Title: AP Biology Review
1AP Biology Review
2Reproductive BarriersLeading to Speciation
- Prezygotic Barriers
- Postzygotic Barriers
- Habitat Isolation
- Temporal Isolation
- Behavioral Isolation
- Mating
- Mechanical Isolation
- Gametic Isolation
- Fertilization
- Reduced Hybrid viability
- Reduced Hybrid fertility
- Hybrid breakdown
3Lab 8Population Genetics and Evolution
- You used the class as a sample group to look at
the relationship between violating a
Hardy-Weinberg condition and the changes in
allele frequency. - Evolution here is defined as change in allelic
frequency. - Hardy and Weinberg independently suggested a way
to view evolution as changes in frequency of
alleles in a population. - If certain conditions are met the allele and
genotype frequencies will remain constant from
generation to generation. They are - Hardy-Weinberg Conditions
- Large Population
- Random Mating
- No Mutation
- No immigration or emigration
- No selection
4Hardy Weinbergp2 2pq q2 1
- Total of all alleles p q 1
- p A allele, q a allele
- p2 AA homozygote (dominant)
- pq Aa heterozygote
- q2 aa homozygote ( recessive)
54 of a sheep population has black wool, 96
white. If black wool is recessive what of the
population is heterozygous?
- q2.04
- q v.04 .2
- 1-q p
- 1-.2 .8
- So q .2 p.8
- Substitute in 2pq
- 2 (.8) (.2) .32 or 32
64 of a sheep population has black wool, 96
white. If black wool is recessive what of the
population is heterozygous?
- What of the population is homozygous for white
wool? - Substitute in for p2
- .82 .64 64
7A Few Genetics Terms
- Autosomal traits- on non-sex chromosomes.
- Sex-linked-genes on sex chromosome
- sex-influenced- trait that appears differently in
different sexes. On autosomes. - Sex-limited- characteristic appearing exclusively
in one sex but whose gene is usually on an
autosome. - Allele- form a trait can take.
- Test cross-cross between an unknown genotype with
a pure recessive for the trait (you always know
the genotype from the phenotype). - Linked genes- on same chromosome. Wont show
classic mendelian ratio. - Crossing over- exchange between homologous
chromosomes.
8A Few more genetics terms
- Interaction between alleles
- 1. Complete dominance- one allele appears
phenotypically if present. - 2. Incomplete dominance- The phenotype is
intermediate between the dominant and recessive
form, often due to ½ the product of the gene
being produced. - 3. Codominance- both alleles are fully expressed.
- 4. Multiple alleles- more than two alleles for a
gene are found within the population (not within
an individual). - 5. Epistasis- one gene alters the effect on
another gene. - 6. Polygenic inheritance- many genes contribute
to a phenotype. - 7. Pleiotrophy- one gene can effect several
phenotypic traits. - 8. Environmental Influence- where the genotype
and environment interact to determine the final
phenotype.
9Lab 7 Genetics of drosophila
- You collected data from a fruit fly cross and
analyzed results, - Drosophila have 4 pairs of chromosomes.
- They show complete metamorphosis-egg, larvae,
pupa, adults. - We looked at three types of crosses
- monohybrid-single contrasting pair of
characteristics. - Dihybrids-two pairs of contrasting traits are
considered simultaneously. - Sex-linked-mutant characteristic associated with
the X chromosome. (white eyes). - Pgeneration-pure parents
- F1 offspring of the P generation
- F2 offspring of the F1 generation
10Lab 7 Genetics of drosophila-analysis
- You counted e.g. 67 red eyed flies
- 33 sepia flies
- You would expect 31 ratio
- 100 x ¾ 75 (100 is the total number of flies)
- 100 x ¼ 25
- Chi- square- statistic used to see if your
results are close enough to the expected results
to be acceptable (significant) - X2 ? (o-e)2 o observed
- e e expected
11Lab 7 Genetics of drosophila-analysis
- X2 (67-75)2 (33-25)2 3.41
- 75 25
- Determine degrees of freedom
- Categories 1 So 2-1 1
If probability from the Chi-Square table is
greater than your value you may accept your null
hypothesis- There is no statistically
significant difference between your observed and
expected data.
12Genetics question
- A male fruit fly with red eyes and long wings was
mated with a female with purple eyes and
vestigial wings. All of the offspring in the
F1generation had red eyes and long wings. - These F1 flies were test crossed with purple-
eyed vestigial winged flies. Their offspring,
the F2 generation, appeared as indicated below - 125 red eyed, long winged
- 124 purple eyed, vestigial winged
- 18 purple eyed, long winged
- 16 red eyed, vestigial winged
13Genetics question
- Knowns Purple and vestigial are recessive- The
F1 generation in a dihybrid cross shows the
dominant trait because all of the organisms are
hybrid. This was a special cross, it was a test
cross in the F1 generation. - P cross was ppvv x ppvv
- F1 generation was ppvv (all red long)
- F1 test cross was ppvv x ppvv
- p purple v vestigial
- P wild red v wild long
14Genetics question
pv pv pv pv
pv ppvv ppvv ppvv ppvv
Red, Long Red, Vestig. Purple Long PurpleVestig.
This cross does not show a typical 9331 ratio
of a dihybrid cross. Nor does it show the
1111 ratio predicted from the Punnett Square
(see above). The number of parental types seen
in the F2 is large and indicates there is linkage
of the two traits. They are on the same
chromosome. Crossing over is responsible for the
few recombinants.
15Lab 4Plant Pigment and Photosynthesis
- Part I You separated plant pigments using
chromatography. - Part II You measured the rate of photosynthesis
is isolated chloroplasts. - We used a blue dye, DPIP. When it is reduced
(OIL RIG) it goes from blue to clear. - Electrons usually reduce NADP but reduce reduce
DPIP instead in this setup. - You measured transmittance of light using the
cholorimeter. - You compared rate of
- Unboiled in the dark (no light to excite the
electrons) - Unboiled in the light
- Boiled in the light ( chloroplast membranes were
disrupted) - No Chloroplasts (Control)
16Plants
- Meristems-generate cells throughout the plants
life. - Apical- extend roots and shoots (Primary Growth)
- Lateral- add girth (secondary growth)
- Transport tissues
- Xylem-water and minerals
- Phloem- carry sugar
- Xylem is made of
- Tracheids- long thin
- Vessel elements- wider, shorter
- Both are dead at functional maturity
- Movement of water from roots to leaves occurs by
- Bulk-Flow- the movement of fluid driven by a
pressure difference at opposite ends of a
conduit. - The pressure difference is generated at the leaf
end by transpirational pull ( lower pressure) at
the leaf end. - Water pulled tight against the cell walls in the
air spaces of the leaf cause the negative
pressure which draws water up xylem.
17PlantsAlternation of Generations
Sporophyte
Meiosis
Zygote
Sporophyte Generation (2n)
Gametophyte Generation (n)
Spore
? ?
Fertilization
Gametes
Gametophyte
18Major Branches of the Animal Kingdom
Protostomes Mollusks, Annelids and
Arthropods -Spiral Cleavage (cell divisions are
along a diagonal line) -Determinate (cell fate is
established early) Mouth forms from
blastopore Schizocoelus (solid masses of mesoderm
form coelom)
Coelomate Have a true coelom- a body cavity lined
with tissue of mesodermal origin
Bilateria (bilateral symmetry) Cephalization 3
germ layers
Porifera Sponges
- Deuterostomes
- Echinoderms and Chordates
- -Radial Cleavage (cell divisions line up with the
original cell divisions). - Indeterminate (allows for identical twins!)
- anus forms from blastophore
- Enterocoelous (outpockets of the archenteron form
the coelom)
Animals
Pseudocoelomatea Rotifer-Coelom not completely
lined by mesoderm
Subkingdom Eumetazoa
Radiata-Cnidarians Radial Symmetry
Acoelomate No cavity between the gut and the body
wall. Flatworm Platyhelminthes
19Germ Layers and Their Derivatives
- There are three germ layers
- Ectoderm
- Endoderm
- Mesoderm
20Germ Layers and Their Derivatives
- Ectoderm
- Epidermis and associated parts hair and nails
- Lens and retina of the eye
- Enamel of teeth
- Nerve Cells
- Medulla of the adrenal gland
- Inner Ear
21Germ Layers and Their Derivatives
- Endoderm
- Inner lining of
- Alimentary Canal
- Lungs
- Middle ear and eustachian tube
- Gallbladder
- Lung tubes
- Urethra
- Urinary Bladder
- Bulk of
- Thyroid
- Parathyroids
- Thymus (where immune cells mature)
- Pancreas
- Liver
- Prostate Gland
22Germ Layers and Their Derivatives
- Mesoderm
- Dermis of skin
- Connective tissue
- Cartilage
- Bone
- Lymphoid Tissue
- Blood
- Blood Vessels
- Heart
- Skeletal Muscles
- Smooth Muscles
- Kidneys
- Testes
- Ovary
- Cortex of the Adrenal Gland
A partial list for all germ layers.
23Operons
- In Prokaryotes
- Region of a chromosome where a set of genes are
transcribed at one time. - Allows all of the enzymes needed for a pathway to
be present at once. - Two Types
- Inducible are usually off but can be turned on.
Like the lac operon. - Repressible are usually on but can be turned off.
Like the trp operon.
24Muscle Contraction
- Sliding Filament Theory of Contraction
- Thick (myosin) and thin (actin) myofilaments
slide past one another shortening the muscle. - Control- Ca from the sarcoplasmic reticulum
floods the muscle fiber when depolarized by a
nervous impulse. The Ca moves the regulatory
protein (tropomyosin) out of the way, by binding
to troponin, allowing the cross bridges to form. - Functional unit Sarcomere
- Muscle fibers can be slow-twitch (slow to
fatigue) or fast twitch ( quick source of power) - Cardiac muscle-interconnected
- Smooth muscle-lack myofilament organization, but
still use sliding filament theory.
25Circulatory System
- Open or closed (kept in vessels, all
vertebrates). - No separate blood and lymph in the open system
(like insects). Fluid is not called blood. It is
hemolymph. - Blood vessels carry blood
- Plasma-carries ions, proteins, hormones and
metabolites. - Formed elements of the blood are erythrocytes
(red blood cells)-carry O2 - Leukocytes (white blood cells)-fight infection.
- Platelets-cell fragment function in blood
clotting. - Blood Vessels
- Arteries carry blood away from the heart, Veins
to, - Lymphatic System returns interstitial fluid to
the bloodstream. Moves through lymph nodes where
many cells of the immune system search for
antigens
26Evolution of the Heart
- Fish-
- Single loop- to the gills, body, gills
- Two chambered heart
- Amphibians and reptiles
- Double loop
- Three chambered heart
- Mammals and birds
- Double loop
- Four chambered heart
- Better for active animals-keep oxygenated and
deoxygenated blood separate,
27Lab 11aAnimal Behavior
- You looked at the response of organisms to
environmental variables. - Ethology is animal behavior
- Behavior may be
- Learned
- Innate (inherited)
- Orientation Behaviors- help animal find the most
favored environment. - Taxis-toward or away from a stimulus
- Kinesis- random movement-not orienting toward a
stimulus. - Agonistic behavior
- Animal response that is aggressive or submissive.
- Mating behavior
- Complex behaviors that promote continuing the
species.
28Lab 11BReproductive Behavior in Fruit Flies
- Mating follows a distinct behavioral pattern, a
courtship pattern. - 1. Orientation
- 2. Male Song (wing vibration)
- 3. Licking of the female genitalia
- 4. Attempted copulation
- 5. Copulation
- 6. Rejection (extrusion of ovipositor)
29Blood Clotting
- Vessel damaged, muscle cause constriction.
- Platelets adhere, form a plug
- Platelets pinch off from large cells in the bone
marrow called megakaryocytes - Enzymatic reactions below are triggered by the
platelets adhering. - Prothrombin is converted to thrombin
- Fibrinogen is converted to fibrin which
reinforces the clot the platelets are forming.