Lab 2 - Mitosis And Movement Across Cell Membrane Flashcards
What is the Cell Cycle?
Cell reproduction/division that is regulated by a series of events
What is Interphase?
Time during cell growth where the cell grows in size, carries out normal metabolic activities and prepares for cell division
What are the phases of interphase?
- G1
- S
- G2
What is cell division?
The series of events that lead to the production of two identical cells referred to as daughter cells from one original parent cell
What is the G1 phase?
The cell grows and conducts normal cellular functions
What occurs during the S phase?
DNA is replicated or “synthesized”
What occurs during G2 phase?
The cell prepares for cell division by duplicating organelles and other cytoplasmic materials.
What is the G0 phase? Name an example of a cell
Known as the non-dividing stage
- Liver and muscle cells
Name the two series that happen at the M phase?
- mitosis
- cytokinesis
What is the centromere?
The region of a chromosome to which the microtubules of the spindle attach, via the kinetochore, during cell division.
What is a homologous chromosome?
Are a pair of chromosomes that have the same genes at the same loci, but possibly different alleles
Name the four major phases of Mitosis.
- Prophase
- Metaphase
- Anaphase
- Telophase
Name 5 things that occur during prophase.
- Chromatin fibres condense into visible chromosomes
- The nucleolus disappears
- The nuclear envelope breaks down
- The centrioles are pushed to opposite poles by lengthening microtubules
- Spindle fibres form and asters are visible around centrioles
What occurs during metaphase? (1)
- The microtubules of the spindle fibres align the centromeres of each of each pair of chromatids at the metaphase plate.
Name two things that occur during Anaphase?
- The centromeres split and the chromatids separate and move towards opposite poles
- The chromatids are now called chromosomes and appears V - shaped
Name four things that occur during Telophase.
- Chromosomes are at the poles and begin to uncoil into chromatin
- The nuclear envelope reforms around the chromatin
- The nucleoli reappear
- The spindle breaks down
What is Cytokinesis?
Cytokinesis begins in late anaphase, with a slight indent in the plasma membrane called the cleavage furrow. It is the process of microfilaments contracting to pull the plasma membrane inward. This marks the completion of cell division into two daughter cells
True or False:
Daughter cells are genetically different then the parent cell after mitosis
False: they are genetically the same as the parent cell after mitosis
How many chromosomes are present during anaphase?
2 chromosomes are present during anaphase
What is one possible reason that chromatin fibres condense before dividing?
Because it is easier to separate the chromatin when it is condensed rather then when it is able to roam freely
What is Blastula?
An embryonic phase of development that occurs shortly after fertilization, this is when the embryo is undergoing rapid cell division.
What is the plasma membrane?
A physical barrier that surrounds each cell separating it from the environment and regulating which substances pass into and out of the cell.
The plasma membrane specifically is a semipermeable phospholipid bilayer.
Name the two types of transport that can occur across the membrane.
- Passive transport.
2. Active transport
What is Brownian Motion?
States that all molecules have kinetic energy and are constantly colliding with adjacent molecules.
What is passive process?
Molecules that move along their concentration gradients requiring not energy for the movement of the molecules
Name three passive processes.
- Filtration
- Diffusion
- Osmosis
What is active process?
Requires the use of energy (adenosine triphosphate = ATP), water-soluble substances are moved against their concentration or electrical gradient
Name two forms of active process.
- Active transport
2. Vesicular transport
What is diffusion?
Movement of molecules from an area of higher concentration to an area of lower concentration of a certain molecule, the driving force behind diffusion is kinetic energy.
What is Osmosis?
A type of simple diffusion where water moves through a selectively permeable membrane from an area of higher water concentration to an area of lower water concentration
What is a solute?
Is any substance that dissolves in another
What is a solution?
The result of dissolved solute becomes a solution
What is a solvent?
The substance that the solute dissolves in
What does it mean to be hypotonic?
A solution with a lower concentration of solute is said to be hypotonic to the solution with the higher concentration of solute
What does it mean to be hypertonic?
The solutions with the higher concentration of solute is said to be hypertonic to the solution with a lower concentration of solute.
What does it mean to be isotonic?
Two solutions with equal concentrations are said to be isotonic
What does hemolysis refer to?
When a Red blood cell (erythrocytes) is placed in a hypotonic solution, water enters the cell, eventually causing the cell to burst
What does it mean when a cell crenates?
When a Red Blood Cell (erythrocytes) is placed in a hypertonic solution, water will leave the cytosol and enter the solution outside the cell. The cell appears crenated aka shrivelled with spiked edges
What do you use as a negative control for starch?
Iodine
