Ch 9 Biology (Not Done)

Cell Division and sexual reproduction

Somatic Cells

Regular cells in the body, except for sperm/egg cells

Diploid

the 1st 22 pairs of chromosomes; also known as somatic cells

Haploid

the 23rd pair of chromosomes that makes up the sperm/egg cell

Gamete

sex cells 

Zygote

result of the sperm and egg cell combining

Germ Line Cell

“Put Away” cells to later become sex cells by Meiosis

Mitosis Steps Abbreviation 

PMAT

Mitosis P step

Prophase

Mitosis M step

Metaphase

Mitosis A step

Anaphase

Mitosis T step

Telophase

Prophase

Chromosomes come to the center

Metaphase

Pairs have found eachother

Anaphase

Chromosomes are pulled apart

Telophase

Cell division is completed (1 cell becomes 2)

Checkpoint Phases

G1, S, and G2

Checkpoint G1

Double cellular content

Checkpoint S

Duplicate DNA

Checkpoint G2

Double proteins (boring stage)

Apoptosis Definition 

Death of the cells

2 Mechanisms for cell death 

1. Intrinsic

2. Extrinsic 

Intrinsic definition

Internal killing of the cells

Extrinsic definition

External killing of the cells

Where and what happens in Intrinsic?

Mitochondria blows up releasing something which then pokes holes in the cell membrane

Where and what happens in Extrinsic?

The Immune System, using phagocytes, eats the cell

Phagocyte definition

security guard

Fertilization 

Fusion of Gametes

Meiosis Definition

Process of reduction division of the cells to ensure consistent chromosomes across generations

Asexual Reproduction

Does not involve gametes,. Ex. Bacteria

Asexually and Sexually 

ex. plants 

Mitotic Spindle 

Pulls chromosomes apart 

Meiosis happens how many times?

2

Meiosis 1

Creates 2 diploid cells that are not identical. DNA is replicated

Meiosis 2

Create 2 Haploid cells. Create 4 Haploid from 1 diploid cell all completely unique

Meiosis Prophase 1

Chromosomes line up as pairs and do Crossing over

Crossing over Definition 

chromosomes switch arms 

Meiosis Metaphase 1

Chromosomes pair together by chance (different possible outcomes)