Question

1) A small piece of DNA or RNA, which is usually radioactive, and that is used to locate one’s gene of interest in a cloned DNA library, is known as a… A) Primer B) Bacteriphage C) Polymerase D) Vector E) Probe
2) Screening a library means… A) Keeping the window screens closed in the learning resource center to prevent insects from eating the       books B) Inserting cloned DNA into plasmids C) Finding the cloned gene of interest D) Inserting plasmids into bacteria E) Digesting the genomic DNA with restriction enzymes
3) In the genomic DNA isolation lab, the purpose of sodium chloride is to... A) Keep the nucleus intact for the first steps of the procedure B) Destroy DNA molecules that might contaminate the RNA C) Separate proteins from DNA D) Precipitate the DNA
4) A carbon atom is most likely to form what kind of bond(s) with hydrogen atoms? A) non-polar covalent B) hydrogen C) polar covalent D) ionic

5) The diffuse spread out state of chromosomes is known as... A) Nucleic acid B) Nucleus C) Chromatin D) Centriole E) Nucleiod matter
6) A certain object weighs 2.8 x 103 grams. In normal numbers, this weight is... A) 0.0028 grams B) 2800 grams C) 280 grams D) 2.8 grams
7) The symbol for diploid is… A) XX B) -- C) || D) XY E) 2n
8) Heterozygous is defined as... A) An organism that has gained one of extra chromosomes B) An organism with two of each chromosome type (two chromosome 1's, two chromosome 2's, etc). C) A cell with two identical nuclei D) An organism with two different alleles for a gene E) A cell that contains more than one chromosome

9) Cinnabar eyes is a sex-linked recessive characteristic in fruit flies. If a female having cinnabar eyes is crossed with a normal (red eye) male, what percentage of the F1 males will have cinnabar eyes? A) 25% B) 50% C) 75% D) 100%
10) Black fur in mice (B) is dominant to brown fur (b). Long tails (T) are dominant to short tails (t). What fraction of the offspring of crosses BbTt × BBtt will be expected to have black fur and long tails? A) 1/2 B) 3/16 C) 3/8 D) 1/16 E) 9/16
11) Which number is closest to the total number of genes in the human genome? A) 25,000 B) 46 C) 10,000 D) 100,000
12) The Alu sequence is not capable of moving or copying itself in the genome. How then is Alu moved and copied? A) By unequal crossing over in meiosis. B) By imitating an intron and being duplicated by RNA polymerase II. C) Using the reverse transcriptase enzyme of active retrotransposons. D) By imitating an exon and being duplicated by RNA polymerase II. E) It encodes enzymes that are able to copy and splice itself within the genome.

13) Which of the following statements is correct about diffusion? A) It is very rapid over long distances. B) It requires an expenditure of energy by the cell. C) It is an active process in which molecules move from a region of lower concentration to one of higher concentration. D) It is a passive process in which molecules move from a region of higher concentration to a region of lower concentration.
14) Which of the following is characterized by a cell releasing a signal molecule which diffuses into the local environment, followed by nearby cells responding? A) hormonal signaling B) autocrine signaling C) synaptic signaling D) endocrine signaling E) paracrine signaling
15) An enzyme that adds a phosphate functional group to amino acids is called a… A) kinase B) ATPase C) cyclase D) amino phosphotase E) ATP synthase
16) When a G protein-linked receptor binds signal molecule, the first relay protein to be activated is… A) G-protein B) phospholipase C. C) adenylyl cyclase. D) tyrosine kinase. E) serine/threonine kinase.

17) During aerobic respiration, H2O is formed. Where does the oxygen atom for the formation of the water come from? A) carbon dioxide (CO2) B) glucose (C6H12O6) C) pyruvate (C3H3O3-) D) molecular oxygen (O2)
18) The molecule NADH (nicotinamide adenine dinucleotide) is used by cells to carry… A) carbon atoms B) electrons C) ribose D) nicotine E) glucose
19) How many carbon dioxide molecules (CO2) are produced for each molecule of glucose (C6H12O6) is completely oxidized to carbon dioxide and water via aerobic respiration? A) 4 B) 6 C) 32 D) 36
20) High levels of Citric acid inhibit the enzyme phosphofructokinase, a key enzyme in glycolysis. Citric acid binds to the enzyme at a different location from the active site. This is an example of A) competitive inhibition. B) positive feedback regulation. C) the specificity of enzymes for their substrates. D) an enzyme requiring a cofactor. E) allosteric regulation.

Answer 1

1) The correct answer is option E i.e. probe.

2) The correct answer is option C i.e. finding the cloned gene of interest.

3) The correct answer is option C i.e. separate proteins from DNA.

4) The correct answer is option A i.e. non-polar covalent bond.

5) The correct answer is option C i.e. chromatin.

6) The correct answer is option B i.e. 2800 grams.

7) The correct answer is option i.e. 2n.

8) The correct answer is option D i.e. An organism with two different alleles for a gene.

9) The correct answer is option B i.e. 50%.

Let Xc is allele for cinnabar eyes and X is normal allele for eyes (wild type). Cinnabar eyes is a X-linked recessive and is common in males. So, when the female for cinnabar eyes (XcXc) is crossed with normal male (XY), the possible genotypes are:

XcX = female carrier

XcY = affected male

XcX = female carrier

XcY = affected male

Thus, the proportion of F1 having cinnabar eyes is 2/4x100 = 50%>

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10) The correct answer is option A i.e. 1/2. This is because, BbTt has 4 gametes: BT, Bt, bT, and bt whereas BBtt has 1 gamete i.e. Bt. When these are crossed, the possible genotypes are:

BT x Bt = BBTt = Black and long

Bt x Bt = BBtt = Black and short

bT x Bt = BbTt = Black and long

bt x Bt = Bbtt = Black and short

Thus, only 2 out of 4 genotypes have Black and long fur. So, the probability is 2/4 = 1/2.

11) The correct answer is option A i.e. 25000.

12) The correct answer is option C i.e. Using the reverse transcriptase enzyme of active retrotransposons.

13) The correct answer is option D i.e. It is a passive process in which molecules move from a region of higher concentration to a region of lower concentration.

14) The correct answer is option E i.e. paracrine signalling.

15) The correct answer is option A i.e. kinase.

16) The correct answer is option A i.e. G protein.

17) The correct answer is option D i.e. molecular oxygen (O2).

18) The correct answer is option B i.e electrons.

19) The correct answer is option B i.e. 6.

20) The correct answer is option E i.e. allosteric regulation.