Download Review Guide Cell Division CP

CP BIO
Ch. 10-11 Cell Division
Review Study Guide
Amatuzzi
10.1 Mitosis and Asexual Reproduction
a. one parent cell, genetically identical daughter cells
- for growth, maintenance, repair, reproduction in simple organisms
1. prokaryotes – binary fission
2. eukaryotes – chromosomes organized and distributed equally
b. Rate of division – some tissue often, others rarely; uncontrolled (cancer)
12.2 DNA Molecule – helix, nucleotide, bases (names), base pairs
12.3 DNA Replication – DNA copying: double helix opens, free nucleotides A-T, C-G
- each original strand is template for a new strand  two identical molecules,
- each has one original strand and one new strand
10.2 The Process of Cell Division
A) Chromosomes = DNA + histone proteins = nucleosomes  make chromatin
a. chromatin – DNA in non-dividing cell
b. in dividing cell: copied DNA condenses into sister chromatids , joined at
centromere
B) The Cell Cycle
a. Interphase G1 S (replication) G2
b. M Phase mitosis – nucleus divides; cytokinesis - cytoplasm divides
1. prophase – - spindle forms, chromatin condenses, nuclear membrane
breaks apart, centrioles move apart
2. metaphase – chromosomes at equator of cell, attach to spindle
3. anaphase – sister chromatids separate & move to opposite poles
4. telophase – two new nuclei form, chromosomes unpack
c. Cytokinesis – cleavage furrow in animal cells; cell plate in plants
C) Cell Differentiation – stem cells, unspecialized
D) Asexual Reproduction – same traits, quick, many offspring, no gene variety
- in simple animals: budding, regeneration
Plants: runners, bulbs, cuttings
E) Regulating the Cell Cycle - chemical signals, growth factors, cyclins,
contact with nearby cells, programmed death
F) Cancer - uncontrolled growth, benign tumors, malignant, metastatic, melanoma
11.4 Meiosis and Sexual Reproduction
Two parents – each gives genes  new gene combination in offspring
Two sets of homologous chromosomes – have genes for the same traits
A) Diploid and haploid cells
a. Diploid – two sets of chromosomes (2n) –one set from each parent
i. In somatic (body) cells
b. Haploid – one set of chromosomes (n)
i. In sex cells, gametes – egg and sperm
B) Meiosis – for making gametes
a. two cell divisions, reduces chromosome number by half
b. Interphase - DNA replicates
c. Meiosis I – divides homologous pairs of chromosomes
i. Prophase I – pairs match up (synapsis), attach at centromeres
a. Crossing over – homologous chromatids exchange pieces
b. Increases genetic variation, chromatids vary slightly
ii. Metaphase I – pairs line up on equator
iii. Anaphase I – pairs separate still two copies – sister chromatids
iv. Telophase I – two haploid nuclei form; cytokinesis
d. Meiosis II – sister chromatids separate; cytokinesis again
 four haploid daughter cells
C) Making Sperm and Egg
a. 2n parent cell  four haploid sperm
b. 2n parent cell  one haploid ovum + 3 polar bodies (die)
D) Fertilization: egg + sperm  zygote n + n  2n
a. zygote divides by mitosis to make more cells
14.2 Problems in Meiosis
A) nondisjunction – pairs or chromatids do not separate correctly
- wrong number in daughter cells
a) trisomy – three copies of one chromosome
- Down’s Syndrome is trisomy #21
b) nondisjunction of sex chromosomes: Klinefelter XXY, Turner XO
B) Chromosome mutations – pieces lost, added, misplaced
a) addition, deletion, inversion, translocation
C) Karyotype – picture of paired, sized chromosomes
a) autosomes – numbers 1-22
b) sex chromosomes – X and Y