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Rio Bio 156 Exam 1, 2, Midterm and Final Exam
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Exam 1
Distinguish between a producer, a consumer and a decomposer. ----------- Correct Answer --------
- producer:photosynthetic organisms that trap light and convert that light energy into chemical bond energy. such as some bacteria, protists, and all plants consumer: organisms that feed on already-stored food decomposer: bacteria and fungi recycle the dead molecules throughout the bioshpere. Distinguish between a hypothesis and a prediction. ----------- Correct Answer --------- hypothesis: testable explanation of a natural phenomenon. prediction: statement based on hypothesis about a condition that should exit if the hypothesis is correct. What is meant by the phrase potentially falsifiable hypothesis? ----------- Correct Answer --------- a hypothesis can be proven that is false Define the term control group and explain the value of a control group in an experiment. ----------
- Correct Answer --------- Group of individuals identical to an experimental group except for the independent variable under investigation To provide a basis of comparison to the experimental group Define the term theory and explain the point in which a hypothesis becomes a theory. ----------- Correct Answer --------- Suppose a hypothesis stands even after years of tests. It is consistent with all data ever gathered, and it has helped us make successful predictions about other phenomena. Explain how electron configuration influences the chemical properties of an atom. ----------- Correct Answer --------- Each cloud can hold a determinant number of electrons. When the electron number changes, ions are formed. The number of electrons influences the bonding between atoms. hydrogen bond ----------- Correct Answer --------- The electron from the hydrogen spends most of its time around the oxygen atom creating a partial positive charge on each hydrogen. The presence of additional electrons makes the oxygen partially negative. covalent bond ----------- Correct Answer --------- two atoms share a pair of electrons, so that each atom's vacancy
becomes partially filled ionic bond ----------- Correct Answer --------- Type of chemical bond in which a strong mutual attraction links ions of opposite charge. Describe how water contributes to the fitness of the environment that supports all life. ----------- Correct Answer --------- 1. an excellent solvent
- has cohesion (insect on water, water roots)
- stabilize temperature (cool surface) Explain the basis for the pH scale. ----------- Correct Answer --------- The basis for the pH scale is the amount of H+ and OH- ions in a solution. More H+ ions means a solution is more acidic, while more OH- ions means the solution is more basic. List features that distinguish living organisms from nonliving matter. ----------- Correct Answer - -------- 1. Cellular basis - All living things consist of one or more cells
- Requirement for energy and nutrients - Life is sustained by ongoing inputs of energy and nutrients
- Homeostasis - Living things sense and respond to change
- DNA is hereditary material - Genetic information in the form of DNA is passed to offspring Describe the levels of organization in the living world. ----------- Correct Answer --------- Atoms → cells → tissues → organs → organ systems → organism → population → community → ecosystem → the biosphere List the three domains of life and distinguish between each domain. ----------- Correct Answer --- ------ Prokaryotes are bacteria and archaea. Domain Bacteria: unicellular no nucleus Domain Archaea: unicellular no nucleus but closer to eukarya Domain Eukarya: have nucleus List four kingdoms within the domain Eukarya and distinguish between them. ----------- Correct Answer --------- 1. Fungi can be single or multicellular but digest food outside their body.
- Plants are multicellular and are photosynthetic.
- Animals are multicellular and eat other organisms for nutrients.
- Protists are the unicellular organisms that have a nucleus but do not fit any other category. List and describe the steps involved in solving a problem using hypothesis-based science --------- -- Correct Answer --------- observation hypothesis experimental conclusion Describe the concept "an organism is more than the sum of its parts." ----------- Correct Answer - -------- organism is part of a more complex organization. These emergent properties go beyond itself.
Describe the molecular structure and importance of DNA. ----------- Correct Answer --------- A DNA molecule consists of two chains of nucleotides twisted into a double helix. Each cell starts life with DNA inherited from a parent cell. Identify a peptide bond and explain how it is formed. ----------- Correct Answer --------- covalent bond that links amino acids in a protein During protein synthesis, a peptide bond forms between the carboxyl group of the first amino acid and the amine group of the second Define the primary, secondary (two forms), tertiary, and quaternary structure of a protein. -------- --- Correct Answer --------- 1. primary structure is order of the amino acids
- secondary structure has alpha helix and the beta pleated sheet. tertiary structure interactions between the r- groups of amino acids.
- quaternary structure is the interaction between multiple polypeptide chains.
- making up membrane structure, antibodies, enzymes, neurotoxins, and hair and nail structure. also used as an energy source. List the major components of a nucleotide ----------- Correct Answer --------- monomers of nucleic acids. contains sugar, nitrogen base, and one ore more phosphate groups. Cite the key features of the Cell Theory. ----------- Correct Answer --------- 1. Every living organism consists of one or more cells.
- The cell is the structural and functional unit of all organisms. A cell is the smallest unit of life, individually alive even as part of a multicelled organism.
- All living cells arise by division of preexisting cells.
- Cells contain hereditary material, which they pass to their offspring when they divide. Compare and contrast the structure and function of mitochondria and chloroplasts. ----------- Correct Answer --------- mitochondria: Makes ATP by glucose breakdown chloroplast: Makes sugars (in plants, some protists) List several surface structures of cells and explain how they help cells survive. ----------- Correct Answer --------- Cell Wall: Protects, structurally supports cell Plasma membrane: selectively permeable and controls exchanges between the cell and its environment. Describe the major kinds of microscopes and explain their main use. ----------- Correct Answer -- ------- Light microscope uses light to pass through the image onto magnifying lenses. Scanning electron microscope scans the outside of cell surfaces. Transmission electron microscope can magnify the internal cellular structures. Describe how the relationship between the surface area of a cell and its volume changes as the cell increases in size. ----------- Correct Answer --------- A cell's surface area increases with the square of its diameter, while its volume increases with the cube. This surface- to-volume ratio
limits cell size and influences cell shape. Explain two reasons why smaller cells are biologically more efficient than larger cells. ----------- Correct Answer --------- The rate of exchange across a plasma membrane depends on its surface area: The bigger it is, the more substances can cross it during a given interval. Describe the eukaryotic nucleus ----------- Correct Answer --------- Keeps DNA separated from cytoplasm; makes ribosome subunits; controls access to DNA Identify the unique features of a prokaryotic cell ----------- Correct Answer --------- cytoplasm with ribosome dna plasma membrane cell wall capsule pilus bacterial flagellum Vesicles ----------- Correct Answer --------- membrane-enclosed sacs that often form by budding from other components of the endomembrane system. Many transport substances among organelles of the ER, and to and from the plasma membrane. Other vesicles store or break down substances. Rough ER ----------- Correct Answer --------- Ribosomes attached to the rough ER use RNA in the cytoplasm to make polypeptides. The newly synthesized polypeptide chains enter rough ER, where they take on tertiary structure and assemble with other polypeptide chains. Smooth ER ----------- Correct Answer --------- Proteins migrate through the interior of the rough ER, and end up in the smooth ER. Some stay in smooth ER, as enzymes that assemble lipids and break down carbohydrates, wastes, and toxins. Other proteins are packaged in vesicles for transport to Golgi bodies. Golgi Body ----------- Correct Answer --------- Proteins and lipids arriving in vesicles are modified into final form, sorted, and repackaged into new vesicles. Some of these vesicles ferry proteins to the plasma membrane for secretion or insertion into the lipid bilayer. Others become lysosomes. Describe the function of chloroplasts ----------- Correct Answer --------- Site of photosynthesis Describe the function of mitochondria ----------- Correct Answer --------- Energy powerhouse; produces many ATP by aerobic respiration Describe the function of the cytoskeleton. ----------- Correct Answer --------- Structural support, development, cell division, organelle movement
Passive transport mechanism in which a solute follows its concentration gradient across a membrane by moving through a transport protein. Distinguish between exocytosis and endocytosis. ----------- Correct Answer --------- endocytosis: Process by which a cell takes in a small amount of extracellular fluid (and its contents) by the ballooning inward of the plasma membrane. exocytosis: Process by which a cell expels a vesicle's contents to extracellular fluid. Describe an amoeba feeding by phagocytosis. ----------- Correct Answer --------- a type of receptor-mediated endocytosis in which motile cells engulf microorganisms, cellular debris, or other large particles. Describe the basic events of glycolysis. ----------- Correct Answer --------- a series of reactions beginning with the breakdown of a glucose molecule to pyruvate. A small amount (two molecules) of ATP is produced directly at this time. Electrons are carried to the electron transport chain by NADH, a special coenzyme electron carrier. Glycolysis takes place in the cytoplasm of the cell. Describe the basic events of Krebs Cycle ----------- Correct Answer --------- The Krebs cycle, or Citric Acid Cycle, is the name given to the set of reactions in which pyruvate is broken down by enzymes to carbon dioxide. Again, a small amount of ATP (two molecules) is made directly during these events. Once again, electrons are carried to the electron transport chain by NAD+. Another electron carrier, FAD, is also active here. The Krebs cycle takes place in the matrix of the mitochondria - the area outside of the cristae. aerobic ----------- Correct Answer --------- Involving or occurring in the presence of oxygen. anaerobic ----------- Correct Answer --------- Occurring in the absence of oxygen. aerobic respiration ----------- Correct Answer --------- Oxygen-requiring metabolic pathway that breaks down sugars to produce ATP. aerobic respiration can be dangerous ----------- Correct Answer --------- When an oxygen molecule (O2) accepts electrons from an electron transfer chain, it dissociates into oxygen atoms. Most of the atoms immediately combine with hydrogen ions and end up in water molecules. however, an oxygen atom escapes this final reaction. The atom has an unpaired electron, so it is a free radical. mitochondria cannot detoxify free radicals, so they rely on antioxidant enzymes and vitamins in the cell's cytoplasm to do it for them. oxidative stress ----------- Correct Answer --------- Free radicals accumulate and destroy first the function of mitochondria, then the cell. The resulting tissue damage by mitochondrial malfunction is also involved in many other illnesses, including cancer, hypertension, Alzheimer's and Parkinson's diseases, and even aging. symptoms: mild to major progressive neurological deficits, blindness, deafness, diabetes, strokes, seizures, gastrointestinal malfunction, and disabling muscle weakness.
aerobic respiration three stages ----------- Correct Answer --------- 1. glycolysis
- krebs cycle
- electron transfer phosphorylation Glycolysis ----------- Correct Answer --------- take place in cytoplasm begins breakdown of one sugar molecule for a net yield of 2 ATP. Krebs cycle ----------- Correct Answer --------- take place in mitochondrion completes the breakdown of the sugar molecule to CO2. produces 2 ATP, reduced many coenzymes deliver electrons and hydrogen ions to electron transfer chains. electron transfer phosphorylation ----------- Correct Answer --------- Energy released by electrons as they move through the chains drives the formation of as many as 32 ATP. At the end of the electron transfer chains, water forms when oxygen accepts hydrogen ions and electrons. fermentation ----------- Correct Answer --------- A metabolic pathway that breaks down sugars to produce ATP and does not require oxygen. begins with glycolysis in cytoplasm produce only 2 ATP and an organic molecule accepts electrons. good for anaerobic conditions Pyruvate ----------- Correct Answer --------- Three-carbon end product of glycolysis. substrate-level phosphorylation ----------- Correct Answer --------- The formation of ATP by the direct transfer of a phosphate group from a substrate to ADP. alcoholic fermentation ----------- Correct Answer --------- Anaerobic sugar breakdown pathway that produces ATP, CO2, and ethanol. wine making, bread making lactate fermentation ----------- Correct Answer --------- Anaerobic sugar breakdown pathway that produces ATP and lactate. yogur running Ethanol ----------- Correct Answer --------- move quickly from stomach and small intestine into the bloodstream. ends up in the liver. interferes with normal processes of metabolism ADH (alcohol dehydrogenase) ----------- Correct Answer --------- helps break down ethanol and other toxic compounds.
catalysis ----------- Correct Answer --------- an enzyme makes a reaction run much faster than it would on its own. substrates ----------- Correct Answer --------- Of an enzyme, a reactant that is specifically acted upon by the enzyme. transition state ----------- Correct Answer --------- Point during a reaction at which substrate bonds will break and the reaction will run spontaneously to completion. induced-fit model ----------- Correct Answer --------- Substrate binding to an active site improves the fit between the two. active site ----------- Correct Answer --------- Pocket in an enzyme where substrates bind and a chemical reaction occurs. allosteric regulation ----------- Correct Answer --------- Control of enzyme activity by a regulatory molecule or ion that binds to a region outside the enzyme's active site. electron transfer chain ----------- Correct Answer --------- Array of membrane-bound enzymes and other molecules that accept and give up electrons in sequence, thus releasing the energy of the electrons in steps. feedback inhibition ----------- Correct Answer --------- Regulatory mechanism in which a change that results from some activity decreases or stops the activity. metabolic pathway ----------- Correct Answer --------- Series of enzyme-mediated reactions by which cells build, remodel, or break down an organic molecule. redox reaction ----------- Correct Answer --------- Oxidation-reduction reaction; typically, one mol- ecule accepts electrons (it becomes reduced) from another molecule (which becomes oxidized). antioxidant ----------- Correct Answer --------- Substance that prevents oxidation of other molecules. ATP/ADP cycle ----------- Correct Answer --------- Process by which cells regenerate ATP. ADP forms when ATP loses a phosphate group, then ATP forms again as ADP gains a phosphate group. coenzyme ----------- Correct Answer --------- An organic cofactor. cofactor ----------- Correct Answer --------- A coenzyme or metal ion that associates with an enzyme and is necessary for its function. phosphorylation ----------- Correct Answer --------- A phosphate-group transfer.
Exam 2
Interphase is the stage when __________. ----------- Correct Answer ----------- a cell grows and duplicates its DNA. In an individual with a dominant phenotype is crossed with an individual with a recessive phenotype, 4 of their 9 offspring show the recessive phenotype. What is the genotype of the first parent? ----------- Correct Answer ----------- Bb Solve this monohybrid genetics problem: Black hair is governed by the dominant gene (B) and blond hair is determined by the recessive gene (b). In this monohybrid cross, if both parents are heterozygous, what percentage of the offspring would be expected to have blond hair? ----------- Correct Answer ----------- 25% A Punnett square can be used to determine___________. ----------- Correct Answer ----------- the genotype of an offspring Different alleles of the same gene are found ----------- Correct Answer ----------- at the same place on homologous chromosomes If a parental cell has 14 chromosomes prior to mitosis, how many chromosomes will each daughter cell have? ----------- Correct Answer ----------- 14 because the chromatids separate a duplicated chromosome has _____ chromatid(s) ----------- Correct Answer ----------- 2 Mendel was fortunate to work out the laws of segregation and independent assortment because he used an organism that reproduced quickly and in which the traits were discrete (easy to observe). Mendel's organism of choice was the ----------- Correct Answer ----------- pea plant What is the importance of crossing-over? ----------- Correct Answer ----------- It increases the likelihood that daughter cells contain different genetic material. Assuming that the probability of having a female child is 50% and the probability of having a male child is also 50%, what is the probability that a couple's firstborn child is female and second-born child is male? ----------- Correct Answer ----------- 25 % If a parental cell has 12 chromosomes, then each of the daughter cells following meiosis will have _____. ----------- Correct Answer ----------- 6 chromosomes. Which of the following genotypes would be homozygous dominant for both alleles? ----------- Correct Answer ----------- DDEE Which sequence of stages in mitosis is correct? ----------- Correct Answer ----------- prophase, prometaphase, metaphase, anaphase, telophase
Crossing-over occurs between _____. ----------- Correct Answer ----------- nonsister chromatids of chromosomes. In a Mendelian monohybrid cross, which generation is always completely heterozygous? --------- -- Correct Answer ----------- F1 generation Which of the following is FALSE? ----------- Correct Answer ----------- Most human genetic diseases are treatable if caught early. What is the normal complement of sex chromosomes in a human male? ----------- Correct Answer ----------- one X chromosome and one Y chromosome Which refers to the loss of a portion of a chromosome? ----------- Correct Answer ----------- deletion Nondisjunction occurs when ----------- Correct Answer ----------- members of a chromosome pair fail to separate. Which of the following terms refers to the situation where a single phenotypic characteristic is determined by the additive effects of two or more genes? ----------- Correct Answer ----------- polygenic inheritance. Which disease results in deformed red blood cells, poor circulation, and anemia? ----------- Correct Answer ----------- sickle-cell disease Linked genes generally ----------- Correct Answer ----------- do not follow the laws of independent assortment. When you trace the occurrence of a specific characteristic through your past ancestry, you are constructing a family ______________. ----------- Correct Answer ----------- pedigree Which refers to the movement of a piece of one chromosome to another nonhomologous chromosome? ----------- Correct Answer ----------- translocation Imagine that beak color in a finch species is controlled by a single gene. You mate a finch homozygous for orange (pigmented) beak with a finch homozygous for ivory (unpigmented) beak and get numerous offspring, all of which have a pale, ivory-orange beak. This pattern of color expression is most likely to be an example of ----------- Correct Answer ----------- incomplete dominance Recessive X-linked traits are more likely to be expressed in a male than a female because --------- -- Correct Answer ----------- the male's phenotype results entirely from his single X-linked gene. An abnormal number of chromosomes could result during meiosis because of ____. ----------- Correct Answer ----------- nondisjunction
What causes Down syndrome? ----------- Correct Answer ----------- an extra chromosome 21 Solve the following multiple allele problem: Susan, a mother with Type B blood, has a child with Type O blood. She claims that Craig, who has Type A blood, is the father. He claims that he cannot possibly be the father. Further blood tests ordered by the judge reveal that Craig is AA. The judge rules that ----------- Correct Answer ----------- Craig is right and doesn't have to pay child support Sometimes, linked genes are not inherited because they are broken apart during the formation of the gametes. These breaks are caused by ----------- Correct Answer ----------- crossing over The expression of both alleles for a trait in a heterozygous individual illustrates ----------- Correct Answer ----------- co-dominance A karyotype is most like which of the following? ----------- Correct Answer ----------- Photographs of every couple at a high school prom By studying a karyotype, a prospective parent would be able to tell ----------- Correct Answer ---- ------- if there is an alteration in the number of chromosomes. A person who has type AB blood illustrates the principle of ----------- Correct Answer ----------- co-dominance In a pedigree chart, which is correct? ----------- Correct Answer ----------- A line between a circle and a square represents a mating. How many sex chromosomes are in an egg or a sperm? ----------- Correct Answer ----------- one A carrier of a genetic disorder who does not show symptoms is most likely to be __________ to transmit it to offspring. ----------- Correct Answer ----------- heterozygous for the trait and able Human skin color varies greatly from one individual to another. The specific genetic situation to account for this fact is ----------- Correct Answer ----------- polygenic inheritance - several genes act together to govern the phenotype of a certain characteristic. If a colorblind woman marries a colorblind man, the chances of any daughter being of normal vision is ----------- Correct Answer ----------- 0% A man has hemophilia, but his parents do not. Using H for normal and h for hemophilia, give the genotype of his father, mother, and himself in that order. ----------- Correct Answer ----------- XHY, XHXh, XhY In the gene arrangement ABCDEFG breaks and a segment repositions itself so that the segment now reads ABEDCFG, what specific kind of mutation has occurred? ----------- Correct Answer -- --------- Inversion
If the DNA triplets were ATG-CGT, the mRNA codons would be _____________. ----------- Correct Answer ----------- UAC-GCA Gel electrophoresis separates DNA molecules on the basis of ----------- Correct Answer ----------- their lengths. When a virus takes over the machinery of a cell, it forces the cell to manufacture ----------- Correct Answer ----------- more viral particles. When one DNA molecule is copied to make two DNA Molecules, each new DNA molecule contains: ----------- Correct Answer ----------- 50% of the parent DNA. Retroviruses such as HIV use __________ to convert information stored in their RNA to information stored in DNA. ----------- Correct Answer ----------- reverse transcriptase If one sticky end has the nucleotide sequence TTAA exposed, the piece of DNA that will come in and attach to that sticky end will have the sequence ___________. ----------- Correct Answer -- --------- AATT In the gel electrophoresis chamber, the DNA fragments migrate toward the __________ charged pole. ----------- Correct Answer ----------- positively Which of the following is the enzyme that HIV uses to synthesize DNA on an RNA template? --- -------- Correct Answer ----------- reverse transcriptase The transfer of genetic information from DNA to RNA is called ----------- Correct Answer ------- ---- transcription. The copying mechanism of DNA is most like ----------- Correct Answer ----------- using a photographic negative to make a positive image. The monomers of DNA and RNA are ----------- Correct Answer ----------- nucleotides. A physical or chemical agent that changes the nucleotide sequence of DNA is called ----------- Correct Answer ----------- a mutagen. The one gene-one polypeptide theory states that ----------- Correct Answer ----------- the function of an individual gene is to dictate the production of a specific polypeptide. Translation consists of which of the following? ----------- Correct Answer ----------- the conversion of genetic information from the language of nucleic acids to the language of proteins If you commit a crime, you need to make sure that you do not leave even the smallest speck of blood, hair, etc., from your body behind, because if you do, the DNA in this material can be amplified by __________, subjected to genetic analysis, and used to identify you as the
perpetrator of the crime. ----------- Correct Answer ----------- PCR In the process of human gene cloning using recombinant plasmids, the bacterial plasmid ----------
- Correct Answer ----------- functions as a vector. Segments of eukaryotic DNA that can move or be copied from one site to another in the genome are called ----------- Correct Answer ----------- transposons. Genetically modifying __________ cells may directly affect future generations. ----------- Correct Answer ----------- germ
Midterm Exam
Life is organized in a hierarchical fashion. Which one of the following sequences illustrates that hierarchy as it increases in complexity? ------------ Correct Answer ----------- molecule → cell → tissue → organ → organ system → organism → population → community → ecosystem The tree in your backyard is home to two cardinals, a colony of ants, a wasp's nest (a colony of wasps), two squirrels, and millions of bacteria. Together, all of these organisms represent --------- --- Correct Answer ----------- a community The ultimate source of energy flowing into nearly all ecosystems is ------------ Correct Answer --- -------- sunlight A consumer eating a producer represents ------------ Correct Answer ----------- a transfer of chemical nutrients and energy The formation of systems typically results in the appearance of novel characteristics called ------- ----- Correct Answer ----------- emergent properties A scientist examining a group of cells under the microscope notices the presence of nuclei within these cells. Chemical tests reveal that each cell is photosynthetic and is surrounded by a wall composed of cellulose. These cells must come from an organism that is a member of the Kingdom ------------ Correct Answer ----------- Plantae Which one of the following statements is not consistent with Darwin's mechanism of natural selection? ------------ Correct Answer ----------- Individual organisms exhibit genetic change during their life spans to better fit their environment A hypothesis is ------------ Correct Answer ----------- a tentative answer to some question. A scientist performs a controlled experiment. This means that ------------ Correct Answer --------- -- two experiments are conducted, one differing from the other by only a single variable.
----- cellulose, starch, and glycogen A diet high in animal products may increase the risk for atherosclerosis. This is because ---------- -- Correct Answer ----------- most animal fats are saturated and some animal products contain trans fats. Sucrose is formed ------------ Correct Answer ----------- from two monosaccharides by dehydration synthesis DNA differs from RNA because DNA ------------ Correct Answer ----------- contains thymine in place of uracil Glucose molecules are to starch as __________ are to proteins. ------------ Correct Answer ------- ---- amino acids Nucleotides ------------ Correct Answer ----------- - contain nitrogenous bases.
- contain sugar molecules.
- contain phosphate groups.
- can be linked together to form nucleic acids Genetic information is encoded in the ------------ Correct Answer ----------- sequence of nucleotides in DNA. Light microscopes ------------ Correct Answer ----------- use light and glass lenses to magnify an image. A scanning electron microscope is used to study __________, whereas a transmission electron microscope is used to study __________. ------------ Correct Answer ----------- cell surfaces... internal cell structures Which of the following statements is consistent with the Cell Theory? ------------ Correct Answer ----------- The cell is the basic structural and functional unity of life. We can characterize the fluid mosaic model of a membrane as ____________ floating in a sea of ___________ ------------ Correct Answer ----------- proteins; lipid Large, round cells can overcome surface area to volume problems by ------------ Correct Answer ----------- becoming smaller, narrower or flatter. As cell size increases, the ------------ Correct Answer ----------- volume increases faster than the surface area. Cells that lack a membrane-bound nucleus are __________ cells. ------------ Correct Answer ----- ------ prokaryotic The membranous compartmentalization of a cell ------------ Correct Answer ----------- allows
different metabolic processes to occur simultaneously. If a biologist said that eukaryotic cells get their power from bacteria, they would be referring to - ----------- Correct Answer ----------- the mitochondria in our cells that may have originated as endosymbiotic bacteria. Long fibers of DNA and protein are called a ------------ Correct Answer ----------- chromatin. Smooth endoplasmic reticulum ------------ Correct Answer ----------- stores calcium ions in muscle cells. Secretory proteins are ------------ Correct Answer ----------- released from the cell through the plasma membrane. The Golgi apparatus ------------ Correct Answer ----------- stores, modifies, and packages proteins. What helps to digest worn-out or damaged organelles, recycle materials within the cell, fuse with food vacuoles to expose nutrients to lysosomal enzymes, destroy harmful bacteria engulfed by white blood cells. ------------ Correct Answer ----------- Lysosomes What prevent cells from bursting as a result of the influx of excess water? ------------ Correct Answer ----------- Contractile vacuoles Cilia differ from flagella in that ------------ Correct Answer ----------- Cilia are typically more numerous and shorter than flagella Plants with rigid cell walls are unable to do which process? ------------ Correct Answer ----------- Phagocytosis Which of the following cell structures is not associated with the breakdown of harmful substances or substances that are no longer needed by the cell? ------------ Correct Answer -------- --- Mitochondria Small, nonpolar, hydrophobic molecules such as fatty acids ------------ Correct Answer ----------- easily pass through a membrane's lipid bilayer. Which one of the following is not a function of membrane proteins? ------------ Correct Answer - ---------- - serve as enzymes.
- attach the membrane to the cytoskeleton.
- provide cellular identification tags.
- form junctions between cells. Diffusion does not require the cell to expend ATP. Therefore, diffusion is considered a type of: -- ---------- Correct Answer ----------- Passive transport
