Biology Quiz 1

Question 1

What does DNA’s structure explain?

Answer 1

The stability of life, how genetic info is stored, how genetic info is passed on, and the mutability of life.

Question 2

What is Photo 51 taken by Rosalind Franklin?

Answer 2

It was the first picture of DNA, taken in 1951. It showed that DNA was a doubel helix that was 4 units wide.

Question 3

Where is genetic information stored?

Answer 3

In the sequence of the bases.

Question 4

What are the bases of DNA?

Answer 4

Adenine, cytosine, guanine, and thymine

Question 5

What are the base pairing rules of DNA?

Answer 5

AT, GC

Question 6

What is a DNA nucleotide?

Answer 6

It’s the molecule that makes up DNA.
It consists of a phosphate group, deoxyribose (a type of sugar), and a nitrogenous base.

Question 7

What is a DNA backbone?

Answer 7

It’s a strand of DNA made by the connection of phospate in different nucleotides.

Question 8

What bond is used to join DNA bases?

Answer 8

A hydrogen bond

Question 9

What are the differences between DNA and RNA?

Answer 9

DNA (deoxyribonucleic acid) and RNA (ribonucleic acid) are different because:

1. DNA is made of deoxyribose, while RNA is made of ribose
2. Instead of having the base thymine, RNA has the base uracil
3. RNA is single stranded, unlink DNA

Question 10

What is protein?

Answer 10

Proteins are complex molecules made of amino acids that perform specific functions.

Question 11

Explain how DNA is converted into protein.

Answer 11

1. DNA makes a copy of itself called “coding DNA”
2. The coding DNA is then copied to mRNA in a process called TRANSCRIPTION
3. The mRNA leaves the cell’s nucleus to go to the ribosome
4. The mRNA is read by tRNA in sections of 3 called “codons”
5. The mRNA is converted to amino acids by tRNA in a process called TRANSLATION
6. All the amino acids eventually join together in a link called a polypeptide chain, which eventually becomes a protein

Question 12

What are the 3 types of RNA?

Answer 12

mRNA (messenger RNA, takes genetic information from the nucleus to the ribosome)
tRNA (converts mRNA into protein)
rRNA (is what makes up a ribosome)

Question 13

What is a ribosome?

Answer 13

It’s the cell’s organelle that converts mRNA into protein.

Question 14

Where is DNA found in a cell?

Answer 14

The nucleus

Question 15

What is DNA replication?

Answer 15

It’s when DNA makes a copy of itself.

Question 16

What are the molecules involved in DNA replication?

Answer 16

Helicase: splits the double helix in half
Primase: coats the existing DNA strands, telling the POLYMERASE where to build
Polymerase: builds new DNA
Ligase: closes the gaps between Okazaki fragments on the lagging strand

Question 17

What is the difference between leading and lagging strands in DNA replication?

Answer 17

Leading strand: since polymerase can only build in a set direction, the LEADING strand simultaneously builds in the same direction that the helicase is unzipping the DNA in

Lagging strand: since polymerase builds in the opposite direction, it can only build in short bursts called “Okazaki fragments”. This leaves short, empty spaces where the polymerase didn’t build. The ligase “glues together” these empty spaces.

Question 18

What does semi-conservative mean?

Answer 18

In DNA replication, it means that each new strand is made up of one original strand and one new strand.

Question 19

How do you use a microscope?

Answer 19

1. Position and fasten the slide under the microscope
2. Start on low power
3. Use the coarse adjustment knob (big knob) to change the elevation of the stage
4. Repeat these steps when you transition from low to medium to high power
5. when you’re in high power, use the fine adjustment knob (little knob)

Question 20

What was the role of everything in the DNA extraction lab?

Answer 20

Detergent: breaks the cell membrane and nucleus to get the DNA out
Enzyme (meat tenderizer): unwinds the proteins that DNA is built around
Alcohol: decreases the solubility of the dissolved DNA, makes it form into clumps