predation

or

parasitism

interactions in which one partisipant is harmed, but the other benifits

(+/- interaction)

interactions in which two organisms use the same resorses and those resoreses are not enough to supply their combined needs

(-/- interaction )

interactions in which both participants benifit

(+/+ interaction)

interactions in which one particpant benifits but the other is uneffected

(+/0 interaction)

interactions in which one parastipant is harmed, but the other is unaffected

(-/0 interaction)

a palatable speices may mimic an unpaltable or noxious one

what is the general name for an organism that lives in the body of cells or another organism?

Is this an example of an interaction?

vriuses and or parasties

example of parastism

facultitive - prokaryotes that can shift their metablism between anerobic and aerobic operations depending on presance or abessense of O2

obligate - an anaerobic prokaryote that can not surive exposure to O2

viruses "hyjack" cell machinary to make viral copies instead of making normal protiens and nuclic acids of the cell

once cell is exausted, the cell wall is lysed (broken down), releasing hundereds or thousands of new viruses into the surrounding extra cellular space

based on mitotic division of the nucleous

produces clones of offspring that are genetically identical to the parent

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chromosomes duplicate

results is relative genetic consistancy

divding of unicellular organism

gives rise to clones

true or false

differentiated multicellular organisms can reproduce asexually

true

example: asexual spore and seed formation; budding; pathogens

a sexual production of seeds

ovules developed directly into seed; therefor seeds are gentically identical to parent

fertilzation NOT required

outgrowth of new cell from the surface of a parent cell; new cell differentiated before the buds break away from the parent

the development of unfertailized eggs

common in anthropods, only a few vertibrates

want to prevent genetic variation for a consitent quality of produce

grafting used

spontanious mutations RARLEY improve organisms ablity to adapt to its environment

but, when random accumulation of mutations in "spare" copies of genes results in the production of new and useful gene products, natrual selection tends to perpetuate transmition of mutated genes

DNA from one bacterium genetically "transforms" another type

some prokaryotes pick up genes from the environment and incorperate it into their own chromosones, becoming part of that cell's genome

viruses can carry genes picked up from one cell into another cell through repeated cycles of and cylces of infection

ex: genetic information can be transduced into bacteria using phages

true or false

there is a low risk of disease when transduction or transformation takes place in animals or humans

false

there is a HUGE risk of disease when transduction or transformtaion takes place in humans or animals

true or false

antibiodtic resistance may be passed from one bacterium to another

totipotent

each can potentially develop into an entierly new organism

when cells are seperated, will this lead to the development of gentically identical or diffenet individuals?

identical

somatic nucealr transfer (dolly the sheep)

genetically enginereed reproraming of somatic cells

variant

GENTIC DIVERSITY

conjugation

which is when bacteria draw int oclose contact with one another and DNA is transferd from one cell to another by a conjugation tube

fungia matting.

go.

pollen (male)

ovule (female)

do this

http://bcs.whfreeman.com/thelifewire8e/content/cat_010/3804001.html

sexual reproduction requries

______ to make ____, followed by the union of two ____  through fertilization.

meisos

gametes

gametes

daughter cells of meiosis are gentically the same and are n1, while daughter cells of metiosis are generally the same (appart from mutations), and are n2

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mitosis

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occurs in gonades (overies or tesites)

produced from dipload (2n) germ cells within gonade

these germ cells originally proliferate by mitosis

(females produce oogenia (2n), males produce spermatogia (2n))

oogina and speratoiga multiply further by mitoisis, producing primary ooctyes and sperocytes (2n)

meiosis reduces choromosomes to hapliod number (n)- ooctyes and sperm

male gamate- small, containing little but the haploid nucleous attached to the "tail"

female gamate- big and highly differentiated

gamets are same size

eg sea lettus

gamates are different sizes

(few large female, many small males)

increasing male gamete number increases siring sucess

reduces potential for conflict between cytoplasmic organelles in embryo (sperm doesnt contribute to cytoplasm)

larger sex cells since increasing zygote size increases survival, and larger gamets have more nutrients for zygote

to ensure that effort is put into reproduction ONLY when there is a realistic chance of success

conrtoled via hormone signalling mechanisms

luteinzing hormone (LH)

Follicle Stimulating Hormone (FSH)

estraiol (an estrogen)

progesteron ( a progesterin)

Inhibin (a peptide)

testosterone ( an adrogen)

Inhibin (a peptide)

leydig cells in the tissues between seminferous tubules produce male sex hormones

the seminferous tubules are the target of FSH (speicifically the sertoili cell) and produce inhibin

control of testies

(whole damn prosses)

simple inhibitory feedback control

at pubertiy, hypothalism GnRH release is turned on, increasing pituitary output of two gondatrophin hormones, LH and FSH

FSH stimulates Sertolli cells to produce growth factors that stimulate spermatogonia to divide

[image]

LH stimulates leydig, interstital cells of testes to produce testosterone

testorsterone acts with FSH to stimulate spermogenisis, as well as acting around the body develop male pheotype (body type)

sertoli cells respond to FSH by making inhibin, which feeds back to selectivly inhibit pituitary FSH secretion, so circulating FSH is stablilzed

testosterone acts back on the pituitary to inhibit release of LH, so circulating LH is stablized

control of overary

(whole damn thing)

reproduction begins by the hypothalic GnRH release being turned on, increasing petuitary output of two gonadotrophin hormones, LH and FSH

rise in FSH stimulates group of folicles to start devloping

as folicles develop, they both produce estradiol and inhibin which BOTH act back to inhibit FSH secretion

this produces limiiting situation in ovary, so only healthiest follicles surive the resultant "FSH starvation"

gradual rise in estradiol also results in increased synthesis, but not release of LH in petiuitary

several days of this increase in estradiol signals development of mature follicle

susstained rise in estadiol causes brain to over-ride inhibition of pituitary, cuasing intier piuitary store of LH to be suddenly released

surge of LH causes ovulation and formation of the corpus lutem from the ovulated follicle

corpus lutiem starts to secret progesterone as well as estradiol

as follecies develope, estridol stimulates uterus to grow

after ovulation, progesterone induces uterine differieniation, preparing for pregnancy

in absense of more LH, the lutinized cells in the corpus luteum die and a new cycle begins(only doesnt happen if preggo)

loss of both estradil and progesterone at end of cycle makes u bleed.

if preggers, courpus lutem wont die and will keep chugging along secreting estradiol and progesterone to keep that linning happy and healthy

FUNDIMENTALLY SIMILAR utilizing same hypothalamic and pitutary hormones

but

overary produces few, large gamates, while males produce many, small ones

and

prinicpal overian hormones are not androgens, but estadial and progesterone

JUST KNOW THESE MO FO DIAGRAMS

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[image]

[image]

desribe, in detail, the following evultionary cues of gamate production:

internal animal

seasonal animal

external plants

animals interal cues- mobile, less dependent on environment for matting

- mating needs to be cued at time when female is ovulation ie PHARAMONES

animal seasonal cues- dependent on light cycle, temp, food supply

- food, preditors and such, ensure young are born at right time

plants external cues- sessile (cant move around)

-optimum flowering time is critical stratigy

- depence on cues such as:temp, photoperiod and pollination mech

- vernalization: induction of flowering by low temps

abundent sperm and few eggs drive mating behaviour

males often initiate courshipt and fight for oprotunity to mate

sexual selection pressures: success of opsring depends on- qualilty of male genes, amount of assistnace he provides and resources he controls

female choose male based on ornamets, which leads to exaggeration

environmental- getting gamets from one place to another

-recognition mechanism

sperm-egg reconition- acrosomal process

sperm egg fusion- membrane rises around sperm head, microfilli elongate around it

environmental/behavioural

• photoperiod
• hormonal

chemical

• olfactory
• hormonal

visual/auditory

• according to darwninan behvoural rule: a juvenile is recongized by a male if he frequelntly mated with and gaurded its mother when in heat
• due to phenotupic cues (pheynotype matching)
  • smell (olfactory cue)
  • apperance (visual cues)

practived by >95% of mammalian speices

male polygamy occurs becuase female only recepitve occasionally, males sexually active always

females not receptive during pregnancy--> male-biased operantilal sex ratio

male weapons to gain access to females: males compete strongly for females

rare

females focues on producing eggs

female polygammy occurs becuase males become the limiting resouce in reproduction

about 60 fish species exhinbit males parentsal care

stronger female than male competion for mates

more pronounced female secondary traits (ie ornaments or weapons)

female-biased opertainoal sex ratio

male parental care

uniparental

(polygamous spicies)

drives the selcetion of sexual triats

males and females havae less similar sex roles, therefore seceltion pressures are differnt

biparental care

(from monogamy)

no insects, reptiles, or amphibians

3% of mammals

some fish

males and females subjected to similar selcetion pressures because they have similar roles

one mate

some animals and birds

many mates

most animals including primates