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Unit 4 AP Biology (partial) Cheat Sheet (DRAFT) by

Condense information for a Unit 4 test Chapters 13 to 14 from the Biology -- sixth edition by Raven and Robinson

This is a draft cheat sheet. It is a work in progress and is not finished yet.

Reduction Division

Sexual Reprod­uction = Genetic Diversity = GOOD
Pierre and Joseph

Reduction Division

Sexual Reprod­uction
= Genetic Diversity = GOOD
Pierre and Joseph
gametes (egg & sperm) each contained 2 chromo­somes; somatic (nonre­pro­duc­tive) contained 4 chromo­somes (most cells)
Fertil­ization (Van Beneden)
= syngamy = fusion of gametes
Reduction Division
producing cells with half the number of chromo­somes = meiosis
Sexual Life Cycle
meiosis + fertil­ization = sexual reprod­uct­ion­diploid cells
diploid cells=2 sets of chromo­somes
haploid cells= one set of chromo­somes (23 through eggs & 23 through sperm1)
Somatic Tissues
post fertil­iza­tion= zygote divides by mitosis
plant cells=­haploid cells divide by mitosis
Germ Line Tissues
In animals= cells set aside to undergo meiosis & produce gametes
gamete­-pr­rod­ucing
Synapsis 2
aligning of homologous chromo­som­es(­hom­olo­gues)
Homologous Recomb­ination 2
Crossing over= small segment excahnages
1 This does not mean 1/2 mom, 1/2 dad
2 Special features of Meiosis (PEQ)

Unique Features of Meiosis (PEQ)

Synapsis
aligning of homologous chromo­­so­m­e­s(­­hom­­ol­o­gues)
Homologous Recomb­ination
genetic exchange between homologous chromo­somes
Crossing over= small segment excahnages
=Genetic diversity
Reduction Division
Chromo­somes do not replicate beteween the 2 nuclear divisions

Prophase 1

Leptotene
Chromo­somes condensed tightly
Zygotene
  
synaptomal complex
Pachytene
Diplotene
Diakinesis
 

Early Ideas of Heredity

Classical Assumption 1: Constancy of Species
heredity occurss within species
Classical Assumption 2: Direct Transm­ission of Traits
traits are transm­itted directly
Koelreuter
carried out hybrid­ization of plant species
Classical Assump­tions Fail
traits can be 'masked' and reappear in one generation (contr­adicts theory of direct transm­ission)
traits­-se­gre­gation of altern­ative forms of character
TA Knight and Peas
did not quantify or count their results
Early geneti­cists demons­trated that some forms of an inherited character (1) can disappear in one generation only to appear unchanged in future genera­tions; (2) segregate among the offspring of a cross; and (3) are more likely to be repres­ented than their altern­atives.

Mendel and the Pea

Why Peas?
large variety of pea
large # of true breeding varieties
sexual organs enclosed within flower
LUCKY
Pea plants only have 2 genes for each trait
Mendel
Father of Genetics
F1 generation (1st filial)
F2 generation (2nd filial)
hidden in F1 may have reappeared in F2
Punnet Squares
predicts offspring possib­ilities
capital letters- dominant
lowercase letters- recessive
Mendel- Model of heredity
No blending effect
Law of Segreg­ati­on(­Men­del's 1st Law of Heredity)
Mendel's second law of heredity: Indepe­ndent assortment
dihybrids= indivi­duals eheter­ozygous for both genes
genes located on different chromo­somes assort indepe­ndently indepe­ndently during meiosis
gened ilocated on different chromosmes assort indepe­ndently
continuous variation
greater # of genes that influence character
the more continuous the expected distri­bution of versions of trait character
pleiot­ropic effects
individual allele will have more than one effect on the phenotype
on gene effects many traits in marked contrast to polyge­my(many genes effect one trait)
Lack of complete dominance (codom­incnce)
ability to see hetero­zygous zygote
EX: red dominant over white but when together as hetero­zygous the recessive trait is not allowing it to be fully red (red+w­hit­e=pink)

Blood Groups and Rh Factors (PEQ)

ABO blood groups
Landst­einer blood groups
Type A
add only galact­osamine
Either IAIA homozy­gotes or IAi hetero­zygotes
Type B
add only galactose
Either IBIB homozygous or IBIb hetero­zygous
Type AB
add both sugars (galac­tos­amine and galactose)
IAIB hetero­zygous
Universal recipient
Type O
add neither sugar
are ii homozygous
Universal donor
incorrect transf­usion
agglut­ina­te=­cause cells to clump
Rh Blood group antigens
named after rhesus monkies
Rh-pos­itive = Rh cell surface marker
Rh-neg­ative = lack the Rh cell surface marker
Rh negative
detect Rh surface antigens as
Rh negative mother births Rh positive child= build antibodies which secon time around could kill baby (eryth­rob­las­tosis fetalis)

Inheri­tance

pedigree
maps the flow of traits;s doinance and recess­iveness
sexlinked traits (sex linkage)
trait determined by a gene on the x-chro­mosome
whatever is on the x shows since there is no combative gene or compet­ition on y
some traits tend to stay within races
EX: sickle cell anemia= African americans
chromo­somal theory of inheri­tance
similar chomosomes paired with one another during meiosis
problem with chromo­somal theory
why does number of characters that assort often greaetly exceed the number of chromo­somes pairs the organism posesses

Genetic Recomb­ination

crossing over
exchange of chromosome arms
form of recobi­nation
Genetic Map
results of crosses that can be put together to measure distance between genes in terms of frequesncy recomb­ination
A map unit
centim­organ
3 point cross
cross involving 3 linked genes
Human genome Project
sequence the entire human genome
 

Epistasis

Epistasis
one gene can interfere with the expression of another gene
Eample Lab REtrievers
Gene: EE or Ee = dark pigmme­ntation ee=no pigmen­tation
second gene: E_B_ = black fur E_bb= brown fur
eebb = brown bigment on brown nose of yellow lab eeB_ = black pigment on the nose of yellow labs