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Chapter 12: Cell Cycle
 The function of mitosis
o What does it do?: produces somatic cells
 How many, and what types of cells are produced?
o 2 daughter cells from 1 parent cell
 Somatic cells vs. gametes
o Where are they found?: somatic cells in the body, gametes in sex organs
o How do they differ in chromosome number?: somatic: 46, gametes: 23
 Chromatids vs. chromosomes
o How do they differ?: 2 chromatids make up 1 chromosome
o When does a chromatid become a chromosome?: as soon as the
chromatids divide, they’re chromosomes
 Centromere vs. centrosome
o Where are they found?: centromere is the center connection piece of a
chromosome (1 per chromosome); centrosomes are the small parts of cells
where microtubules originate during mitosis
 Mitosis vs. Cytokinesis
o How do they differ?: mitosis is division of genetic material, cytokinesis is
division of cell
o Where do they take place?: in the cell
 Sister chromatids vs. nonsister chromatids
o How do they differ?: sister chromatids are attached to make up a
chromosome; nonsister chromatids aren’t connected
 phases of cell cycle
o G0 is a no growth stage; G1 and G2 are growth stages, S (synthesis) stage
is when replication of chromosomes occurs
 benign vs. malignant tumors
o How do they differ?: benign tumors are cancerous but are confined to one
area; malignant tumors invade surrounding tissues
 kinetochore vs. aster
o Where are they found and what do they do?: the kinetochore is the place
where spindle fibers attach during division to pull the chromosomes apart,
kinetochores are found in the cell during mitosis; the aster forms around
the centrosome during mitosis, the asters move to opposite ends of the cell
and help prepare for mitotic spindle formation
Chapter 13: Meiosis
 Function of meiosis
o What does it do?: produces gametes through 2 consecutive cell divisions
o How many/what types of cells are produced?: 4 daughter cells are
produced that are all gametes (sperm or eggs)
 Asexual vs. sexual reproduction
o How do they differ in their end product?: sexual reproduction leads to
more diverse offspring
 Animal vs. plant life cycles
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o How do the stages differ in terms of being haploid/diploid, single
cell/multicellular?: gametes are haploid, somatic cells are diploid
Autosomes vs. sex chromosomes
o How many are found in a somatic cell?: 44 autosomes, 2 sex
chromosomes
o How many are found in a gamete?: 22 autosomes, 1 sex chromosome
Diploid vs. haploid
o diploid (2n) has 2 sets of chromosomes, haploid (1n) has 1 set of
chromosomes
Homologous vs. recombinant chromosomes
o How do they differ?: homologous chromosomes orient at the metaphase
plate, they line up next to each other at the metaphase plate during mitosis;
recombinant chromosomes are produced during crossing over
possible combinations of daughter cells
o ex. 2n=8, so n=4. Formula for calculating possible combinations is 2n. So,
24=2 x 2 x 2 x 2, or 16
Crossing over, locus, chiasmata, synapsis
o crossing over: occurs during prophase of meiosis, homologous
chromosomes share information
o locus: specific location of a gene on a chromosome
o chiasmata: junction between two homologous chromosomes
o synapsis: pairing of homologous chromosomes during meiosis
Chapter 14: Mendel and the Gene Idea
 P vs. F1 vs. F2 generations
o P= true-breeding parent generation, F1=first familial (offspring)
generation, F2=second set of offspring from F1 mating
 Dominant vs. recessive
o What does it mean to be either?: one dominant allele causes the trait to be
expressed; 2 recessive alleles must be present for a recessive trait to be
expressed
 genes vs. alleles
o What are they and how do they differ?: alleles are alternative versions of
genes
 homozygous vs. heterozygous
o What does it mean to be either in terms of having dominant or recessive
alleles?: homozygous means that there are 2 dominant or 2 recessive
alleles for a trait (ex. for the trait of blue eyes, which is a recessive trait,
homozygous dominant is BB and homozygous recessive is bb);
heterozygous means that one of each allele is present (Bb)
o Can you use a simple Punnett square to determine the outcome?: put one
parent across the top, the other across the side, and fill in the blanks 
 phenotype vs. genotype
o phenotype is visible or observable characteristics or traits
o genotypes is actual genetic makeup
 monohybrid vs. dihybrid crosses
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o How do they differ in the number of characters and traits?: monohybrid
crosses examine 1 (2 characters) trait, dihybrid crosses examine 2 traits (4
characters)
complete dominance vs. incomplete dominance
o How do they differ in F1 phenotypes?
o How do they differ in F2 phenotypes?
3:1 vs. 1:2:1 vs 9:3:3:1 phenotypic ratios
o How do they differ in the types of hybrid crosses and the types of
dominance?: 3:1 ratios occur from a Aa Aa cross with complete
dominance. 1:2:1 ratios occur from Aa Aa crosses with incomplete
dominance. 9:3:3:1 ratios come from dihybrid crosses.
Testcross, pleiotropy, epistasis
o What are they/what do they do?
 testcross: used to determine genotype of an individual with a
dominant phenotype by crossing with a known genotype (recessive
phenotype)
 pleiotropy: a single gene influences multiple phenotypic traits
 epistasis: one gene controls the expression of another
carriers
o How do carriers influence transmission of recessive disorders?: carriers
are heterozygous for a trait (one dominant allele, one recessive allele) and
thus are capable of passing on a disorder if they mate with someone with a
heterozygous or homozygous recessive genotype.
Chapter 15
 Wild type vs. mutant type phenotype
o How do they differ? wild type is “normal”, mutant type has a new trait not
seen in the wild type
 Linked genes vs. sex-linked genes
o How do they differ?, where are they found, how are they passed on?
linked genes are located on the same chromosome and tend to be inherited
together; sex-linked genes are any genes on sex chromosomes
 Parental type offspring vs. recombinant type offspring
o How do they differ in phenotype and genotype?: recombinant offspring
have a different phenotype and genotype than parents
 Recombination frequencies and linkage maps
o check book for examples of recombination frequencies and linkage maps
o formula for recombination frequency: (number of recombinants/total
number of offspring)x100
 Frequency of crossing over?
o What effect does gene location have on crossing over and the level of
recombination frequency?: the likelihood of crossing over is higher if
genes are farther apart
 Barr body
o inactive X chromosome in a female cell
 nondisjunction
o What happens, where does it occur, and what results? failure of
homologous chromosome pairs to separate during cell division, or failure
of sister chromatids to separate; results in aneuploidy (abnormal amount of
chromosomes)
Chapter 22: A Darwinian View of Life
 Evolution vs. descent with modification
o How can you define each?: evolution is change of a population of
organisms from one generation to the next; descent with modification is
Darwin’s personal view before “evolution” word was used
o How does microevolution differ from descent with modification?:
microevolution occurs on a smaller scale (allele frequencies in
populations)
 catastrophism vs. uniformitarianism
o How do they differ?: catastrophism was advocated by Cuvier and is the
idea that some sudden catastrophic event wiped out all organisms in the
area; uniformitarianism was advocated by Hutton and Lyell says that
scientific processes are constant over time and changes in the earth surface
result from slow and continuous actions
 natural selection vs. artificial selection
o How do they differ?: natural selection occurs by independent mate
selection while artificial selection is choosing of particular traits to breed
together
o What’s the relationship between natural selection and the environment?
natural selection brings about a match between an organism and their
environment; over time natural selection can increase the match between
an organism and their environment
 theory vs. hypothesis
o a theory is more comprehensive than a hypothesis
Chapter 23
 gene pool vs. gene flow
o How do they differ?: a gene pool is all of the genes in a population at any
given time; gene flow results from movement of fertile individuals or
gametes
 relative fitness
o What is it?: the contribution an individual makes to the gene pool of the
next generation relative to other individuals
 mutation vs. sexual recombination vs. genetic drift
o What are they and how important are they in altering allele frequencies?
 mutation: source of new alleles
 sexual recombination: most important in producing genetic
differences to make adaptations possible
 genetic drift: describes how alleles fluctuate unpredictably from
one generation to the next in SMALL populations
o What do p and q represent?
o