Cell Cycle and Mitosis Review Flashcards
What are the two reasons why cells have to divide?
The cell has more trouble moving necessary items across the cell membrane
The larger a cell becomes the more demands the cell places on its DNA (DNA overload)
Explain what DNA overload means
Larger cell makes greater demands on unavailable genetic material and resources. in time the cell would no longer be able to serve the increasing needs of the growing cell. The cell needs to divide a duplicate copy of DNA between two cells.
Explain what happens to the surface and volume ratio as a cell enlarges.
The bigger the cell, the smaller the ratio, less effetiona.
In a living cell, what part of the cell represents surface area and which part of the cell represents volume
Surface Area - Cell membrane
Volume - Cytoplasm
What are some adaptations that cells have developed that allow for a greater surface area volume ratio?
Divide; Slow down metabolism: Change shape(become long and flat)
Cell division occurs in two main stages. What are they?
Mitosis (a division of the nucleus) and cytokinesis (a division of the cytoplasm).
What is the G0 stage? Give 3 examples of cells that, once matured in the G1 phase, enter the G0 stage indefinitely.
For cells that never divide (resting stage). Examples: sperm, egg, red blood, neurons, cardiac.
Cells spend most of their lifetime in what stage? What 3 phases of the cell cycle does this include?
In the interphase. This includes G1, S, and G2 phase.
What are the four stages of mitosis, in order?
Prophase, Metaphase, Anaphase, Telophase
Differentiate between chromatin and chromosomes in terms of:
Structure Tin - Loosely coiled Some - Tightly coiled
Appearance Tin - Cursive L Some - Looks like an X
Organization Tin - Sloppy (Unorganized) Some - Organized
Presence in cell Tin - Found in interphase Some - Seen only in cell division
Visualization on a microscope Tin - Smaller (Need electron microscope) Some - Larger (Light microscope)
Briefly explain how six feet of DNA is packed into the nucleus of every cell of our body! Use the terms: histone, nucleosome, chromatin, loosely coiled, supercoiled
DNA wraps around proteins called histones which further bundles intp nucleosomes this is called chromatin. Its loosely coiled until time of dividing then super coiled.
How many chromosomes are found in human body cells? How many chromosomes are found in human sex cells (egg and sperm)?
46 chromosomes in the human body, 23 from each parent. (23 in sperm, 23 in egg)
What is the name of the proteins that regulate the cell cycle
Cyclin
Define cancer
a disease caused by an uncontrabble division of abnormal cells in a part of the body
What are tumors and what are the 2 types of tumors
A mass of cells dividing rapidly, Benign and malignant
