Unit 1 DNA and Unit 2 Cell Cycle/mitosis

Question 1

steps of DNA replication in order

Answer 1

(a) The double stranded molecule is “unzipped” into two single strands.
(b) the original strand of DNA serves as a template for new nucleotides using the base pair rule.
(c) DNA polymerase “rezips” nucleotides that have attached to the original strand

Question 2

Rosalind Franklin

Answer 2

• took an X-ray crystallographic of DNA (Photo 51)
• revealed its double helix structure
• but she received no credit for helping discover the structure.

Question 3

Avery

Answer 3

Discovered that DNA was the transforming factor in Griffith’s experiment
(carries genetics instead of proteins )

Question 4

Chargaff

Answer 4

discovered ‘Chargaffs rules’ (below)

1. Regardless of the organism A=T G=C
2. The composition of DNA varies between species

Question 5

Watson & Crick

Answer 5

structure of DNA.

Question 6

What is the importance of DNA replication

Answer 6

• it makes more DNA for our cells, so they can grow and repair themsevles.
• when a cell divides the original DNA from the parent DNA must copy and go on.
• carries our genetic code, which means our traits are determined by the DNA, so we wouldn’t be able to function without DNA.

Question 7

Adenine pairs with….

Guanine pairs with….

Answer 7

Adenine pairs with. Thymine
Guanine pairs with. Cytosine
A=T
G=C

Question 8

An analogy for the structure of DNA is the sides of the ladder are made of ___ and ___ and the steps of the ladder are ___.

Answer 8

An analogy for the structure of DNA is the sides of the ladder are made of sugar and phosphates and the steps of the ladder are nitrogen bases.

Question 9

Each body cell in an organism has ___ DNA no matter what job it does.

Answer 9

SAME DNA

Question 10

The sugar found in DNA is named

Answer 10

deoxyribose

Question 11

What are the 3 parts of a nucleotide?

Answer 11

A phosphate, deoxyribose sugar, and nitrogen base.

Question 12

If 30% of the nucleotides in a DNA molecule contain cytosine (C), what is the approximate percentage of guanine

Answer 12

30% (because C=G and A=T)

Question 13

DNA replication results in two DNA molecules each with____

Answer 13

Each with one strand and one original strand

Question 14

A cell with a full set of chromosomes is referred to as __________
a cell with half the number of chromosomes is referred to as _____________.

Answer 14

full set- diploid

half #- haploid

Question 15

What is result at the end of mitosis

Answer 15

Two identical cells with the same number of chromosomes as each other and as the original (parent) cell

Question 16

What must a cell do before it can carry out mitosis

Answer 16

Replicate its DNA

Question 17

What is the purpose of mitosis?

Answer 17

growth and repair. To make 2 identical daughter cells to replace damaged/lost cells.

Question 18

how many chromosomes do humans have total, and how many do they have after completing cell division/mitosis

Answer 18

46, the same (EXACT IDENTICAL COPY OF THE ORIGINAL CELL)

Question 19

know phases of the cell cycle

Answer 19

…

Question 20

what is the full name of DNA

Answer 20

Deoxyribonucleic acid

Question 21

helicase role in replication

Answer 21

unwinds the DNA by breaking hydrogen bonds between the two strands

Question 22

Why is DNA replication is called “semi-conservative.”

Answer 22

the new DNA molecules–> each with one new strand and one original strand.