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Flashcards in Cell Reproduction Deck (60)
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1

How do cells reproduce?

Dividing

2

What are gametes?

Sex cells
(sperm and ova)

3

What does an ova and a sperm fuse toegether to create in sex?

Zygote

4

How do fungi and bacteria reproduce?

Asexually

5

Define the cell cycle

The period between the formation of a new cell and when it divides into daughter cells

6

Run through the cell cycle

G1
SYNTHESIS
G2
MIITOSIS
CYTOKENSIS

7

Where does DNA replication occur?

in the synthesis stage

8

What makes up the largest part of the cell cycle?

Interphase

9

Define Mitosis

A type of cell division in which two identical daughter cells are prodcued.

10

What are somatic cells also known as?

Diploid

11

What are the three functions of mitosis?

Growth
Repair
Asexual Reproduction

12

Summarise the process of mitosis

Chromosomes duplicate
Sister chromatids separate
Nucleus divides

13

What are the autosomes?

Chromosomes1-22

14

Male chromosmes

XY

15

Female Chromosomes

XX

16

What is chromatin?

The subtance that makes up chromastids

17

What does mitosis produce?

Two daughter diploid cells

18

What does meiosis produce?

4 daughter haploid cells

19

Explain interphase for mitosis

-Cell is performing whatever job it is designed to do
-DNA replicates and begin to condense at the end of interphase

20

What can be seen for the interphase stage on mitosis

Individuals cannot see te chromosomes yet they can see the chromatin blob

21

What happens in mitosis in prophase I

Chromosomes begin to shorten and condense and therefore become much easier to see
-Nuclear mmembrane breaks down thus allowing the chromsomes to move around the cell

22

What is formed during prophase?

A spindle forms which is controlled by the centrioles.

23

Explain what happens at metaphase I in mitosis

Spindle fibres latch onto the chromosomes and line along the eqautor.
The spindle fibres attach the to the centro meters

24

Explain what is happening in anaphase 1 in mitosis

Spindle fibres contract which spikes the chromosmes into seperate chromatids
the derogate chromastids are then drawer to either end of the cell

25

Explain what's happening at telophase I in mitosiss

Two goes of chromosomes will unravel and become blobs of chromatin.
Nuclear membrane reforms and is create around the two groups

26

Define Meiosis

The division of diploid parent cells to produce four, non-identical haploid cells

27

What does meiosis produce?

Gametes

28

What type of division is meiosis

Reduction

29

diploid number

2n

30

haploid number

n

31

Explain a haploid cell

Contains a single set of chromsomes and has half the amount of the genetic materials

32

Explain a diploid cell

Two complete sets of chromosomes

33

What are homogenous pairs.

Chromosomes carrying the same gene

34

When are female gametes produced..

In development from zygote to child

35

When are male gametes produced?

constantly all throughout their life

36

Define crossing over

Involves the breaking and rejoining of chromatids

37

When does crossing over occurr?

Prophase I of meiosis

38

Define tetrad

A molecules in which is produced during crossing over

39

what is a chiasma

the crossing over and intersection point between two chromatids

40

Explain interphase for meiosis

DNA replicates in which each chromosome becomes a pair of chromatids

41

Explain Prophase I for meiosis

Chromosomes condense
Nuclear membrane fragment
Spindle is formed
Homologous pairs pair and up and cross over

42

What is the purpose of crossing over?

Genetic Variation

43

Explain what happens in metaphase I? for meiosis

Chromosomes line up. along the equator in homologous pairs

44

Anaphase I meiosis

homologous chromosomes seperate and one piece of each pair will move to either end of the cell

45

Telophase I for meiosis

Nuclear membrane begins to form

46

prophase II for meiosis

Nuclear membrane breaks down and spindles reform

47

Metaphase II for meiosis

Paired chromatids line the equator attached by a spindle to their centromere

48

Anaphase II

chromatids move to opposite ends of the poles due to spindles contracting

49

A telophase II for meiosis

Nuclear membrane reforms

50

Define reproduction

Production of futher members of the same species via asexual or sexual reproduction

51

Examples of axsexual reproduction

-Binary fission
-Mitosis

52

What is binary fission

-How prokaryotes replicate

53

explain binary fission

Single chromosome replicates , DNA polymerase replicates it.

54

What occurs in G1 phase>?

Cells double in size

55

What occurs in S phase

Dna and associated proteins replicate

56

What occurs in G2 phase?

Chromosomes begin to condense.

57

What is cytokinesis?

Follows telophase, daughter cells grow to reach regular size

58

Explain how crossing over leads to genetic variation (Recombnation)

In prophase 1 hoomologous chromosomes pair, make contact and can become intertwined.
Genetic material can be swapped for the corresponding material
This can lead to new combinations of genetic material on a chromosome

59

Define chiasma

The point of crossing over in prophase.

60

Explain how independent assortment can lead to variiation

Pairs of homologous chromosomes assort independently at metaphase 1 and this results in variation.