14 billion years old

from the red-shift of the light from distant stars, moving away from us at rapid speeds

4.6 billion years old, it is thought to be in its third incarnation after several supernovas

this is determined by potassium40/argon40 ration from meteorites and lunar rocks

cant use the rock on earth because it is continualy recycling (reabsorption and erosion)

3.5-2.5 billion years ago

beginnings of life, prokaryotic

cyanobacteria gradually increased O2 by photosynthesis (oxygen is toxic to amino acids and other organic compound formation but allows larger organisms to from)

oxygen in upper atmosphere created ozone blocking UV

mitocondria probably formed

2.5-.5 billion years ago

dominated by prokaryotes and protists

Eukaryotes (mitocondra in cells) started 2 billion years ago

Lyn Margulis theory: mitochondria symbiosis with aerobic bacteria

multicellular forms started 1 billion years ago Neoproterozoic (1st fossils, divergence of animals, plants, and fungi)

550 Million years ago to present

Paleozoic Era, Mesoaoic Era, Cenozoic Era

550-250 million years ago (Pangea)

part of Phanerozoic Eon-all major phyla present

starting with cambrian (period 550mya) expolsion of animals and fossils (first major) and ending with the Permian extinction (last of several waves) of most animals 95% marine species-meteorite

small soft bodied metazoans in Burgess shales (fossils)

Laurasia and Gndwanaland fuse into Pangeae

evolved in two directions, onto land and greater complexity

250-66 million years ago

part of the Phanerozoic Eon

Triassic (seas repopulate, mass extinction), Jurassic (mass extinction), cretaceous periods (meteor)

dominated by dinosaurs (warm blooded) and ending with the cretaceous Perion and extinction of the dinosaurs 150 milliion years of dino rule

therapsids 200mya (mammals derived)

archosaurs (birds derived from)

Archaeoptyerynx-fossils of birds 150 mya

66 million years ago-present

Part of the Paleozoic Era

 Mammals
break up of pangaea

includes Pleitocene period (1.5 million years ago) of major recent speciation

climate cooler and drier

cycical isce ages, 100,000 years each

currently undergoing major extinction by humans

Ernest Mayr

Biological Species Concept

the evolutonary formation of new biological species, usually by the division of a single species into two or more genetically distinct ones

Only considered two species when cannot in breed any longer

gene flow between the two stops

mutation: random (human blood group frequencies vary geographically)

genetic drift: small populations, founder effect

Natural selection: especially sexual selection

occures due to...Premating isolation

differences in mating behavior and physiology (pheremones)

Presence of mechanical isolation (spawning time in sea urhins) and Gamete isolation (shape of insect exoskeletons or inability to form zygotes)

Post-mating isolation: mules, ligers

2 species are physically isolated for a long period of time

founder events: Hawaiian islands (Honeycreepers)

populations remain in physical proximity but do not mate

(due to behavioral changes)

adjuacent populations evolve into distinct species while maintiaingin contact along a common border

(perhaps secondary, after allopatry has led to divergence)

homozygosity

cheetah, has almost no variation in genotype this is due to a bottleneck that occured thousands of years ago in the cheetah species

in the absence of disrupting factors, the frequencies of p and q will stay the same forever.NO NO NO

(mutations, assortive mating, selection (allels equally fit), genetic drift)

(p and q are the two alleles for a gene at any locus in a somatic cell)

random with respect to evolution

only source of new alleles

shuffled through sexual reproduction

mostly eliminated

Natural: eliminating deleterious mutations

Stabilizing:extreme phenotypes eliminated, results in homogeneous phenotypes

only if extremes are deleterious (birth weights in humans)

subset of natural selection

rationale: females produce less eggs

(invest alot of energy in every offspring, want best sire)

Males produce many sperm (wnat to impregnate as many females as possible, compete for females, appearence and performance)

all this results in sexual dimorphism

each allele recognized

ABO blood types

Rh proteins are NH3 channels in kidney, blood cells, multiple genes

Rh+ and Rh-

females with Rh- need to ge treatment with Rh- antibodies after every pregnancy to destroy any RH+ cells from the baby before her body makes some of her own and prevent maternal immune system from becoming sensitized

when this occures there is no treatment

leads to replacement of one allele by another

Insecticide resistance in insects

use to be the real stuff of evolutionary change but now is moslty due to man

for the mutant phenotype

because this is often how they are discovered

galactosemia-mutation of gene encoding an enzyme involvedin transformation of lactose to glucose via galactose

homozygous recessive (both parents heterozygouse 1 in 4 chance)

also: albinism, cystic fibrosis , phenylketonuria (to tyrosin amino acid metabolism is disrupted and so accumlate poisounus phenylalanine derivatieves), beta-thalassemia (hemoglobin chain is defective), Tay-sachs disease (fatal brain disease), sickle-cell anemia

appear later in life

50/50 % chance of inheritance

Marfan's syndrome: Abe lincon possible -tall and thin

Huntington's disorder: neural degeneration

genes on the x chromosome, males especially affected

affected females are rare because most effected males do not live long enought to reproduce

hemophilia A-loss of blood clotting factor VIII (queen victoria)

Duchenne muscular dystrophy, red-green color blindness

insertion, deletion, dupliation,

inversion-segment turned around

translocation- segment moved to another chromosome often in reciprocal exchange(childhood cancer)

these two are leading cause of cancer

trisomy-21 or Down's syndrome

cause by spontaneous non-disjunction (non-segregation during meiosis) of the two #21 chromosomes in one parent

mothers after 45 have increased risk of giving it to thier kids

this is the only loss or addition of an autosome that can survive

xxy-kinefelter syndrome

xxx-metafemale

YO-not viable

XO- turner syndrome

xyy-father non-disjunction

chorionic-villi sampling

amniocentesis later in pregnancy

embryonic screening or preimplantation diagnosis can now test 1 cell of an 8 cell embryo before IVF to prevent homozygous recessive disorders

Direct to Consumer or DTC testing now available and cheaper but not FDA approved so called entertainment "23andMe"

idea that gemmules of Darwin carry characteristics from somatic cells to the gonads to be passed on the the next generation 

if you are strong (body build), your children will be strong

used numerical and statistical approach

pea plants, 7 characters

pea color, pea shape, flower color and position, plant height.

when genes for two characters are on the same chromosome

if you get one from mom you get both etc

monohybrid-one trait monitored (2 phenotypes and 1:2:1 genotype)

dihybred-two traits monitored (3 phenotypes and 9:3:3:1 genotype)

produce as many haploid sperms as possible

about 150 million every day

posterior, grows from brain, neural tissue, doesnt synthesize hormones

ADH:kidneys-water/salt regulation, Oxytocin-uterine,milk, pitocin (snthetic oxytocin

Anterior, ACTH (corticotropin)-adrenal gland, thyrotropin-thyroid gland, FSH-ovary, LH-ovary, Prolactin-breast, somatotropin-STH (growth)-general

light sensitive

secretes melatonin in absense of light regulating circadian rhythms

synthesizes and secretes thyroxine

requires iodine-deficiency results in goiter

Many effects on homeostasis: temp, metabolism

Deficiency: weight gain, sluggishness, congenitally: metal retardation

cortex-cortisol: lipid hormone, suppresses inflammation

Medulla secretes adrenalin/epinephrine: fight or flight, peptide hormone

exocrine and...

endocrine: islets: alpha cells secrete glucagon, beta cells secrete insulin

Diabetes type I-beta cells disfunction (juvenile-injections)

Type II- tissues dont respond (adult-diet, exercise, weight loss)

assembled from cholesterol, lipid soluble readily crosses membrane

bind to cellular receptor proteins then enter nucleus (receptor-hormone complex binds to DNA) switches gene on or off

assembled from amino acids

water soluble

3-180 aa in length

bind to receptor proteins in cell/plasma membrane, activate membrane bound enzymes and may trigger 2nd messangers (cAMP most common)

oxygen moves into internal environment and CO2 moves out

gases diffuse across membrane, driven by differing pressure gradients of gases on opposite sides of the cell membrane

O2=21% of moleules in air

CO2=.04%

• the cell surface must be moist (gasses will only diffuse in solution)
• cell layers must be thin
• O2 and CO2 concentrations must differ across the membrane

lungs inelastic, and highly vascularized, air moves through lungs into expanding air sacs (accessory air sacs that contract on exhalation forcing air back through lungs doubling the amount of oxygen taken up...

flow-through system

• Nose
  
• pharynx
• larynx
• trachea
• bronchi:bifurcatioon of the trachea
  
• bronchioli: branch till fine then end in alveoli
  
• alveoli: very close to capilaries, exchange occures
  

4 peptides, each containing a heme group with iron at its center

affinity for O2 when high partial pressure (in pulmonary capillaries)

lower affinity when in tissues where low partial pressure

molecules binding strongly to hemoglobin because they make it unavailable to the weak bond that O2 would form,

CO and Nitrates (nitrites)

only 20% carboxyhemoglobin can cause death

medulla oblongata-sets main rhythm

pons fine tune it

when brain detects H+ breathing is increased

O2+e-+O2-

superoxide which is a free radical and will bind with anything

superoxide dimutase combinds H+ with O2- creating H2O2 or hydrogen peroxide

Catalase then breaks it down into water and O2 but requires vitamins and/or anti-oxidants

only monomers!

fatty acids

amino acids

simple sugars

components of nucleoties (bases and ribose)

based on sugars

C, H and O

broke down in mouth

built up from amino acids

contain N

digested in stomach

build up for tiglycerides

broke down in small intestine

sugar/phosphate backbone

bases

broke down in stomach

amylase: break carbohydrates into disaccharides

disaccharidase: convert disaccharides to monosaccharides, simple sugars

chitin and cellulose can only be digested by rumans

proteins and nucleic acids digested here

pepsin cleaves proteins into small peptides

digests fats

trypsin, chymotrypsin and carboxy, amino-peptidases cleave single amino acids from the acid and amino ends respectivly of peptides

digested in stomach

sugar phosphate backbone cut by low pH

continues in small intestine Endo/exo nucleases contingue degradation

bonds cleaved between bases and sugars

digested in small intestine

(fats not water soluble)

liver secretes bile into gall bladder, derived from cholesterol, consits of salts of cholic acid

emulsified fats digested by lipases releasing fatty acids

mostly small intestine

duodenum primarily digestion (1st section)

jejunum primarily absorptive ( 2nd section)

lined with villi that are composed of microvilli to increase surface area

continued absorption of ions and water

appendix here

B1,2,6

B12 (missing in vegan diets)

folate or folic acid

pantothenic acid B5

biotin

c

purly toxic

lead, cadmium, mercury

may prevent birth defects and miscarriages

prevent heart attacks

potentially toxic and biproduct of the degradation of bases of nucleotides

aquatic animals excrete dilute amounts of ammonia (NH3) since they can afford to lose alot of water

terrestrial animals secrete uric acid, double ringed structure that readily forms crystals and thus require very little water

mammals excrete urea, two amino groups connected, done in kidneys-made of nephrons (discrete units of tubules and blood vessels)

fluids returning to the kidney cortex from the medulla of the kindey

absorbs sodium that was originally filtered out

also water

other chemicals are activly secreted from the blood: drugs

urine

collected in ureter

stored in urinary bladder

released via urethra

kidney

in mean time dialysis machine is used 3x a week for several hours each time: to remove toxic solutes