Test 2 (Mitosis, Plasma Membrane) Flashcards
What is mitosis?
Mitosis is the dividing, and thus, reproduction of cells
What are the stages of mitosis?
- Prophase
- Metaphase
- Anaphase
- Telophase
- Cytokinesis
What are the stages of the cell cycle?
- Interphase (G1, S, G2)
- Mitosis (prophase, metaphase, anaphase, telophase, cytokinesis)
What happens during interphase?
- Growth 1: Cell carries out metabolism and regular activities
- Synthesis: The cell replicates all of the DNA in the nucleus
- Growth 2: The cell prepares for mitosis
What occurs at each step of mitosis?
- Prophase: DNA condenses around histone proteins, creates chromosomes, called supercoiling
- Metaphase: Chromosomes line up at the equator of the cell
- Anaphase: Chromatids are pulled to the poles of the cell
- Telophase: Nuclear envelope comes back, DNA uncoils, cleavage furrow forms
- Cytokinesis: Cell divides along cleavage furrow
What is diploid number?
The fully paired sets of chromosomes in a cell, represented as 2n
What is haploid number?
Single set of unpaired chromosomes in a cell, represented as n
What is equational division?
The same amount of DNA is in each of the daughter cells as the parent cell had
What is the mitotic index?
Ratio between number of cells in mitosis and total number of cells. Found by dividing number of cells in mitosis by total number of cells obvserved
What are intrinsic proteins?
They are integral proteins. They go all the way through the membrane
What are extrinsic proteins?
They are the peripheral proteins. They are only attached to the outside of the membrane, sometimes go part way through
What is the sugar side chain used for?
It is used in cell recognition
What is cholesterol used for?
It is used to restrict the movement of the membrane. It reduces the fluidity and the permeability of the membrane
What is diffusion?
It is the passive movement of particles from a region of high concentration to a region of low concentration until equilibrium is reached
What is a hypotonic solution?
The solution has a lower solute concentration than inside the cell. This causes water to rush into the cell, which may cause the cell to burst, known as cytolysis
What is a hypertonic solution?
The solution has a higher concentration of solute than inside the cell. This causes water to rush out of the cell, which may cause the cell to shrink, known as plasmolysis
What is simple diffusion?
When substances move through the phospholipid molecules in the membrane
What is facilitated diffusion?
The cell uses channel proteins to help the substances pass through (each channel can only let in 1 substance) and the substance still goes from high to low concentration
What is a phospholipid?
Basic components of biological membranes. They are amphipathic, meaning that one side is hydrophilic, the other hydrophobic
What is active transport?
Movement of substances across the membrane using ATP. It can move substances across the concentration gradient
What is a phospholipid?
Basic components of biological membranes. They are amphipathic, meaning that one side is hydrophilic, the other hydrophobic
What is ATP?
It is made of ADP and an inorganic Phosphate molecule
What is the structure of sodium-potassium pumps?
In the centre of the pump, there is 2 bonding sites, one for the sodium, the other for the potassium. Depending on the state, the Na+ or K+ ions will be discharged into the cell, and the other will bind
What is a potassium channel?
Used in neurons, they allow K+ ions to exit the cell. They have a ball and chain they will open and close the channel
