Biology Cell Cycle, Chromosomes, Mitosis and

What is a Karyotype

A tool used to reach chromosomes to find missing or extra chromosomes

How is a karyotype used to diagnose genetic condition

It is done through either a blood test from mom or a procedure called amniocentesis

Trisomy

3 homologous chromosomes instead of 2. Occurs during anaphase 1 (non disjunction)

What phases of the cell cycle make up interphase?

G1 phase, S phase, G2 phase

What is happening during each phase of cell cycle in interphase

G1 phase - 1st growth phase

S phase - DNA is replicated

G2 phase - second growth phase

Cancer

An uncontrolled growth of cells

Checkpoints to prevent cancer

G1, G2, metaphase

Metastasis

When a tumor & cancer cells spread to other parts or the body

The type of cells that go through mitosis

Somatic

Somatic cells

Every cell in the body except egg and sperm cells

The type of cells that are created in mitosis

Diploid

Diploid

2 sets of chromosomes/ pairs of chromosomes instead the cell

Haploid

A cell that has half the number of chromosomes (sex cells)

Gametes

Sex cells that have only individual chromosomes. One from each homologous pair

What process does the body use mitosis for?

Growth, development, and repairs

Phases of mitosis (in order)

PMAT

Prophase, metaphase, anaphase, telophase

What happens in prophase

DNA is bundles into chromosomes

Nuclear membrane begins to dissolve

Centrioles migrate to the poles of the cell

What happens during metaphase

Newly formed chromosomes line up on the equator of the cell

The centimeter of each chromosome attaches to the centrioles though structures called spindle fibers

What happens in anaphase

Centromere dissolves and spindle fibers pull chromatids towards the centrioles

What happens during telophase

Chromatids are in opposite poles and begin to unravel. Nuclear membrane begins to reform

What happens during cytokinesis

Very last phase of cell cycle

The division of the cytoplasm in the cell itself

Looks different in plant and animal cells

Two goals of meiosis

Division and creation of gametes

How is metaphase 1 of meiosis different from metaphase of mitosis

There are two chromosomes

What happens during synapsis

The process of the chromosomes lining up

How does crossing over benefit a species

Lends itself to genetic diversity within a species

When can a nondisjunction occur

Anaphase 1

What happens during a nondisjunction & how does it affect the chromosome number

Creates a cell with a missing or extra chromosome at the end of meiosis

After meiosis 1 how many cells are there

2 identical cells

How many chromosomes does each cell have after meiosis 1

2 chromosomes

How us metaphase 2 similar to mitosis

The chromosomes line up on the equator

How many cells are formed at the end of meiosis 2

Four cells

Cancer

The uncontrolled growth of cells

How does the cell cycle control cancer/ tumor formation?

During G2 phase the cell cycle has checkpoints which will stop a mutated cell from dividing. If this checkpoint is turned off, a tumor will form

Metastasis

When a tumor spreads to other parts of the body

Benign tumor

Not cancerous

Malignant tumor

Cancerous that can metastasize

How is genetic variation beneficial to a population/species

Reduces the prevalence of genetic diseases, decreased the odds of inheriting

Increase the populations resistance to infectious disease

Makes the populations as a whole healthier