |
The hydrogen bonds in liquid water are less stable than in ice. Why? | There is less movement of molecules in colder conditions. |
To understand biology, we need to understand chemistry. Why? | Chemicals are fundamental to the structure and function of all living things. |
The pH of human blood is maintained at around pH 7.4. Why does a buffer system need to be present in blood to protect against changes in pH due to increases in acids? | The metabolic processes of the body produce more acids than bases. |
The number of protons in an uncharged atom _____. | equals the total number of electrons in the orbital shells |
Two atoms of the same element must have the same number of _____. | protons |
Which of the following subatomic particles shown below always has a positive charge? | proton |
Which of the following describes a covalent bond? | Two or more atoms share electron pairs. |
An ionic bond in which a sodium atom transfers an electron to a chlorine atom, making sodium ion and a chlorine ion. This is a result of what? | an attraction between atoms that have opposite charges |
A hydrogen bond is _____. | weak |
What is the tendency of water molecules to stick together is called what? | Cohesion |
Water can resist temperature change because _____. | heating water absorbs energy by disrupting the hydrogen bonds before evaporation can occur |
Cells are surrounded by water, and cells themselves are about 70-95% water. As a result, _____. | a variety of nutrient molecules are readily available as dissolved solutes |
What property of water makes it move upward from the roots of plants? | cohesion |
What is an acid? An acid _____. | donates hydrogen ions to solutions |
A solution with a pH of 7 is | neutral. |
Organic compounds | always contain carbon. |
A hydroxyl group is | characteristic of alcohols. |
Which of the following is a carboxyl group? | ―COOH |
Which of the following is an amino group? | ―NH2 |
Which of the following statements about the monomers and polymers found in living organisms is false? | Monomers are joined together by the process of hydrolysis. |
What is the general function of enzymes within a cell? | to speed up chemical reactions |
The storage form of carbohydrates is ________ in animals and ________ in plants. | glycogen . . . starch |
Fatty acids are | hydrophobic. |
Proteins differ from one another because | the sequence of amino acids in the polypeptide chain differs from protein to protein. |
Which of the following statements about enzymes is false? | They are monomers used to build proteins. |
The cells that produce hair contain a lot of ________, while the cells that produce the oils that coat the hair contain a lot of ________. | rough endoplasmic reticulum . . . smooth endoplasmic reticulum |
A woman is having trouble becoming pregnant. Examination of her partner's sperm indicates that dynein feet are missing from the flagella in his sperm cells. A physician explains that this could interfere with fertility by | preventing the sperm from swimming to the egg cell. |
Which of the following statements about cells is true? | All cells have internal structures that move. |
The idea that all living things are composed of cells and that all cells come from other cells defines | cell theory. |
Plasma membranes are permeable to | nonpolar molecules such as CO2. |
Which of the following structures is exclusively associated with prokaryotic cells? | nucleoid |
Unlike animal cells, plant cells have ________ and ________. Unlike plant cells, animal cells have ________. | chloroplasts . . . cell walls . . . centrioles |
The nucleus of a cell | contains DNA. |
During cell reproduction, chromatin fibers coil up into structures called | chromosomes. |
Which location in the cell is unlikely to contain ribosomes or ribosomal subunits? | plasma membrane |
The endomembrane system includes all of the following organelles except the | peroxisome. |
Smooth endoplasmic reticulum | stores calcium ions in muscle cells. |
The Golgi apparatus | stores, modifies, and packages proteins. |
The function of mitochondria is | cellular respiration. |
The function of chloroplasts is | photosynthesis. |
The stroma is the | thick fluid enclosed by the inner chloroplast membrane. |
Mitochondria differ from chloroplasts in that mitochondria | contain membrane folds called cristae, whereas chloroplasts contain disk-like vesicles in stacks called grana. |
Microfilaments differ from microtubules in that microfilaments | are mainly composed of actin, whereas microtubules are composed of tubulin. |
Which of the following statements about the cytoskeleton is false? | Once laid down, the elements of the cytoskeleton are fixed and remain permanently in place. |
Cilia differ from flagella in that | cilia are typically more numerous and shorter than flagella. |
Most animal cells are | embedded in an extracellular matrix. |
Which of the following substances would have the most trouble crossing a biological membrane by diffusing through the lipid bilayer? | Na+ |
Which of the following statements is true among all types of passive transport? | The concentration gradient is the driving force. |
A hypotonic cell | explodes |
The fluid mosaic model describes the plasma membrane as consisting of | diverse proteins embedded in a phospholipid bilayer. |
Most of the functions of a cell membrane, including transport and enzymatic function, are performed by | proteins. |
Plasma membranes are selectively permeable. This means that | the plasma membrane allows some substances to enter or leave a cell more easily than others. |
Oxygen crosses a plasma membrane by | passive transport. |
Diffusion does not require the cell to expend ATP. Therefore, diffusion is considered a type of | passive transport. |
Osmosis can be defined as | the diffusion of water. |
A cell that neither gains nor loses water when it is immersed in a solution must be | isotonic to its environment. |
Which of the following processes can move a solute against its concentration gradient? | active transport |
Phagocytosis is to eating as pinocytosis is to | drinking. |
The active site of an enzyme is | the region of an enzyme that attaches to a substrate. |
Which of the following statements regarding enzymes is true? | Enzymes catalyze specific reactions. |
Respiration ________, and cellular respiration ________. | is gas exchange . . . produces ATP |
The processes of photosynthesis and cellular respiration are complementary. During these energy conversions, some energy is | lost in the form of heat. |
Which of the following statements regarding photosynthesis and cellular respiration is true? | Photosynthesis occurs in chloroplasts, and cellular respiration occurs in mitochondria. |
Which of the following are products of cellular respiration? | energy to make ATP and carbon dioxide |
The overall equation for the cellular respiration of glucose is | C6H12O6 + 6 O2 → 6 CO2 + 6 H2O + energy. |
The functioning of an electron transport chain is analogous to | a Slinky toy going down a flight of stairs. |
Which of the following metabolic pathways is common in aerobic and anaerobic metabolism? | glycolysis |
As a result of glycolysis there is a net gain of ________ ATPs. | 2 |
After glycolysis but before the citric acid cycle, | pyruvate is oxidized. |
Which of the following processes produces the most ATP per molecule of glucose oxidized? | aerobic respiration |
Mitochondria transfer ________ energy from ________ to ATP; chloroplasts transform ________ energy into the chemical energy of ATP. | chemical . . . food . . . light |
Plant cells | have mitochondria and chloroplasts. |
The thylakoid membrane is | the membrane that surrounds the stack of "cookies" |
What is the name given to organisms that can make their own food and thus sustain themselves without consuming organic molecules derived from other organisms? | autotrophs |
What is the source of energy that provides the boost for electrons during photosynthesis? | light |
Which of the following statements regarding photosynthesis is false? | ATP is not produced during photosynthesis, but only during cellular respiration. |
The light reactions occur in the ________, while the Calvin cycle occurs in the ________. | thylakoid membranes . . . stroma |
Why are most plants green? | Chlorophyll a reflects green light. |
Which of the following features likely accounts for the difference between plant and animal cell cytokinesis? | Plant cells have cell walls. |
A plant cell in telophase | Has a cell wall and have 2 distinct cells forming |
Which of the following statements regarding cell division is false? | Cell division is common in eukaryotes but rare in prokaryotes. |
Sister chromatids are | joined together at a centromere. |
Which of the following occurs during interphase? | cell growth and duplication of the chromosomes |
Eukaryotic cells spend most of their cell cycle in which phase? | interphase |
The genetic material is duplicated during | the S phase. |
The process by which the cytoplasm of a eukaryotic cell divides to produce two cells is called | cytokinesis. |
The phase of mitosis during which the mitotic spindle begins to form is | prophase. |
During which phase of mitosis do the chromosomes line up on a plane equidistant from the two spindle poles? | metaphase |
At the start of mitotic anaphase, | the centromeres of each chromosome come apart. |
During which phase of mitosis does the nuclear envelope re-form? | telophase |
Which of the following statements regarding the function of mitosis is false? | Mitosis allows organisms to generate genetic diversity. |
Which of the following statements regarding mitosis and meiosis is false? | Mitosis produces daughter cells with half the number of chromosomes as the parent cell. |
Of the following wavelengths of light, which would you expect to be reflected or transmitted by chlorophyll a? | green |
Which of the following are produced during the Calvin cycle? | glucose, ADP, NADP+ |
Which of the following is part of the light reaction? | formation of waste products in the form of O2 |
Which of the following are produced during the light reactions of photosynthesis? | ATP, NADPH, O2 |