Chapter 4.1

Question 1

What are the 4 things that the master set of instructions in the nucleus determine?

Answer 1

1. What each will become
2. How each cell with function
3. When will each cell grow and divide
4. When each cell will die

Question 2

What does DNA stand for?

Answer 2

Deoxyribonucleic Acid

Question 3

What is the function of DNA?

Answer 3

Carries the instructions for cell function

Question 4

What does DNA look like?

Answer 4

A twisted ladder

AKA Double Helix

Question 5

What is DNA made up of?

Answer 5

1. the sides of the ladder are made of phosphate and sugar

2. the steps of the ladder are made of 4 nitrogen bases

Question 6

What are the 4 nitrogen bases?

Answer 6

A - Adenine
G - Guanine
C - Cytosine
T - Thymine

Question 7

What is a DNA message?

Answer 7

The arrangement of nitrogen bases on the DNA

Question 8

How do the bases always join together?

Answer 8

A always pairs up with T.

G always pairs up with C.

Question 9

In what form does DNA exist in the nucleus?

Answer 9

Chromatin

Question 10

What is within each strand of chromatin?

Answer 10

One molecule of DNA

Question 11

What happens to the chromatin when the cell is ready to divide?

Answer 11

The chromatin coils up into compact, x-shaped chromosomes

Question 12

How many chromosomes does a human have?

Answer 12

46 (23 pairs)

Question 13

How do you determine the gender/sex?

Answer 13

The 23rd pair of chromosomes determines the sex.
Male = XY
Female = XX

Question 14

Where are genes located?

Answer 14

Specific places on a chromosome, every chromosome carries thousand of genes

Question 15

What do genes do?

Answer 15

Store the information needed to produce different proteins

Question 16

Your skin and muscle cells contain identical DNA. How are these cells able to function differently?

Answer 16

Each cell contains identical DNA but only specific genes are “read” in each cell to produce specific proteins.
By making specific proteins, a cell becomes specialized to carry out a particular function.

Question 17

What are enzymes and hormones?

Answer 17

Specialized proteins

Question 18

How are proteins produced?

Answer 18

1. Nucleus receives a chemical signal to make a specific protein
2. DNA message for a specific protein is copied into a small molecule called RNA
3. RNA leaves through a nuclear pore
4. RNA message is delivered to the ribosome and the ribosome makes the protein
5. Manufactured protein enters the endoplasmic reticulum
6. Vesicle forms off the end of the endoplasmic reticulum and carries the protein to the golgi body
7. Golgi body repackages protein for transport out of the cell
8. Vesicle forms off the end of the golgi body to carry the protein to the cell membrane
9. Vesicle attaches to the cell membrane and its protein contents are released out of the cell

Question 19

What does RNA stand for?

Answer 19

Ribonucleic acid

Question 20

What is chromatin?

Answer 20

A substance that contains DNA and proteins