Mitosis- Cell Division Flashcards
What is a chromosome?
Compacted DNA that looks like a small X.
How many chromosomes come from your father and mother?
You receive 23 chromosomes from your mother and 23 from your father.
What is Cell Division?
The making of two new identical cells used only by eukaryotes.
What is a diploid?
Two complete sets of chromosomes.
What is a haploid?
One complete set of chromosomes.
What occurs in Mitosis?
A cell duplicates its DNA and nucleus to then divide into two identical daughter cells.
If there are 46 chromosomes in a human. How many will be left after Mitosis?
46 chromosomes
What is DNA?
Genetic material
What is Chromatin?
Genetic material attached to proteins that look like spaghetti.
What are Chromosomes?
Condensed and compacted chromatin. (DNA)
What are Chromatids?
Split in half Chromosomes.
What are the three main steps of the Cell Cycle?
Interphase, Mitosis, Cytokinesis
What are the four phases of Mitosis?
Prophase, Metaphase, Anaphase, Telophase
A cell spends most of its time in which stage?
Interphase
What occurs in Interphase?
G1: cell grows, organelles double in number; cell does its job
S (DNA synthesis) DNA is copied
G2: More growth
What occurs in Prophase?
- The nucleus begins to divide
- Poles start appearing and begin to move to the opposite sides of the cell
- Spindle fibers form between the poles
- Chromosomes become visible
- The nuclear membrane breaks down
- Chromatids attach to an area called the centromere
- Spindle fibers extend from the centrioles
What occurs in Metaphase?
- Chromatids (or pairs of chromosomes) attach to the spindle fibers
- Chromosomes meet in the middle
What occurs in Telophase?
- Two new nuclei form
- Chromosomes appear as chromatin (threads rather than rods)
- Mitosis ends. This is the end of nuclear cell division but cells are not completely divided yet.
What is Apoptosis?
- Programmed cell death
- Cell produces self destructive enzymes
- Example - Webbing between fingers in fetus
Metastasize
When cancer spreads to other parts of the body
What is Cancer?
- Uncontrolled division of abnormal cells in a part of the body
- Cancer cells divide constantly and form clumps called tumors
What is a benign tumor?
A tumor that stays in the same place and can be removed.
What is a malignant tumor?
A tumor that breaks apart (Metastasize) and can form tumors in other parts of the body.
