AP Biology Unit 6 Review

1.

Multiple Choice

1 min

1 pt

When does DNA replication take place?

Whenever new genes are needed

During the S phase of the cell cycle

In the middle of mitosis or meiosis

Immediately before cytokinesis begins

Answer explanation

The DNA must be replicated before cell division takes place so that the daughter cells each receive all the necessary information

Tags

IST-1

2.

Match

1 min

1 pt

Match the following enzymes to their roles in DNA replication.

Unwinds the parent DNA strands

Ligase

Adds a small RNA "primer"

Primase

Fills in the gaps in the new DNA strands

Helicase

Synthesizes the new strands of DNA

DNA polymerase

Tags

IST-1

3.

Multiple Choice

1 min

1 pt

DNA replication involves many different enzymes. Helicase unwinds the DNA so that the parent strands can be seperated. DNA polymerase adds the nucleotides to synthesize the daughter strands. What is the role of primase?

It adds a small RNA "primer" to allow DNA polymerase to begin

It sorts the prime numbers of RNA into even piles

It removes incorrecly matched nucleotides to avoid mutations

It connects the gaps between nucleotide segments

Tags

IST-1

4.

Labelling

1 min

1 pt

Label the stages of protein synthesis.

mRNA processing

Translation

Transcription

Gene regulation

Tags

IST-1

5.

Multiple Choice

1 min

1 pt

Which of the following would lead to an increase in the rate of transcription?

methylation of DNA, particularly the cytosine bases

acetylation of histone proteins

binding of the operator in an operon

negative feedback from accumulating product

Tags

IST-2

6.

Multiple Select

1 min

1 pt

Which of the following are part of a bacterial lac operon? (Select all that apply)

Promotor

Genes for lac enzymes

Regulatory genes

Enhancers

Tags

IST-2

7.

Match

2 mins

1 pt

Match the following genetic regions to their roles:

Operator

The on/off switch where the repressor protein binds

Regulatory gene

Codes for the main protein / enzymes

Genes of Operon

Place where transcription begins

Promotor

Makes a repressor protein

Tags

IST-2

8.

Multiple Choice

1 min

1 pt

The trp operon in E. Coli is responsible for making 5 polypeptides involved in the tryptophan synthesis pathway. When tryptophan is present, it combines with the repressor protein to block the operator. What type of operon is trp?

Repressible

Inducible

Tags

IST-2

9.

Drag and Drop

1 min

1 pt

The operon model was discovered in E. Coli and is almost exclusively found in (a) .

prokaryotes

eukaryotes

Tags

IST-2

10.

Multiple Choice

1 min

1 pt

After eukaryotic transcription takes place, mRNA undergoes several modifications before leaving the nucleus to take part in translation. Some sections of mRNA are cut out, and the remaining sections are spliced together to create the finished mRNA molecule. Which of the following mRNA sections are spliced together in the finished mRNA molecule?

introns

exons

operons

ribozymes

Tags

IST-2

11.

Multiple Choice

1 min

1 pt

The human genome appears to have only about as many genes as the simple nematode worm, C. elegans. Which of the following best explains how the more complex humans can have relatively few genes?

Human genes have unusually long introns involved in the regulation of gene expression

More than one polypeptide can be produced from a gene by alternative gene splicing

The human genome has a high proportion of noncoding DNA

The human genome has a large number of SNPs (single nucleotide polymorphisms) which increases genetic variability

Tags

IST-2

12.

Reorder

2 mins

1 pt

Reorder the following stages of protein synthesis in eukaryotes:

Activators bind to the enhancer

A DNA bending protein folds the enhancer toward the promotor

RNA polymerase transcribes the DNA beginning at the promotor

Introns are removed from the mRNA; a poly-A tail is added

mRNA leaves the nucleus to find a ribosome for translation

Tags

IST-2

13.

Multiple Choice

1 min

1 pt

What type of molecule helps turn on specific genes?

Inducers

Repressors

Methalation

Morphogenesis

Tags

IST-2

14.

Match

1 min

1 pt

Match the following processes to their associated phrase.

A mobile segment of DNA that can travel from one location on a chromosome to another.

Transcription

The synthesis of polypeptides from the genetic information coded in mRNA

Transposon

The synthesis of mRNA from a DNA template.

DNA methylation

The addition of chemical groups to certain bases of DNA which regulates gene expression.

Translation

Tags

IST-2

15.

Multiple Choice

1 min

1 pt

The human globin genes are located on two different chromosomes and include variants that are expressed at different times in the life cycle as well as several nonfunctional pseudogenes. Which of the following would best describe this gene family?

All the functional genes in the family have the same transcription control elements

This gene family would be equivalent to the operons of prokaryotes

Mutations in the hemoglobin gene led to its translocation to two different chromosomes

Identical or similar genes have evolved by gene duplication

Answer explanation

This is an example of a multigene family. The alpha-globin gene family is on chromosome 16, whereas the bata-globin gene family is on chromosome 11. The genes arose by duplication and translocation.

Tags

IST-2

Explore this activity with a free account