Topic 3 - Genetics

Question 1

what are found inside the nucleus?

Answer 1

chromosomes

Question 2

Which substance forms a long strand in each chromosome?

Answer 2

dna

Question 3

How do body cells make copies of themselves?

Answer 3

mitosis

Question 4

How many chromosomes are there in a human body cell nucleus?

Answer 4

46

Question 5

what happens in fertilisation?

Answer 5

two gametes fuse

Question 6

what is the cell formed in fertilisation called?

Answer 6

zygote

Question 7

what is the name of the human gamete?

Answer 7

sperm cell

Question 8

The DNA strand in a chromosome contains sections that carry instructions for characteristics. What are these sections called?

Answer 8

genes

Question 9

What molecule forms the genome of an organism?

Answer 9

dna

Question 10

where are genes found?

Answer 10

[in sections of DNA] on chromosomes

Question 11

What does a gene carry the instructions for?

Answer 11

making a protein

Question 12

A protein is made by linking together smaller molecules. What are these smaller molecules called?

Answer 12

amino acids

Question 13

what is a group of molecules joined together called?

Answer 13

a ploymer

Question 14

A human cell contains 46 strands of DNA. Is it diploid or haploid?

Answer 14

diploid

Question 15

are the cells produced by meiosis haploid or diploid?

Answer 15

haploid

Question 16

Are the cells produced by mitosis haploid or diploid?

Answer 16

diploid

Question 17

What shape is DNA?

Answer 17

double helix

Question 18

What is a chromosome made out of?

Answer 18

dna and proteins

Question 19

What are the letters of the bases that form the DNA code?

Answer 19

A,C,T,G

Question 20

How do these bases pair up in DNA?

Answer 20

A&T , C&G

Question 21

Give an example of a protein

Answer 21

enzymes

Question 22

how is the active site of an enzyme formed?

Answer 22

folding of protein

Question 23

why are proteins polymers

Answer 23

they are made of many amino acids joined in a chain

Question 24

how many bases does a codon contain?

Answer 24

3

Question 25

whats a mutation

Answer 25

a change in the bases of a gene that creates a genetic variant

Question 26

whats an organisms phenotype?

Answer 26

its observed characteristics

Question 27

whats an organisms phenotype?

Answer 27

its observed characteristics

Question 28

what are different versions of the same gene called?

Answer 28

alleles

Question 29

what sort of variation do alleles cause in organism

Answer 29

genetic variation

Question 30

what word describes both alleles are the same?

Answer 30

homozygous

Question 31

if a dominant allele has the letter A, how would u show an organism is heterozygous?

Answer 31

Aa

Question 32

what word describes the characteristics of a gene?

Answer 32

a phenotype

Question 33

what word describes the alleles of a gene found in an organism

Answer 33

genotype

Question 34

whats a recessive allele

Answer 34

a

Question 35

a genotype is written QQ. What does this tell you?

Answer 35

It is homozygous and dominant

Question 36

whats probability?

Answer 36

the chance of an event happening

Question 37

how can we show the possible offspring through two peoples alleles?

Answer 37

punnett square

Question 38

what do x and y chromosomes make?

Answer 38

male

Question 39

probibalitly of having a boy

Answer 39

50%

Question 40

Formation of DNA

Answer 40

- Two strands coil to form a double helix - Strands linked by complimentary base pairs - Base pairs joined by weak hydrogen bonds

Question 41

What are the DNA bases made out of

Answer 41

Sugar & phosphate

Question 42

How are the base pairs joined together?

Answer 42

Weak hydrogen bonds

Question 43

What’s the first step of extracting DNA from fruit?

Answer 43

Use detergent to break down cell membrane and release DNA

Question 44

Why do you add salt when extracting DNA in fruit cells

Answer 44

Salt makes the DNA stick together

Question 45

What’s the last step of extracting DNA from fruit cells?

Answer 45

Add ice-cold ethanol

Question 46

Why do You add ethonal to fruit cells?

Answer 46

because the DNA isn’t soluble in cold alcohol

Question 47

What happens after alchol has been added?

Answer 47

It will appear as a white stringy precipitate

Question 48

4 stages of genetic engineering

Answer 48

1. Gene extracted using restricted enzyme 2. Plasmid extracted from bacterial cell 3. Enzyme used to cut open plasmid 4. Gene inserted into plasmid, sealed by an enzyme.