Chapter 3 Section 5

Question 1

Describe the cell cycle

Answer 1

??

Question 2

What occurs in the first stage of the cell cycle: Interphase

Answer 2

The cell grows and chromosomes are duplicated through the process of DNA replication. (See Mitosis notes page)

Question 3

Explain replication

Answer 3

DNA makes a copy of itself.
DNA replication is the cell’s process of making a copy of its DNA during INTERPHASE right before entering mitosis. This way when the cell splits in 2, both new cells have the right amount of DNA.

Question 4

The 2nd stage of the cell cycle is called

Answer 4

Mitosis

Question 5

What occurs during mitosis?

Answer 5

The cell’s nucleus is divide into 2 new nuclei

Question 6

What are the 2 rod structures that contains the cells DNA called?

Answer 6

Chromosome

Question 7

What is each rod called?

Answer 7

Chromatid

Question 8

Mitosis is divided into 4 parts. Name and describe those parts.

Answer 8

Prophase: the nuclear membrane begins to dissolve.
Metaphase: the chromosomes line up at the equator of the cell.
Anaphase: the chromatids separate and move to opposite sides of the cell.
Telophase: a nuclear membrane forms around each set of chromosomes and the chromosomes unwind.

Question 9

Name and describe the 3rd stage of the cell cycle

Answer 9

Cytokinesis: the cell pinches into 2 new cells

Question 10

Contributions from Scientists:

Franklin

Answer 10

used x ray to see DNA

Question 11

Contributions from Scientists:

Chargaff

Answer 11

said that A=T and G=C

Question 12

Contributions from Scientists:

Watson & Crick

Answer 12

made a model of DNA

Question 13

The structure of DNA is described as a _____. It is made out of many smaller______ linked together. A ____ is a subunit of DNA.

Answer 13

Twisted ladder
Nucleotides
Nucleotide

Question 14

Nucleotides are made of:
Ladder sides:
Ladder rungs:

Answer 14

Phosphate and Sugar

base

Question 15

List the 4 bases (be sure to list which are complimentary)

Answer 15

Adenine=Thymine

Guanine=Cytosine

Question 16

DNA replication is the cell’s process of making a copy of its DNA during ______ right before entering mitosis. This way when the cell splits in 2, both new cells have the right amount of DNA.

Answer 16

INTERPHASE

Question 17

4 steps of DNA replication

Answer 17

A. Proteins unwind the DNA
B. DNA is split down the middle by proteins
C. complementary strands are added to both sides of the open DNA. The final result is 2 helices, each containing a OLD strand and a NEW strand.
D. The DNA is then rewound by proteins.

Question 18

How many meters or feet of DNA does each cell contain

Answer 18

6-8 feet

Question 19

How does a single cell fit the entire DNA into the nucleus?

Answer 19

It winds up tightly.