Unit 8: Cell Growth & Division Flashcards
Chromosome
The x-shaped structures in the nucleus of the cell that carry the directions or “recipes” for everything the cell does and makes.
Cells divide to…
- Grow
2. Replace injured cells
Gene
The individual recipe for making each and every one if your characteristics or traits.
Look like little stripes on chromosome.
Chromatin
Unorganized genetic material.
Has all of the same “recipes” that would be found on a chromosome.
Chromatid
Half of a single chromosome.
Made up if chromatin.
Held together in the centromere.
Mitosis
Part of cell cycle.
Ensures that genetic material and cells produced during CC are identical.
Interphase
Occurs IN between mitosis cycles
Growth
DNA replicates
Mitosis
The cell and genetic information is divided into TWO cells.
Prophase
Part of mitosis
PRO=NO nucleus
Spindle fibers shoot out of the centrioles.
Metaphase
Chromosomes lines up in the MIDDLE
Spindle fibers attach to centromeres
Anaphase
Chromosomes are pulled apart by spindle fibers.
After metaphase before telophase
Telophase
Two new nuclei start to form
Nuclear membrane starts to regrow
Nucleolus reappears
After anaphase
Cytokinesis
The cytoplasm pinches in and separates forming two new cells
Half the genetically material it had in prophase
Centromere
The point where chromatids form chromosomes
Prokaryotic Chromosomes
No nucleus
Usually just one, circular chromosome containing majority of DNA
Eukaryotic chromosome
Generally have more DNA than prokaryotes
Generally have multiple chromosomes
Histones
Proteins around which DNA coils
Nucleosomes
DNA/histone complexes
Packed tightly together
The cell cycle
Cell gets bigger
Cells prepare for division
Cell divides into two daughter cells which are genetically identical
Prokaryotic cell cycle
Binary fission
Can occur quickly
Asexual
Fibers form between the new chromosomes causing the cell to pinch in
Eukaryotic cell cycle
Length of cycle depends on cell
Two parts: interphase and mitosis
Four phases: G1, S, G2 and M
PMAT
Phases of mitosis Prophase Metaphase Anaphase Telophase
Spindles
Shoot out of centromeres AND centrioles
Prometaphase
The time when prophase transitions into metaphase
Begins once nuclear membrane has dissolved
What is the order of the cell cycle?
Interphase Prophase Prometaphase Metaphase Anaphase Telophase Cytokinesis
What does the cell do in cell cycle?
Grow Duplicate Grow Separate Divide
S phase
Synthesis
DNA is replicated
Twice as much DNA afterwards
Chromatin
G1
Growth
Proteins are made
Organelles are made
Chromatin
G2
Growing organelles and molecules
Chromatin
Cyclins
Protein “signal” that regulated when eukaryotic cells start and stop the cell cycles
Apoptosis
Programmed cell death
Why we have fingers and toes
Help shape tissues and structures
Benign tumor
Mass of no cancerous cells
Does not spread
Malignant tumor
Mass of cancerous cells
Life threatening
Metastasis
Malignant tumor can invade and destroy surrounding healthy tissue
Carcinogens
Known substances that cause cancer
Flow chart of cancer cells
Cancer cells do not respond to signals that regulate cell growth
Form a mass of cells called a tumor
May break loose and spread
Metastasis
Differentiation/specialization
The process of becoming specialized
Stem cells
Unspecialized cells from which differentiated cells can develop
Totipotent
Able to develop into any type of body
Pluripotent
Can develop into most, but not all, types of body cells
Blastocyst
Name for hollow ball of cells after 4 days
Inner cell mass: embryo
Out cells: tissues
Mulitpotent
Adult stem cells
More limited potential
i.e. blood, skin and bone marrow cells
