Honors biology - cell growth and division

G1 phase

Cell growth

S phase

Dna relpication

G2 phase

Preperation for mitosis

Mitosis

Cell division

What is the cell cycle?

The process of copying cells and dividing them.

When does danger replicated in the cell cycle?

S phase

Do all cells undergo cell division (mitosis) after interphase?

No, some cells enter the G0 phase

Diploid

Cells that have 2 sets of chromosomes/body cells

Haploid

Cells that have 1 sets of chromosomes/sex cells

Tetrad

Homologous pairs of each pairing / 4 chromatids

Chromosome

Condensed organized structure of dna

Chromatids

Arm of a chromosome

Centromere

Region in middle of chromosome where sister chromatids attach

Fertilization

Occurs when a sperm fuses with an egg

Prophase

Chromosomes condense ("appear")/Nuclear envelope dissolves/Centrioles move to opposite sides (poles) of the cell

Metaphase

Centrioles send out spindle fibers that attach to the chromosomes/Chromosomes are lined up in the middle of the cell

Anaphase

Chromosomes (sister chromatids) are pulled apart and move to the poles

Telophase/cytokinesis

Occurs simultaneously with each other /The nuclear envelope reforms around the chromosome /The cytoplasm divides, 2 daughter cells are produced( each one exact copies of the original w/46 chromosomes), Has 46 chromosomes

In what type of cells does meiosis occur?

Sex cells

What is the purpose of meiosis?

To produce sex cells with half the amount of chromosomes

When is the diploid number of chromosomes reduced to the haploid number of chromosomes?

End of meiosis 1

Meiosis 1 results in the separation of…

Chromosomes

Meiosis II results in the separation of…

Chromatids

Mitosis

Body cells, Diploid, Enables organisms to grow, repair damaged tissues and replace old cells, One round of cell division, Creates two genetically identical daughter cells for growth and repair, Division of nucleus, IPMAT

Meiosis

Sex cells, Produce gametes for sexual reproduction, Two rounds at nuclear division , Creates four genetically unique cells for sexual reproduction, PMAT, Two stages- meiosis 1 and 2

What are homologous chromosomes?

Pair of chromosomes with identical features , Similar but not identical , One from mom and one from dad

What are sister chromosomes?

Two identical chromatids

How does anaphase differ in meiosis 1 and II?

Meiosis 1 = moving chromosomes…….meiosis 2=moving chromatids

What does cancer have to do with the cell cycle?

The cells don't divide properly

What is a tumor?

Cells that don't divide properly

Prophase 1

Homologous pairs crossing over occurs , Chromosomes condense nuclear envelope fragments

Metaphase 1

Align along equator of cell

Anaphase 1

Separate and move to opposite poles

Telophase 1

Nuclear envelopes reappear, Spindle fibers disappear , Cytokinesis divides cell into two

Prophase II

Chromosomes appear in 2 cells

Metaphase II

Chromosomes lined up in middle

Anaphase II

Chromosomes split into chromatids

Telophase II

4 daughter cells with chromatids

A cell with two pairs of each set of chromosomes is called a

Diploid

These cells are typically found throughout the body tissues and called

Somatic cells

A cell with only one set of chromosomes is called

Haploid

These types of cells are found in the reproductive organs and are called

Germ

Sperm and egg cells are called

Gametes

A fertilized egg is a

Zygote

A type of cell division that results in diploid cells

Mitosis

A type of cell division that results in haploid cells

Meiosis

When a sperm and egg combine it is called

Zygote

What is the diploid number for humans?

46

What is the haploid number?

23

Matching chromosomes are called

Homologous pairs

During prophase I of meiosis, these pairs form a Tetrad in a process called

Crossing over

When homologous chromosomes exchange genes, it is called

Crossing over

How many daughter cells are created at the end of meiosis I

2

Meiosis II

4

During meiosis, chromosomes will split into daughter cells randomly, making each gamete unique. This is called

Genetic variation

A fertilized egg is called

Zygote

What are the key events in meiosis I?

Prophase I, PMAT, Metaphase I, Anaphase I, Telophase I, Crossing over, End w/2 cells still diploid

In what two ways does meiosis produce genetic variation?

Crossing over and independent assortment

Simmularites

Share simular stages, produce new cells, starts with a diploid parent cell