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Haploid
One set of chromosomes
Diploid
two sets of chromosomes
Telomere
noncoding sequence at the end of chromosomes
Centromere
location on a chromosome where sister chromatids contact

general point of mitotic spindle
Kinetochore
associated with cetromere, formed on top

attach to microtubules in mitosis to separate chromatids
Somatic Cell
normal cell that is not a germ cell
Germ Cell
cell responsible in reproduction, can be fertilized
True breeding
inbred organisms that produces offspring of same genotype/phenotype
homozygous
Cross fertilize
fertilzation of different species/varieities
Dominant
expressed genetic factor
Recessive
latent genetic factor, only expressed if homozygous dominant
Gene
DNA sequence that codes for RNA
Allele
different forms of a gene
Homozygous
2 identical copies of an allele
Heterozygous
2 different copies of an allele
Genotype
allelic constitution
Phenotype
physical characteristics of a gene
Parental
starting/founding strains
Filial
offspring of parent strains
Segregate
separation of alleles
Prokaryotic cell
structure
-generally very small
-can posess cell walls, functions vary
-rudimentary flagella

internal components
-no MBO
-DNA is free in cytoplasm
-posess ribosomes from prot synthesis
-also have plasmids, small circular DNA

genetic info storage
-one circular chromosome
-one origin of replication
-circular plasmids
Eukaryotic cell
structure
-generally larger than prokaryotes
-animal cells have no cell walls
-more advanced flagella

internal components
-several MBO with different fxns
-large nucleus
-some cells have vacuoles
-mitochondria or chloroplasts

genetic info storage
-many linear chromosomes with multiple origins of replication
Mitosis
produces 2 identical daughter cells
PMAT+cytokinesis
Meiosis
produces 4 nonidentical daughter cells

prophase
1. leptonema- chromosomes condense
2. zygonema- homologous chromosomes synapse
3. pachynema- tetrads exchange genetic info "crossing over"
4. diplonema- homologs begin to separate except at chiasmata
5. diakinesis- chromosomes' kinetochores attach to mitotic spindle fibers to migrate to metaphase plate.
What is the synaptonemal complex?
Why is it important to crossing over?
-2 homologous chromosomes pair during prophase 1, zygonema. They form contact points, called chiasmata. At this point, the two homologues are called tetrads. During pachynema, the genetic information is exchanged between the homologes in a process called crossing over.

-Crossing over enables new recominant gametes to be formed. This creates genetic variation in a population. A recominant gamete may give rise to a protein taht is favored greatly by the environment. Eventually evolution will occur as it selects for individuals with this recominant DNA
Model organisms
-e. coli
-d. melanogaster
-c. elegans
-s. cerivisae
-mus musculus

enable us to study the principles and processes of genetics

can be monitored and reproduced easily

short generation spans

genetic analysis
Monohybrid cross
Dihybrid cross
Trihybrid cross
Mendels principles
dominance- 1 allele may conceal presence of another

segregation- 2 allele segregate from each other during gamete formation

independent assortment- alleles of diffrent genes segregate independently (unless they are linked)
Probability eqns
Probability that ther will be 3 boys and 4 girls

7!    (1/2)3 (1/2)4
3!4!
Pedigrees
What is genetic counseling?
-help people understand and adapt to the medical, psychological, familial implications of genetic contribution to disease
-educate about inheritance/testing
-promote informed choices and adaptation to risk
-interpretation of family and medical histories to assess the chance of disease
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