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Flashcards in biology Deck (35):
1

chromosome

the thread like structure of DNA containing the genes

2

double helix

shape like a twisted rope ladder, made of two sugar phosphate backbones

3

DNA

- deoxyribonucleic acid
- the compound chromosome are made of
- it is the blueprint of life, tells the body what, when and how to build something how much to build and how long for

4

diploid

2n
46 in humans, 44 autosomes and 2 sex chromosomes

5

haploid

n
23 egg and sperm

6

gamete

sperm and egg cells

7

gene

- portions of dna make up genes
- contains your traits and characteristics

8

mitosis

- cell division for growth or repair
- same chromosome number

9

mutation

a mistake that happens when dna is being copied causing damage to the base sequence

10

nucleus

where chromosomes are found

11

nucleotide

- one portion of a stand of dna
- made up of deoxyribose sugar, phosphate and a base

12

nitrogenous base

- part of a nucleotide
- four types

13

phosphate

one of the parts that make up a nucleotide

14

replication

process of copying cells

15

molecules of the nucleus

all living things have slightly different versions of the same molecules in the nucleus of their cell

16

what is dna and what does it do

- deoxyribonucleic acid
- controls the way organisms look and function
- determines characteristics
- contributes to the diversity and variety of living things
- has similar structure in all organisms

17

what is a nucleotide

- the basic building block of dna
- has three parts, base, deoxyribose sugar and phosphate
- arranged in such a way that gives the dna molecule a double helix
- the bases always pair in the same way

18

first stage of cell division

-

19

diploid number

human body cells each contain 23 pairs or 46 chromosomes

20

what is a chromosome made of

- composed of many genes
- genes are sections of dna

21

what is the difference between one gene and another

the number and order of the bases along the dna stand

22

what does a gene contain

a gene contains the code for building a protein which controls a characteristic or function in the body

23

what is mutation

mutations are changed in the bases of genes or to chromosomes

24

what is mitosis

- is cell division in the body cells for growth and repair
- it produces two identical cells

25

how do remember the stages of mitosis

i party most at the club

26

what are the six stages of mitosis

1. interphase
2. prophase
3. metaphase
4. anaphase
5. telophase
6. cytokinesis

27

what does the first stage do

- dna coils up
- doubling the dna
- 46 turns to 92 which are sister chromatids

28

what happens in the second stage

-the replicated chromosome and their chromatids become visible
- membrane disappears
- they link together

29

what happens in the third stage

replicated chromosomes line up along the middle of the cell
- original on one side
- duplicated on the other
but still joint together
- attached to a fibre (line)

30

what happens in the fourth stage

- the chromatids separate and move to opposite poles of the cell
- each chromosome split in half

31

what happens in the fifth stage

2 nuclei form each with the same number of chromosomes as the parent cell

32

what happens in the sixth step

- cell membranes form making 2 daughter cells
- each with a nucleus

33

what is a chromatid

- when they are duplicated and then join with the duplicated chromosome

34

allele

different version of the same gene

35

what are the four bases

thymine
adenine
cytosine
guanine