EXAM 4

1. List the following steps of the scientific method in the correct order: 1) Analyze results 2) Form a hypothesis 3) Make a prediction 4) Ask a question 5) Make an observation 6) Perform a test or experiment ______ ______ ______ ______ ______ ______

5,4,2,3,6,1

1. Disease-causing bacteria in a human begin to multiply rapidly when they sense that their numbers are high enough to overpower an immune response. This is possible because of A. quorum sensing B. plasmids C. horizontal gene transfer D. sporulation

A.

1. In _______________, pairs of homologous chromosomes do not separate normally during meiosis I or sister chromatids fail to separate during meiosis II. As a result, one gamete receives two of the same type of chromosome, and another gamete receives no copy. A. Nondisjunction B. Tight junction C. Gap junction D. Cell junction

A.

1. Normal cells use checkpoints to control speed of cell division and prevent cell division with damaged or incomplete DNA. A. True B. False

A.

The enzyme amylase can break glycosidic linkages between glucose monomers only if the monomers are in the α form. Which of the following could amylase break down? A. Glycogen, starch, and amylopectin B. Glycogen and cellulose C. Cellulose and chitin D. Starch, chitin, and cellulose

A.

1. The smallest level of biological organization that can carry out all activities needed for life (i.e., the smallest unit of life) is A. Organelles B. Cells C. Molecules D. Organisms E. Populations

B

1. If you are not getting enough vitamins in your food, what are you missing? A. allosteric regulators B. cofactors C. Metal ions D. minerals

B.

1. In photosynthesis, the carbon used to make sugars is A. provided by enzymes. B. provided by carbon dioxide. C. extracted from DNA. D. oxidized to make sugars.

B.

1. Mendel deciphered the five principles of inheritance with full knowledge and understanding of chromosomes or DNA. A. True B. False

B.

1. Organisms pass on their traits from one generation to the next through inheritance of DNA molecules. This illustrates which theme of life? A. Order B. Information C. Energy D. Interactions E. Evolution

B.

1. Some antibiotics used to treat bacterial infections kill the bacteria by chemically punching holes in the cell wall of the bacteria, by preventing the bacteria from replicating their DNA, or by many other actions that ultimately cause cell death. Why do these antibiotics not work to kill viruses and cure people of viral infections? A. Viruses are too virulent to be killed by those antibiotics. B. Antibiotics cannot kill a virus because viruses are not living cells with cell walls to puncture, nor do they have the structures necessary for autonomous reproduction. C. Viruses mutate at a rate faster than the rate at which antibiotics can kill them. D. Viruses are too quick for the antibiotics to work.

B.

1. The pH of healthy human blood is in the range of ______________. A. 6.80 - 7.00 B. 7.35 - 7.45 C. 7.60 - 7.80 D. 8.00 - 8.20

B.

1. Which of the following is NOT an application of recombinant DNA technology? A. Genetically modified corn for herbicide resistance B. DNA fingerprinting in forensic science C. Bacteria modified to clean oil spills D. Bacteria culture used to produce hormones for treating diabetes and dwarfism

B.

1. Why are X-linked recessive genetic disorders more commonly seen in males? A. For an X-linked disorder to occur, an individual must receive one allele found only on the X chromosome and a second allele found only on the Y chromosome, which females do not have. B. Females must receive two copies of the recessive allele to exhibit the disorder, but males need only one copy. C. The alleles of sex-linked genes are carried only on the Y chromosome, which females do not have. D. Females only have X chromosomes and genes on the X chromosome are not expressed.

B.

1. A common chemotherapy drug is Taxol, which stabilizes microtubules so they cannot shrink. What stage of mitosis does this arrest (freeze) cells in? A. Prophase, because the DNA cannot condense B. Metaphase, because the spindle fibers cannot elongate to push the chromosomes to the equator C. Anaphase, because the spindle fibers cannot pull the sister chromatids apart D. Cytokinesis, because cleavage furrows cannot form

C.

1. A scientific theory is A. A logical prediction based on careful observations of the natural world B. A fact discovered through scientific experimentation by a group of scientists C. A general principle or idea about the natural world supported by a large body of research evidence (data) over time D. An idea shared by some scientists, but highly contested by other scientist

C.

1. Adenine (A), thymine (T), guanine (G), and cytosine (C) are the __________ building blocks for DNA; they are organized in different combinations to code for all the proteins needed to accomplish everything the cell does. A. lipid B. protein C. nucleotide D. carbohydrate

C.

1. Carbon dioxide is one product of a metabolic process, which occurs in both plants and animals. This process is called A. Catalysis B. Glycolysis C. Cellular respiration D. Photosynthesis

C.

1. Down Syndrome is caused by the presence of a third copy of chromosome 21. Having three copies instead of two homologous chromosomes is called what? A. Triplet code error B. Tricot C. Trisomy D. Incomplete dominance

C.

1. Each time a person takes a breath, they are bringing in the oxygen needed to stay alive. The ultimate source of the oxygen used by all aerobic organisms comes from a reaction that breaks down A. Carbon dioxide B. ATP C. Water NADPH

C.

1. If a recessive allele causes a fatal disease that kills the affected individual before he or she can reproduce, why doesn't that allele quickly become extinct in the population? A. Alleles are never lost from a population. B. The homozygous dominant individuals protect the recessive allele in their genomes. C. The recessive allele is carried in the genome of heterozygotes, who do not suffer from the disease. D. The homozygous recessive individuals give their alleles to other individuals before they die from the disease.

C.

1. In genetic engineering, molecular biologists often combine segments of DNA from two separate organisms. This is an example of genetic recombination that occurs in a laboratory setting. Which of the following is a form of genetic recombination that occurs naturally within cells? A. Mitosis B. Independent assortment C. Crossing-over D. Asexual reproduction

C.

1. Patients with sickle cell anemia have a short life expectancy, and rarely produce offspring to pass on their trait. In some regions of the world, however, where malaria is prevalent, being heterozygous for sickle cell anemia is protective against malaria, and therefore natural selection has caused an increase in the frequency of the mutated sickle cell allele. This is called A. Genetic drift B. Incomplete dominance C. Heterozygote advantage D. An environment-influenced trait

C.

1. Viruses generally are NOT considered living things. Which of the following characteristic of life DOES describe viruses? A. Made of cells B. Use energy C. Can mutate and evolve (change) D. Independently express and transmit their genes to offspring

C.

1. _______________ is a technique for correcting abnormal genes responsible for disease development. A. Chemotherapy B. Immunotherapy C. Gene therapy D. Divine therapy

C.

Which chemical group is an important component of the ATP molecule? A. Hydroxyl group B. Carbonyl group C. Phosphate group D. Methyl group E. Amino group

C.

1. A polysaccharide you are studying contains unbranched β glucose molecules and cannot be digested by humans. Which polysaccharide are you studying? A. Carbohydrates B. Starch C. Glycogen D. Cellulose

D.

1. In autumn, chlorophyll is degraded in the leaves of deciduous trees. Why do the leaves change color to shades of yellow, orange, or red? A. Sugars from sap fill the leaves prior to winter. B. Degraded chlorophyll changes into many other colors. C. In the absence of photosynthesis, the leaves produce energy exclusively by aerobic cellular respiration. D. Other pigments such as carotenoids are still present in the leaves as green chlorophyll disappears

D.

1. Most ________ diseases (such as heart disease, cancer, stroke, and diabetes) are caused by multiple genes interacting in complex ways with each other and with external factors. They are ___________ traits: malfunctions in key genes make a person susceptible to developing these diseases, but environmental factors and lifestyle choices affect whether the disease will actually appear and how severe the symptoms will be. A. Acute; monogenic B. Acute; polygenic C. Chronic; monogenic D. Chronic; complex

D.

1. The sequence of DNA differs among individuals within a species. This is the reason for A. mutation. B. protein structure. C. base-pairing. D. variations in phenotypes.

D.

1. Water shows high cohesion and surface tension and can absorb large amounts of heat because of large numbers of which of the following bonds between water molecules? A. Strong ionic bonds B. Nonpolar covalent bonds C. Polar covalent bonds D. Hydrogen bonds E. Weak ionic bonds

D.

1. What is the importance of photosynthesis to organisms other than plants? A. All other organisms require carbon dioxide for life processes. B. The sugars made during photosynthesis are the direct building blocks of DNA. C. All cells must contain chloroplasts in order to survive. D. Photosynthesis captures energy that other organisms access when they ingest or absorb nutrients from photosynthetic organisms.

D.

1. Which of the following scientists was NOT involved in the discovery of the DNA molecule and its chemical structure? A. Rosalind Franklin B. James Watson and Francis Crick C. Erwin Chargaff D. Gregor Mendel

D.

1. Which two processes combine to create genetic diversity and maintain chromosome number? A. Mitosis and meiosis B. Meiosis and independent assortment C. Binary fission and mitosis D. Fertilization and meiosis

D.

Which of the following molecules has a hydrophilic head and a hydrophobic tail, enabling these molecules to self-assemble in water, forming a double-layered structure or "bilayer"? Hint: They are the "fabric" of cell membranes. A. Fatty acids B. Steroids C. Polypeptides D. Phospholipids E. Nucleic acids

D.

1. ABO blood type in humans exhibits codominance and multiple alleles. What is the likelihood of a type AB father and a type A mother having a type O child? Hint: The father is heterozygous, IAIB, and the mother is heterozygous, IAIO. Refer to the figure below. Draw a Punnett square to guide you. A. 10% B. 25% C. 50% D. 70% E. It is impossible.

E.