Bio Test 3 Practice Questions

Why do histones bind tightly to DNA? A) Histones are positively charged, and DNA is negatively charged. B) Histones are negatively charged, and DNA is positively charged. C) Both histones and DNA are strongly hydrophobic. D) Histones are covalently linked to the DNA. E) Histones are highly hydrophobic, and DNA is hydrophilic.

A

In meiosis I (in humans) how many pairs of homologous chromosomes line up at the metaphase plate? (A)46 (B)23 (C)92 (D)None of these

B

The Rec8 protein holds sister chromatids together during meiosis. If an individual has a mutation that prevents degradation of Rec8, this would most likely prevent A. normal segregation during meiosis I. B. normal segregation during meiosis II. C. synapsis of homologous chromosomes. D. crossing over during prophase

B

The point of constriction on chromosomes that contains certain repeated DNA sequences that bind specific proteins is called: A. The centriole B. The centromere C. The kinetochore D. The centrosome E. The cohesin complex

B

Which cell cycle checkpoint monitors the integrity of the DNA replication? (A) G1/S (B) G2/M (C) Spindle (D) G1/M (E) G2/S

B

DNA replication occurs... A) only before mitosis. B) only before meiosis. C) before both mitosis and meiosis I. D) before mitosis, meiosis I, and meiosis

C

In mitosis, _____ chromosomes line up at metaphase and in meiosis II, ______ chromosomes line up at metaphase. (A)46, 46 (B)23, 23 (C)46, 23 (D)23, 46 (E)92, 46

C

The bonds between nucleotide base pairs are _______________ bonds while the bonds between nucleotides on the sugar-phosphate backbone of DNA are _______________ bonds. (A)Covalent, hydrogen (B)Hydrogen, ionic (C)Hydrogen, phosphodiester (D)Phosphodiester, hydrogen (E)Ionic, phosphodiester

C

What is the function of DNA polymerase III? A) to unwind the DNA helix during replication B) to seal together the broken ends of DNA strands C) to add nucleotides to the 3' end of a growing DNA strand D) to degrade damaged DNA molecules E) to rejoin the two DNA strands (one new and one old) after replication

C

At a specific area of a chromosome, the following sequence of nucleotides is present where the chain opens to form a replication fork: 3'-C C T A G G C T G C A A T C C-5' An RNA primer is formed starting at the underlined T (T) of the template. Which of the following represents the primer sequence? A) 5'-G C C T A G G-3' B) 3'-G C C T A G G-5' C) 5'-A C G T T A G G-3' D) 5'-A C G U U A G G-3' E) 5'-G C C U A G G-3'

D

DNA consists of two antiparallel strands of nucleotides held together by A. peptide bonds. B. covalent bonds. C. ionic bonds. D. hydrogen bonds

D

If a cell was capable of bypassing metaphase and going directly from prometaphase to anaphase, what is the most likely consequence of this? A. The resulting daughter cells would be completely normal. B. The resulting daughter cells would have significantly different quantities of cytoplasmic materials. C. The resulting daughter cells would not have a nuclear envelope. D. The resulting daughter cells would have different numbers of chromosomes.

D

Suppose a new form of DNA polymerase III is discovered that does not require a primer to begin synthesis of a new strand. All other properties of the enzyme remain unchanged. If this new enzyme were to be expressed in the same organism that normally expresses DNA polymerase III, what would no longer be necessary to completely replicate all of the cellular DNA? A. DNA polymerase I B. Primase C. DNA ligase D. More than one of these E. All of these

D (A and B)

DNA primase.... A. creates a short RNA primer that is complementary to an RNA template. B. creates a short DNA primer that is complementary to an RNA template. C. creates a short DNA primer that is complementary to a DNA template. D. creates a short DNA template that is complementary to an RNA primer. E. creates a short RNA primer that is complementary to a DNA template

E

If we unwound all the DNA in just one of your cells and lined it up, double helix to double helix, how long would that dsDNA be? A.Less than an inch B.1-6 inches C.6-12 inches D.3 feet E.6 feet

E

Ok, so we have six ft of DNA in every cell! If we unwound all the DNA in your body and lined it up, double helix to double helix, how long would that dsDNA be? A.The distance of Milwaukee to Chicago B.All the way across America C.It could wrap around the equator D.That piece of DNA would stretch to the moon and back! E. 65X around the earth and sun!

E

What kinds of bonds is DNA polymerase making as it carries out DNA replication? (A)Hydrogen (B)Covalent (C)Phosphodiester (D)Ionic (E)More than one of these is correct

E

When we say the chromosomes are condensing, does that have anything to do with histones?

Yes