Chapter 11 quiz Flashcards
What happens in the G1 phase?
Preps for cell division. Increases in size, synthesizes duplicate organelles and organic molecules that are needed later on
What happens in the S phase?
Synthesizes a complete copy of DNA after chromosomes are duplicated
What happens in the G2?
Cell gets larger again. Synthesizes the organelles and proteins, and reorganizes genetic material for mitosis
What happens in the M phase?
Divides the cell into 2 daughter cells
What are multipotent cells?
Cells in adults that can replace the cells in tissues they are found in
What is apoptosis?
Programmed cell death
What is a tumor that is non cancerous?
A benign tumor
What is the first phase of mitosis and what happens?
Prophase: Genetic material condenses and chromosomes become visible. Spindle starts to form
What is the second phase of mitosis and what happens?
Metaphase: Duplicated chromosomes line up in the center of the cell, spindle fibers connect the centromeres to the poles of the spindle so the cell can separate the sister chromatids
What is the third phase of mitosis and what happens?
Anaphase- Chromosomes move to opposite ends of the cell. Chromosomes are completely separated into 2 groups
What is the fourth phase of mitosis and what happens?
Telophase: Chromosomes start to spread out and tangle back into chromatin. Nuclear membrane forms around each cluster and nucleolus slowly becomes visible in each daughter nucleus
Advantages of sexual reproduction?
Genetic diversity
Disadvantages of sexual reproduction?
A much longer process and organism must find another parent
Advantages of asexual reproduction?
Very fast process, only one parent needed, produces a lot more offspring
Disadvantages of asexual reproduction?
Offspring are genetically identical to parent (no genetic diversity)
What are the characteristics of a cancer cell?
Cancer cells can form tumors that metasize, unspecialized, and have defective genes
What structure is found in prokaryotic but not eukaryotic cells?
One circular DNA chromosome in the cytoplasm (prokaryotic chromosome)
Why do cells divide?
Replace damaged cells, produce more cells while organism is growing, make sure a cell doesn’t get too big
What happens if cells get too large?
-It would become harder to move materials in and out of the cells, which would cause blockage of materials
-DNA wouldn’t be able to keep up so it makes a copy and divides
How many chromosomes do humans have?
46
DNA tightly bound to proteins
histones
What is chromatin?
The complex of dna and protein
What is binary fission?
Form of asexual reproduction, used by prokaryotes, 2 DNA molecules attach to different regions of cell and cell pinches inward to divide
What stages make up interphase?
G1, S, G2
What is cytokenisis?
Completes cell division process. Cell membrane drawn inward until cytoplasm is pinch into 2 equal parts
When do most cells stop dividing?
When they touch each other
What do internal regulatory proteins do?
Respond to events inside cell. Act as checkpoints that allow the cell cycle to proceed once certain events have taken place
What are growth factors?
Stimulate the growth and division of cells. Very important during embryonic development + wound healing
What is the embryo stage?
what animals and plants pass through as an adult organism is produced. Cells become more and more different from each other and specialized for particular functions
What is differentiation?
the process of cells becoming many different types of cells
Totipotent
zygote is able to do everything, to develope into any type of cell
What does a embryo turn into after 4 days
A blastocyst: a hollow ball of cells with cluster of cells inside known as inner cell mass
Pluripotent cells
inner cells that can develop into any boy cell type
