Biology - Topic 3 - Genetics Flashcards Preview

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Flashcards in Biology - Topic 3 - Genetics Deck (67)
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1

Which structures are found inside the nucleus?

chromosomes

2

Which substance forms a long strand in each chromosome?

DNA

3

How do body cells make copies of themselves?

cell division, mitosis

4

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

46

5

What happens in fertilisation?

two gametes fuse

6

What is the name of the cell formed in fertilisation?

zygote, fertilised egg cell

7

Which term means producing more of the same kind of organism?

reproduction

8

What is the name of the human male gamete?

sperm cell

9

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

genes

10

What would happen to the number of chromosomes in a zygote if two body cells were used in fertilisation?

it would have twice the number it should

11

How many chromosomes does a human gamete
contain?

23

12

Where are genes found?

(in sections of DNA) on chromosomes

13

What does a gene carry the instructions for?

making a protein

14

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

amino acids

15

What is any molecule made of repeating units called?

a polymer

16

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

diploid

17

Are the cells produced by meiosis haploid or diploid?

haploid

18

Are the cells produced by mitosis haploid or diploid?

diploid

19

What shape is DNA?

double helix

20

What is a chromosome made out of?

DNA and proteins (to package the DNA)

21

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

A, C, T and G

22

How do the bases pair up in DNA?

A with T, C with G

23

Apart from bases, what other parts are needed in a DNA molecule?

phosphate group, sugar

24

What is one phosphate group, one sugar and one base called?

nucleotide

25

How is the active site of an enzyme formed?

by folding of protein/polypeptide/amino acid chains

26

What molecule is produced in transcription?

mRNA or messenger RNA

27

What base does mRNA contain that DNA does not?

uracil

28

What is the name of the enzyme that allows
transcription to occur?

RNA polymerase

29

The mRNA nucleotides fit together with the nucleotides on the DNA template strand. What word describes bases that fit together?

complementary

30

Where does transcription occur in a cell?

nucleus