Chapter 8.2 The Genetic Code New Material

Question 1

What are proteins?

Answer 1

Long-chain molecules made of individual amino acids

Question 2

What determines what type of protein will be produced?

Answer 2

The order of the nitrogen bases along a gene forms a genetic code that specifies what type of protein will be produced

Question 3

What is a codon?

Answer 3

A group of 3 bases in the genetic code that codes for one specific amino acid
Ex. CGT = amino acid Alanine

Question 4

The first 3 codon determine the specific amino acid that will be produced. What do the other codon determine?

Answer 4

The order in which the amino acids are put together to form a protein

Question 5

How many different amino acids are in the human body?

Answer 5

20

Question 6

What does your body use amino acids for?

Answer 6

To make different types of proteins needed to carry out cell processes.

Question 7

What is protein synthesis?

Answer 7

When the amino acids link to form proteins

Question 8

Where does the process of protein synthesis begin?

Answer 8

INSIDE the nucleus where DNA contains the code for the protein

Question 9

Where does the assembly of the protein occur?

Answer 9

OUTSIDE the nucleus on a ribosome

Question 10

How does the blueprint for making a protein get from the nucleus to the ribosome?

Answer 10

By a nucleic acid called RNA (ribonucleic acid)

Question 11

How is RNA different from DNA?

Answer 11

RNA contains the sugar ribose instead of deoxyribose

Question 12

What nitrogen base is different berween RNA and DNA?

Answer 12

RNA had uracil (U) instead of thymine (T)

Uracil (U) is the complement to adenine (A) in RNA

Question 13

What are the two types of RNA?

Answer 13

mRNA - messenger RNA

tRNA - transfer RNA

Question 14

What is mRNA

Answer 14

Messenger RNA carries copies of instructions for the assembly of amino acids into proteins from DNA to ribosomes in the cytoplasm

Question 15

What is tRNA?

Answer 15

Transfer RNA carries amino acids to the ribosome during protein synthesis.

Question 16

What is an mRNA codon table?

Answer 16

It is a table used by scientists to determine which codons will code for each amino acid.

Question 17

What is a mutation?

Answer 17

Any change in a gene or chromosome.

Question 18

How do mutations occur?

Answer 18

They can be inherited from a parent or acquired during an organism’s life.

Question 19

What are inherited mutations?

Answer 19

1. Occur when the parent passes on the mutation during reproduction.
2. Present through the life of the organism
3. Present in every cell of the body

Question 20

What are acquired mutations?

Answer 20

1. Occur at some point during an organism’s lifetime
2. Can only be passed on from parent to offspring if the mutations occur in sex cells
3. Are not present in every cell of the body

NOTE: number 2 does not make sense to Mom
Acquired mutations can be caused by environmental factors such as ultrviolet radiation from the sun or if an error is made when DNA copies itself during cell division

Question 21

What causes mutations?

Answer 21

Many mutations are the result of a small change in the organism’s DNA sequence.
Mutations include deletion, addition or substitution.

Question 22

What may happen if there is a small change to a base pair in DNA?

Answer 22

An incorrect protein may be made during protein synthesis

Question 23

What are sex-linked mutations?

Answer 23

They occur on sex-linked genes which are on the sex chromosome

Question 24

Which chromosome do most sex-linked mutations occur?

Answer 24

The x chromosome because it has more genes than the y chromosome.

Question 25

Are sex-linked mutations dominant or recessive?

Answer 25

Recessive

Question 26

What are some examples of sex-linked mutations?

Answer 26

Hemophilia - ability of blood to clot is reduced

Color-blindness