BIO 181 TEST

If a gene is 3000 molecules long how many amino acids will the polypeptide chain have?

999

Which is bigger, the gene or chromosome?

Chromosome

What enzyme catalyzes the elongation of a DNA strand in the 5' to 3' direction?

DNA Polymerase III

What is the enzyme that makes DNA called?

DNA polymerase

Why do histones bind tightly to DNA?

Histones are positively charged and DNA is negatively charged

3 steps of transcription

Initiation, elongation, termination

What is the role of DNA ligase in the elongation of the lagging strand during DNA replication?

It joins okazaki fragments together

From your understanding of the cell structure, when the newly made polypeptide is to be secreted from the cell where it has been made, what must occur?

Its signal sequence must lead it to the ER, from which it goes to the Golgi

What is the enzyme that makes RNA called?

RNA polymerase

An enzyme called__ catalyzes the lengthening of telomeres in eukaryotic germ cells.

Telomerase

What is a ribozyme?

an RNA with enzymatic activity

For every protein you need a _____

gene

What is a gene?

info for amino acid sequence

______are non coding segments of mRNA, and ______ are segments that code for functional products

introns, exons

In transcription, what is initiation?

it allows attachment, initiation factor proteins

What amino acid sequence will be generated, based on the following mRNA codon sequence? 5' AUG-UCU-UCG-UUA-UCC-UUG 3'

met-ser-ser-leu-ser-leu

What is the function of topolsomerase?

relieving strain in the DNA ahead of the replication fork

In transcription, what is termination?

reverse transcript, makes double strand

In transcription, what is elongnation?

seperate

Carries an amino acid to a strand of mRNA

tRNA

The leading and the lagging strands differ in that_____

the leading strand is synthesized in the same direction as the movement of the replication fork and the lagging strand is synthesized in the opposite direction