Week 7 (exam 2) Flashcards
What are the 2 basic processes of the cell life cycle or cell cycle and explain them
1) cell division- single cell splitting into 2 identical daughter cells
2) Apoptosis- natural cellular death
What is mitosis?
Division of nucleus and the chromosomes the nucleus contains
Used to mean cell division
What is cytokinesis?
When cell splits into daughter cells
What are the 4 events of the cell cycle?
1) M phase or Mitotic
2) G1
3) S
4) G2
What is the M phase or Mitotic of the cell cycle?
Cell division
Daughter cells double numbers of organelles (mitochondria, nucleus, etc) to bring back to correct number and accumulate materials needed
What is the G1 phase of the dell cycle?
To copy DNA
What cells are too large and complex, stop at G1 phase and are described as perpetual (G0)?
Neurons (nerve cells) and skeletal muscle cells
What is perpetual mean?
Go on forever
What is the S phase of the cell cycle?
DNA is copied
Not visible under microscope
Semiconservative synthesis of DNA
What is semiconservative synthesis of DNA mean?
Duplicate of DNA
Genetically identical cells are called what?
Daughter cells Or Clones
Before mitosis or m phase finishes what happens?
Cytokinesis
What stages of the events in a cell cycle are called interphase and why?
G1, S and G2
Not much visibly seen under microscope
What helps the process of mitosis or m phase?
Chemical signals inside and outside the cell
What is a checkpoint?
Built in the cell cycle to stop cycle if something that needed to be accomplished is not
Cycle has to happen in orderly fashion and not too quickly
What does the checkpoint in the middle of the M phase do?
If chromosomes are not properly aligned the checkpoint holds everything until the chromosomes are properly aligned
What does the checkpoint in phase G1 do?
Cell examines DNA to make sure it is not damaged
If there is damage (mutations) the cell attempts to repair to DNA if cannot be repaired cell initiates apoptosis
What is the G2 phase of the fell cycle?
Getting ready for another cell division (M phase)
Gathering material
Use microtubules so you have to accumulate tubulin protein
What is p53?
Protein responsible for checkpoint in G1
What happens if p53 is unable to be produced?
Without p53 checkpoint in G1 disappears
That means cycle will continue even if DNA isn’t copied correctly
How rumors appear in people because a genetic mutation appears
What does prophase do?
Beginning of prophase chromosome condense together and starts to look like big butterfly, little butterfly or house fly
Nuclear envelopes break down
Chromosomes move to middle of cell
Centrioles (2) move polar ways and create spindle
What is polar?
Centrioles move in opposite directions on the side of the cell
What happens during the metaphase stage?
The chromosomes align along imaginary midline of the cell (metaphase plate)
Centrioles are now on the opposite sides of the cell
Chromosomes attach to spindle by centromeres (dot in chromosome)
Spindle passes through line of chromosomes
What is the metaphase plate in metaphase?
Imaginary midline between the cell
What happens during the anaphase stage?
Chromosome break in half and follow microtubulles rapidly moving to opposite sides
What are the daughter cells called when split in half and move in opposite direction?
Daughter chromosome
What happens during the telophase stage?
Begins: all motion stops
Chromosomes reach destination (opposite sides of cells) (polar)
Cytokinesis happens
(Can see in microscope)
When cell splits each one gets same stuff
What is the cytokinesis cleavage furrow?
The dent between cell that deepens as cell splits
What are the 4 basic kinds of tissues?
1) Epithelium
2) connective tissue (CT)
3) muscle
4) nerve
What is epithelium tissue?
Forms membranes and glands
Membranes:
- Protect deeper structure in the body and/ or interface between the body and outside world
- Covering
- Ex: interface in lungs
What are the layers of epithelium and explain
1) simple- one layer
2) stratified- multiple layers
3) pseudostratified- one layer but looks like many
What does the checkpoint at the end of phase G2 do?
Stops cycle until DNA finishes copying itself
What are the stages of M phase or Mitosis?
1) Prophase
2) Metaphase
3) Anaphase
4) Telophase
PMAT
What are the shapes of epithelium tissue and explain
1) squamous- rectangle
2) cuboidal- square shape
3) columnar- night greater than width (rectangle standing up)
What is the apical surface?
Upper surface of the cell