B6 Inheritance v1

Question 1

what is DNA

Answer 1

it is the chemical that contains all the genetic information of the cell

Question 2

describe the make up of your DNA

Answer 2

It is a polymer which is made up of two strands coiled together to make a double helix

Question 3

what is a gene

Answer 3

a small section of DNA found on a chromosome. It codes for a specific protein

Question 4

how many different amino acids can a gene code for

Answer 4

20

Question 5

what do genes specifically tell cells

Answer 5

what order to put the amino acids, which potentially make up 1000’s of different combinations

Question 6

define a genome

Answer 6

the collective term for the entire set of genetic material in an organism

Question 7

2 reasons why understanding the human genome is helpfull

Answer 7

Helps scientists to track inherited disease and trace the migration of people

Question 8

What is the monomer for DNA

Answer 8

nucleotides

Question 9

what three things do a nucelotide contain

Answer 9

one sugar molecule, one phosphate molecule and one ‘base’

Question 10

what are the two possible pairings of bases according to ‘complementary base pairing’

Answer 10

A and T. C and G

Question 11

what does the mRNA do

Answer 11

it acts as a messenger between the DNA and the ribosome, carrying the code to make proteins

Question 12

three functions of proteins

Answer 12

enzymes(act as biological catalysts). Hormones (used to carry messages around the body). structural proteins

Question 13

what is a mutation

Answer 13

a random change to an organisms DNA code

Question 14

what specifically does a mutation do

Answer 14

It changes the sequence of DNA bases in a gene

Question 15

why might the function of a protein be affected by a gene mutation

Answer 15

because the bases of DNA codes the sequence of amino acids which make up a protein

Question 16

what does an insertion mutation do

Answer 16

it changes the the groups of three bases are read

Question 17

what are the three types of genetic mutation

Answer 17

insertion, deleteions, substitutions

Question 18

what do the mother and father create during sexual reproduction

Answer 18

gametes

Question 19

how many chromosomes does. gamete contain

Answer 19

23

Question 20

what type of cell division occurs in sexual reproduction

Answer 20

meiosis

Question 21

what type of cell division occurs in asexual reproduction

Answer 21

mitosis

Question 22

describe the first three steps of meiosis

Answer 22

“1- before the cell divides it duplicates its genetic information, forming two armed chromosomes. 2- for the first
division the pairs then line up in the centre of the cell. 3- the pairs are then pulled apart therefore forming two
cells with the same genetic information”

Question 23

describe the final three steps of meiosis

Answer 23

“1- for the second division, chromosmes line up again but this time the arms are pulled apart. 2- you then end up
with four gametes with different genetic information as the chromosomes have been shuffled up during meiosis”

Question 24

two advantages sexual reproduction has over asexual reproduction

Answer 24

“1- Mixture of chromosomes from both parents causes variation. this causes increased survival rates.
2- better survival rates means breeding spread survival characteristics through variation”

Question 25

two advantages asexual reproduction has over sexual reproduction

Answer 25

only needs one parent, less energy needed to find a mate, can happen faster

Question 26

what is the combination of chromosomes that makes you a male

Answer 26

XY

Question 27

what is the combination of chromosomes that makes you a female

Answer 27

XX

Question 28

what is an allele

Answer 28

the part of a gene from 1 chromosome,

Question 29

how many copies of each chromosome does a gene have

Answer 29

2

Question 30

what is your genotype

Answer 30

the combination of alleles you have

Question 31

what is your phenotype

Answer 31

the set of characteristics you have as a result of your combination of alleles

Question 32

what does it mean if two alleles match

Answer 32

it means they have the trait

Question 33

if an allele for a disorder is recessive, what does that mean for people with only of the allele

Answer 33

it means they do not have it but could carry it as when breeding , it could match with another allele of the same kind

Question 34

what is a dominant allele

Answer 34

a gene that produces its effect in the presence of the other (recessive) allele