Chapters 8 And 9 Flashcards
Why are new cells needed
Growth and cellular and sexual reproduction
Three steps to prokaryotic reproduction
Replication (DNA)
Elongation
Binary Fission (cell divides)
Chromosomes are made up of
Chromatin
What are chromatin
DNA wrapped protein bundles
Coiled and folded chromatin is considered
Condensed
Sections of DNA that are coded for one thing are called
Genes
How many pairs of chromosomes do human cells have
23
How many chromosomes do humans have
46
Chromosome pairs are called
Homologous pairs
After replication 2 chromatids link at
Centromere
XY chromosome makes what gamete
Sperm
XX chromosome makes which gamete
Egg cell
Cell cycle in Eukaryotes has three stages
Interphase
Mitosis
Cytokinesis
three phases of interphase
G1
S
G2
G1 phase of interphase is
First Gap
90% of time is spend in this phase
Cell grows
S phase of interphase is
Synthesis
Replication of DNA
G2 phase of interphase
Second gap
Mitochondria replicate
Microtubules made
Chromosomes start condensing
Division of genetic material is called
Mitosis
4 phases of mitosis
Prophase preparation
Metaphase middle
Anaphase apart
Telophase tidy
Nucleus disappears
Spindles appear
DNA finishes condensing
Prophase
What happens during prophase
Nucleolus disappears
Spindles appear
DNA finishes condensing
Chromosomes line up
Attach to spindles
Metaphase
What happens during metaphase
Chromosomes line up
Attach to spindles
Chromatids separate
Microtubules drag to poles
Anaphase
What happens during anaphase
Chromosome pairs separate
Microtubules drag then to poles
Nucleus reforms
Chromosomes uncoil
Telophase
What happens during telophase
Nucleus reforms
Chromosomes uncoil
What happens during cytokinesis
Cell finish separating
Cleavage furrow formed in animal
Cell plate formed plant
3 checkpoints in cell cycle
Between G1 and S
The S and G2
Then between metaphase and anaphase
Cancer is
Cell growth and division out of control
Proto-oncogenes
Promotes division
Tumor suppressor genes
Turn off cell division
Asexual reproduction
Organisms copy themselves
Uses mitosis only
Sexual reproduction
Formation of new organism by combining DNA of 2 parents
Diploid cells have ____copies of every chromosome
2
Haploid cells have ____copies of every chromosome
1
Meiosis
Cell division to reduce amount of genetic material
Cell division to reduce amount of genetic material
Meiosis
Prophase 1
Nucleus disappears
Chromosomes finish condensing
Chromosomes pair up (synapsis)
Crossing over occurs
Nucleus disappears
Chromosomes finish condensing
Chromosomes pair up (synapsis)
Crossing over occurs
Prophase I
Metaphase I
Spindles form
Homologous pairs line up(random)
Spindles form
Homologous pairs line up(random)
Independent assortment
Metaphase I
Anaphase I
Homologues pull apart
Homologues pull apart
Anaphase I
Telophase I
Clustering at ends of cell
Prophase II
New spindles form
Metaphase II
Chromosomes line up in center
Anaphase II
Chromatids separate and pulled to poles
