Unit 5 cell reproduction

Interphase

A period of a cell's life before division

G1 Phase

Cell growth, normal activities

S phase

DNA replication

G2 phase

Preparation for cell division (double-check new chromosomes and create new organelles)

Mitosis

Cell divides into two genetically identical daughter cells

Prophase

Nucleus dissolves, chromatin condenses into chromosomes, centrioles migrate to ends of cell

Metaphase

Chromosomes line up down middle of cell, spindle fibers attach

Anaphase

Spindle fibers pull apart chromosomes and their copies to the opposite ends of the cell

Telophase

New nuclei start to form

Cytokinesis

Cytoplasm pinches off and two distinct cells form

Centromere

The structure that holds chromosomes to their copies, also where the spindle fibers attach

Sister Chromatids

Two identical copies of the same chromosome formed by DNA replication

Chromatin

Uncoiled DNA. This is what DNA looks like when the cell is not dividing

Centrioles

A cell organelle that develops spindle fibers used in cell division

Spindle fibers

The structures that pull apart chromosomes during cell division

Daughter cells

The cells formed as a result of mitosis

Chromosomes

Tightly coiled bundles of DNA

Meiosis

Forms haploid gametes and creates genetic diversity through processes such as crossing over

Prophase I

Crossing over switches genetic info and leads to genetic diversity

Metaphase I

Homologous chromosomes line up side-by-side

Anaphase I

Homologous chromosomes split apart

Telophase I

New nuclei appear

Prophase II

Chromosomes condense, no crossing over this time

Metaphase II

Sister chromatids line up down center of cell

Anaphase II

Sister chromatids divide

Telophase II

New nuclei appear

Homologous chromosomes

Two pieces of DNA within a diploid organism which carry the same genes. One is from mom, and one is from dad.

Diploid

Contains a full set of DNA

Haploid

Contains half a set of DNA. Sex cells (for example, eggs and sperm)

Gamete

A cell with half a set of genetic material, can combine with another gamete of the opposite sex.

Fertilization

When two haploid gametes come together to form a zygote, a fertilized cell with a full set of genetic material.

Haploid number

If an organism's diploid number is 18, its haploid number is 9.