DNA, RNA and Mutations

Question 1

What does DNA stand for?

Answer 1

Deoxyribonucleic acid

Question 2

How long is DNA from one human cell when stretched?

Answer 2

3 meters

Question 3

What is the structure of DNA described as?

Answer 3

Double helix- each rung on the ladder is a base

Question 4

What are the four nucleotide bases in DNA?

Answer 4

• Adenine (A) * Cytosine (C) * Guanine (G) * Thymine (T)

Question 5

Where are chromosomes located?

Answer 5

In the nucleus of cells

Question 6

What is a chromatid?

Answer 6

One half of two identical or ‘Sister’ chromatids

Question 7

Every species has a characteristic number of chromosomes, how many pairs of chromosomes do humans have?

Answer 7

23 pairs (46)

Question 8

What can happen to hybrids with uneven chromosomes?

Answer 8

They can become infertile

Question 9

What is DNA replication?

Answer 9

The process of copying DNA for cellular division, producing an identical copy of the original cell apart from mutations

Question 10

What is a mutation?

Answer 10

A change in the arrangement of bases in a gene or a change in chromosome structure

Question 11

What is the pattern of complementary base pairings in DNA?

Answer 11

Each strand has a sequence that pairs with its complementary base

Question 12

What does RNA stand for?

Answer 12

Ribonucleic acid

Question 13

What bases does RNA consist of?

Answer 13

• Adenine (A) * Cytosine (C) * Guanine (G) * Uracil (U)

Question 14

What is the difference between RNA and DNA regarding structure?

Answer 14

•RNA is single stranded, DNA is double stranded

•RNA contains uracil while DNA contains thymine

•Viruses/pathogens have RNA but don’t have DNA

Question 15

What is a codon?

Answer 15

A sequence of 3 consecutive bases that codes for an amino acid

Question 16

What percentage of human DNA does not carry the code for protein production?

Answer 16

97%

Question 17

What is a same sense mutation?

Answer 17

A mutation that leads to a change in bases but still codes for the same amino acid

Question 18

What is a mis-sense mutation?

Answer 18

A mutation that causes a change in amino acid

Question 19

What is a non-sense mutation?

Answer 19

A mutation that changes a codon that codes for an amino acid to a stop codon

Question 20

What is a frame shift mutation?

Answer 20

A mutation (insersion or deletion) that alters the reading frame of the DNA

Question 21

What is a duplication mutation?

Answer 21

A mutation where a segment of DNA is duplicated

Question 22

What is inversion in chromosome mutations?

Answer 22

The position of genes are swapped

Question 23

What is translocation in chromosome mutations?

Answer 23

Parts of two chromosomes break off and swap places

Question 24

How do mutations occur?

Answer 24

•Most occur when DNA fails to replicate properly

•DNA can break down in the most pristine environments (not always unnatural)

•When a cell repairs it is not a perfect job

•chemicals and radiation

Question 25

What external factors can cause mutations?

Answer 25

Chemicals or radiation which cause DNA to break down

Question 26

True or False: Mutations can be advantageous.

Answer 26

True

Question 27

Fill in the blank: A sequence of three bases codes for _______.

Answer 27

[an amino acid]

Question 28

What happens during DNA repair?

Answer 28

It is not always perfect, leading to potential mutations.

Question 29

What are chromosomes made up of?

Answer 29

Thread like structures made of DNA

Question 30

What do codons code for?

Answer 30

An amino acid, 1 codon= 1 amino acid

Question 31

What ways can mutations alter base pairs?

Answer 31

•Exchange one base for another •Extra base pairs inserted into a new place in the DNA •Sections of the DNA is lost or deleted

Question 32

What are the different chromosome mutations?

Answer 32

•Duplication •Inversion •Translocation

Question 33

True or false? Most mutations do not improve or worsen the chances of survival so have little effect

Answer 33

True

Question 34

True or false? Mutations always cause little or no damage

Answer 34

False- mutations can cause lots of damage