ANFS345 exam 4

How does the body obtain energy?

In chemical form, from food

How does body use energy?

Biosynthesis, maintenance, generation of external work

How is energy lost?

heat

Small animals and energy

-eat more relative to their body size
-large SA to V ratio
-high metabolism
-lose energy fast

large animals and energy

- don't eat as much
- smaller SA to V ratio
-slower metabolism

glycolosis

breaks down glucose into 2 molecules of pyruvate and 2 NET ATP

Does glycolysis require oxygen?

No, it is anaerobic

krebs cycle

-starts with pyruvic acid from glycolysis
-makes 5 ATP (most of any process)
-turns the pyruvate into acetyl coenzyme A

Does the Krebs cycle need oxygen?

yes, aerobic

Where does the Krebs cycle occur?

mitochondria

How many ATP made from glycolysis and krebs combined?

27

electron transport chain

for every 10 protons moved - 2.5 ATP made

How many protons does complex 1 move?

4 protons

How many protons does complex 2 move?

none

How many protons does complex 3 move?

4 protons

How many protons does complex 4 move?

2 protons

oxidative phosphorylation

Gradient formed by the electron transport chain acts as an energy store
- ATP synthase moves protons to "complex 5" which makes heat
-useful for hibernation

More protons in intercellular space=

=more ATP can be made

Lactic acid

-Made if only glycolysis is performed

-makes muscles hurt

-can be turned back to pyruvic acid to continue whole krebs and electron transport chain process

Sprinters vs. Marathoners

-sprinters use lots of glycogen in muscles
-marathon runner needs fatty acids

oxygen at start vs end of exercise

- at the start of exercise, lag of O2 demand before body realizes it needs to kick in
- at end of exercise, body has excess O2 until it realizes its no longer necessary

Energy storage for performing work

In order from using first to last
1. Creatine (ATP storage) for energy
2. ATP from glycolosis (anerobic)
3. ATP from Krebs cycle (aerobic)
4. ATP from fat

Things required for egg and sperm to meet

- environmental cues
-developed reproductive organs
-acquisition of resources
-attraction of mates
-copulation (intercourse)

Things required for successful offspring

-development of zygote
-provisioning of offspring
-evasion of predators
-parental time
-no environment stress

mammal sex determination

XX- female
XY- male
50/50 shot
males determine the sex

Birds and reptiles sex determination

use Z and W
50/50 shot
mom determines sex

turtle sex determination

temperature
hot=female
cold=male

A lot of lizards are only females in the species

True, they can clone themselves

Ant sex determination

fertilized egg= female
non fertilized egg= male (have no father)
called a haploid-diploid system

Reproduction up North (in poles)

Peak of reproduction is at spring
-so they are mature by fall when the cold weather becomes harsh

reproduction in tropics

Can effectively reproduce at anytime

dipause

A pause in development for them to catch up on weather

Examples of dipause

-silkworms have dipause in winter within their eggs to hatch in the spring
-antartic fur seals have dipause right after birth in summer/fall

male and females have same external genitalia for a while in the womb

True, males change right before birth

female reproductive system

2 ovaries- connected to oviducts- leads to uterus- cervix- then vagina

Where doe sperm interact in females

in oviduct, then embryo attaches to the uterus

corpus luteum

secretes hormones for early pregnancy (progesterone)

How does the female cycle work?

-Follicles mature from primary to secondary, then oocyte gets released (ovulation)
- the area around it forms a mature Corpus leuteum
-if not fertilized, the CL will stop secreting and move away
-This causes the uterine lining to shed since no pregnancy occured

FSH (follicle stimulating hormone)

stimulates follicular phase

LH (luteinizing hormone)

surge triggers ovulation
-can test LH levels to see when you will ovulate

Progesterone

helps support pregnancy
-secreted by CL

Estrogen

stimulates development of follicles

Inhibin

inhibits secretion of FSH (inhibits follicular phase)
-causes follicles to rupture for ovulation

why does the uterine lining shed?

Lots of blood vessels are formed in uterus in case there is an embryo to provide nutrients for after ovulation (secretory phase)
-so it sheds if nothing attaches
-called menstral phase

proliferate phase

-right after menstral phase

-corelates to follicles devolping

-has high estrogen and low progesterone

HPG axis

controls reproductive system

How is estrogen secreted?

-hypothalamus secretes GnRH
-anterior pituitary secretes LH and FASH
-LH stimulates Theca cells (outer most part of follicle) to produce androgens
-androgens move inside to granulosa cells (second layer of follicle)
-aromatase (enzyme) turns androgens into estrogen
-estrogen is secreted into blood and helps follicle mature

How is the LH surge triggered?

Cervix sends info to make GnRH
-GrNH produces the LH surge at copulation

male reproductive system

testi- vas derens- semical vesicle- prostate glans-penis

testis

produces sperm

semical vesicle and prostate gland

-produce semen
-gives nutrients to sperm to survive

Scrotum

makes sure sperm doesn't overheat

Leydig cells

produce testosterone in seminiferous tubule

parts of sperm

-head is called acrosome- helps penetrate oocyte
-has mitochondria in the middle to help tail swim
-tail

Testosterone

-surge before birth if embryo is male
-surge after birth for final touches
-in low phase from ages 1-10ish when testes drop
-spikes at puberty which beings sperm production
-stays high forever on

teste size

-smaller testes tend to mate for life with single female

-multi-male mating= larger testes (bc more surface area for more testosterone to make more sperm and offspring)

fertiliation steps

1. oocyte is in oviduct as sperm arrives

2. sperm head binds to specific receptors on zona pellucida (outside of oocyte)

3. sperm interacts with oocyte body which doesn't let any other sperm in

4. sperm releases its contents into oocyte cytoplasm aka DNA

*space between zona pellucida and oocyte is call perivitelline space

when is spike of hCG

after fertilization
-only seen if uterus attaches

CL then produces high levels of progesterone and estrogen during pregnancy after hCG spike

when do estrogen, progesterone, and hCG all drop?

after birth
-this can lead to lack of care from the mother

How does a woman's body give birth?

-cervix and uterus get stretched before birth which sends signals to the hypothalamus
-The hypothalamus tells posterior pituitary to release oxytocin into blood
-oxytocin tells uterus to contract
-also produces prostaglandins which help uterus contract
- a positive feedback loop keeps calling for more oxytocin

marsupials

-have 3 vaginas
-can keep one baby in uterus and another in pouch
-can pause pregancy
-ex: kangaroos

Monotremes

mammals that lay eggs (platypus)
-1 hole for everything
-lay eggs, but still use milk from mom's body

placental mammals

-nourish their young with milk from nipples and placenta

Mom's energy needs to be highest at

weaning (transition from milk to food)

- this is because baby's body is smaller earlier on so less energy/milk is needed until it is big enough to have real food

Milk production: suckling activates...

CNS which allows for lower dopamine and higher TRH hormones
-this causes prolactin to secrete from anterior pit. and oxytocin from posterior pit.

prolactin

allows epithelial cells to make milk

oxytocin

allows the milk to be ejected

ionotropic transduction

ions go through channels to activate signal

Metabotrophic transduction

ligate binds to receptor for signals

Mechanoreceptors

respond to touch, pressure, vibration, stretch, and itch
ionotropic

vestibular receptors

balance, body position and movement; ionotropic

Osmoreceptors

osmotic pressure
ionotropic

auditory recpetors

sound
ionotropic

Thermoreceptors

heating and cooling
ionotropic

Electroreceptors

detect electrical fields
ionotropic

salty and sour taste chemorecptors

ionotropic

sweet, bitter, umami

metabotropic

olfacotry receptors

smell
chemicals from a distance
metabotropic

Photoreceptors

light
metabotropic

Magnetoreceptors

detect magnetic fields
unknown transduction

sensory recepetors

- go from sensors to CNS without interacting with each other to make signals as fast as possible
-each corralates with a part of the brain
- when the sensors detect above a threshold, the body realizes a change in environment
-frequency and strength of the signal matters

free nerve ending

paint, itch, temp

merkel disc

touch and pressure

meissner corpuscle

touch

Ruffini endings

pressure

Pacinian corpuscles

vibration

tonic receptors

-merkel disc and ruffini ending
-impulses continue during long stimulus

phasic receptors

-meissner corpuscle
- impulses happen in change of level of intensity

Extremely phasic receptor

-pacinian corpuscle
- neglible signal outputs

Taste depends on

smell

each part of tongue tastes a different flavor

FALSE all parts of tongue can detect all 5 tastes

ear

converts sound energy to neural signals, then brain processes the info

cochlea

-filled with saltwater fluids
-inner ear
-frequencies detected on all different parts of cochlea

eardrum and middle ear

convert movement of eardrum to pressure waves in cochlea fluid

basliar membrane

has hairs on outside of cochlea that translates frequencies to nerves

high vs low frequency

-high frequency sounds=more intense and happen over shorter distance
-low frequency sounds= stretched out over longer distance and reach ear first

Pathway of sound through the ear

pinna-> ear canal-> eardrum-> tympanic membrane> malleus, incus, and stapes> cochlea-> hair cells (basial membrane) -> brain

range for animal hearing

14- 200,000
but each has its own specific range
ex: bats hear highest frequency at 7,000-200,000
ex: elephants hear lowest range at 14-12,000

Tympanal organs

hearing organ in insects
-membrane with air sacs and sensory nerves

first sense you are born with

smell