Teacher mitosis

Cell Reproductio

n Notes

Prokaryotic Cell Reproduction

• Prokaryotes reproduce by _binary fission.

• Produced identical offspring

• First the DNA is copied

• New cell membrane is added to pinch the cell into two daughter cells.

Eukaryotic Chromosomes

What are chromosomes made of? ___DNA______________

What is a gene? _SEGMENT OF DNA______

___________

Which organism has the most chromosomes?__________least?___________

Human Chromosomes (karyotype)

Is this a karyotype of a male or female?

What is the difference between male and female?

Sets of Chromosomes• Humans have 23 sets of two chromosomes• One of each pair came from each parent.• _SOMATIC_ cells (body cells) all contain 46

chromosomes• __sex__ chromosomes (sperm and egg) are

haploid, they contain 23 chromosomes each.• When sex chromosomes combine they form

a diploid _ZYGOTE.

Chromosomal Mutations

What do the different sections represent?

What went wrong in each mutation?

sickle-cell disease is caused by a single point mutation which encodes the amino acid valine rather than glutamic acid.

Chromesome number sheet

Organism

# of chromosome

s in body, skin cells,

etc.

2N Diploid #

1N Haploid #

# of chromosomes in sperm

cells

# of chromosomes in egg cells

Fruit fly 8

Onion 8

Cat 38

Chicken 38

human

apple 34

Cat fish 20

Chromesome number sheet

Organism

# of chromosome

s in body, skin cells,

etc.

2N Diploid #

1N Haploid #

# of chromosomes in sperm

cells

# of chromosomes in egg cells

Fruit fly 8 8 4 4 4

Onion 16 16 8 8 8

Cat 38 38 19 19 19

Chicken 76 76 38 38 38

human 46 46 23 23 23

apple 34 34 17 17 17

Cat fish 20 20 10 10 10

Cell CycleFirst Growth Phase (G1)

•Cell grows rapidly

•Normal cell functioning

•Major portion of life

Synthesis Phase (S)

•DNA is copied

•Each chromosome = 2 chromatids attached at centromere

Second Growth Phase (G2)

•Organelles replicate

•Microtubules form spindle to move chromosomes during mitosis

Mitosis

• cell nucleus divides

Cytokinesis

• cytoplasm divides

Phases of

Mitosis

Chromosome during Mitosis

Phases of

Mitosis

Phases of

Mitosis

Meiosis – Cell reproduction of sex cells.

Meiosis Mitosis

Start with 2N cells, end with 1N cells (haploid.)

Start with (diploid) 2N cells, End with 2N cells

# of chromosomes in cells produced is reduced by half.

Chromosome # stays the same.

Creates 4 egg or sperm cells Creates 2 identical daughter cells

2 Cell divisions involving InterphaseProphaseMetaphaseAnaphasetelophase

1 cell division involving InterphaseProphaseMetaphaseAnaphasetelophase

Meiosis 1

Meiosis 2