BIO 121 Quiz 1

Select all the bases which qualify as Pyrimidines

Cytosine Thymine Uracil

Which of the following is INACCURATE and NOT a reason why DNA is present in all living things on earth?

DNA is more polar than RNA

Okazaki fragments are combined by which of the following enzymes?

DNA ligase

Which of the following enzymes is directly responsible for synthesizing a new DNA strand in a 5'-3' direction? (Which catalyzes the addition of new nucleotides?)

DNA polymerase

What is the basis for the difference in how the leading and lagging strands of DNA molecules are synthesized?

DNA polymerase can join new nucleotides only to the 3' end of a pre-existing strand, and the strands are antiparallel.

Which of the following is unique to the lagging strand in DNA synthesis?

Okazaki fragments

The structure of biological macromolecules consists mostly of ___________ atoms linked together by __________ bonds.

carbon, covalent

Life as we know it is based on the ability to...

replicate DNA

Which of the following are features that all cells have (choose all correct responses)?

-DNA -Cytosol -Plasma Membrane -Ribosome

Watson and Crick, who discovered the double helical structure of DNA, wrote that this structure revealed the possible mechanisms for replication. Why was this so? (Choose all correct responses)

-The structure of a molecule corresponds to its function, so learning what a molecule looks like can provide insight into what the molecule does. -Each strand of the double helix contained all the information necessary to make the other strand.

Which of the following are properties of water that account for its ability to sustain life on Earth? (choose all correct responses)

-Water molecules stick to one another through electrostatic interactions called hydrogen bonds. -Water expands upon freezing allowing life to thrive in water even in frigid environments. -Water dissolves biological macromolecules such as nucleic acids, proteins, and carbohydrates.

Which of the following are common to all nucleotides?

-phosphate group -5 carbon sugar -nitrongenous base

Which of the following are properties that should be true for all living things; both on this planet and elsewhere in the universe? (Select all that apply)

-self replication -maintain internal order

Thymine makes up 28% of the nucleotides in a sample of (double stranded) DNA from an organism - Approximately what percentage of the nucleotides in this sample will be guanine?

22%

In an analysis of nucleotide composition of a molecule of DNA, which of the following combinations of base pairs will be found?

A+C= G+T

In analyzing the number of different bases in a DNA sample, which result would be consistent with the base-pairing rules?

A+G=T+C

DNA is considered a self-replicating molecule because...

All of the information necessary to replicate the DNA is contained within the DNA molecule itself.

G1

Cell growth

Which would be the most convincing evidence of life on other planets?

Discovery of a molecule on another planet that is capable of self-replication

G2

Final preparation phase. Cell checks for DNA errors and begins to form centrosomes. (Prepares for Mitosis)

Which of the following is true regarding DNA polymerase?

It builds a DNA polymer that is complementary to the template strand

A nucleotide consists of a central ribose sugar, which connects on the 5' end to a phosphate group and on the 1' carbon to a

Nitrogenous base

In E. coli, there is a mutation in a gene called dnaB that alters the helicase that normally acts at the origin. Which of the following would you expect as a result of this mutation?

No replication fork will be formed.

Anaphase

Phase of mitosis in which the chromosomes separate and move to opposite ends of the cell

A nucleotide consists of a central ribose sugar , which connects on the 5' end to a

Phosphate group

A nucleotide consists of a central

Ribose Sugar

prometaphase

The second stage of mitosis, in which the nuclear envelope fragments and the spindle microtubules attach to the kinetochores of the chromosomes.

When nucleotides polymerize to form a nucleic acid _____.

a covalent bond forms between the sugar of one nucleotide and the phosphate of a second

A cell that lacks membrane-bound organelles and that has a circular chromosome is which of the following?

a prokaryotic cell

Astrobiologists search outer space for signs of life referred to as...

biosignitures

cytokinesis

division of the cytoplasm

prophase

dna condenses, centrosomes replicate (poles created)

Please match the macromolecule type with its monomer. ("e.g." provides an example of that molecule) Lipids

fatty acid

Which enzyme or protein is necessary for unwinding the DNA and forming the replication fork?

helicase

If life exists on other planets, it must...

none

Which of the following typically describes two Carbon atoms sharing electrons, such as those found within a nitrogenous base?

non polar covalent bond

Please match the macromolecule type with its monomer. ("e.g." provides an example of that molecule) Nucleic Acid

nucleotide

Which of the following statements best describes the molecule shown below?

nucleotide

Which monomers make up RNA?

nucleotides

metaphase

phase of mitosis in which the chromosomes line up across the center of the cell

telophase

phase of mitosis in which the distinct individual chromosomes begin to spread out into a tangle of chromatin -dna recondenses, nuclear envelope forms

What mechanism best describes the replication of DNA?

semi-conservative

Please match the macromolecule type with its monomer. ("e.g." provides an example of that molecule) Carbohydrate

sugar

Why do chromosomes condense during mitosis?

to allow the chromosomes to move without becoming entangled and breaking

Which of the following best describes DNA?

two complementary nucleic acid polymers, running in opposite directions, interacting through hydrogen bonds

Which of the following is a major difference between RNA and DNA?

type of sugar

Match each sequence to its complement 5'-ATGGCAT-3'

5'-ATGCCAT-3'

Match each sequence to its complement 5'-CGTAAGG-3'

5'-CCTTACG-5'

Match each sequence to its complement 3'-GAATTCG-5'

5'-CTTAAGC-3'

Match each sequence to its complement 5'-GGAATGC-3'

5'-GCATTCC-3'

S phase

The synthesis phase of the cell cycle; the portion of interphase during which DNA is replicated.

Select all the bases which qualify as Purines.

adenine and guanine

Please match the macromolecule type with its monomer. ("e.g." provides an example of that molecule) Protein

amino acid

Which of the following is(are) broken when water evaporates?

hydrogen bonds