OCR Biology - Mammalian Physiology and Behaviour; June 2009

i was referring more to the CCK, secretin and gastrin (impulse from vagus nerve) but i guess what you wrote could be valid, minus the blood glucose maybe?

you're relating all that way too much to physics. we dont need to know stuff like moments = force x distance

What horrible essays if they have these:

Ruminant digestion (hopefully the first part will be name a ruminant)
Cow
4 stomachs - in order: Rumen, Reticulum, Omasum, Abomasum
Bacterium in rumen and reticulum produce cellulase and can digest cellulose into cellobiose and then glucose.
Glucose can be undergo anabolism to form fatty acids, can be directly absorbed in the rumen. This also produces carbon dioxide and methane.
Bacterium also use urea in cow's saliva to form proteins.
After rumen, food regurgitated and chewed again (chewing the cud) before passing down into the reticulum.
Bacterium are digested, along with any other food products, in the omasum and abomasum (abomasum most like the stomach in humans) by proteases, etc
Passes into small intestine, amino acids, glucose, any remaining fatty acids absorbed here.
Large intestine water absorption.

Absorbed amino acids are deaminated and NH2 group reformed into urea. A nitrogen cycle in the cow is formed.

Lumbar and thoracic - I doubt I could write a 6-8 mark essay on. Vertebrae on a whole maybe:
7 cervical vertebrate
12 thoracic
5 lumbar
5 sacrum
4 coccyx, fused together
Atlas vertebrate the first cervical, on top of axis, the second cervical. Atlas is up down motion of head, axis is side to side movement of head.

Vertebrae have neural spine/canal, transverse and articular (both superior - top and inferior - bottom??) and centrum.
Muscles attached to transverse processes of thoracic and lumbar - holds organs etc.
Inter-vertebral discs are cartilage, allows small movement between individual vertebrae, overall the spine is flexible.

Hmm...

what about an essay question on plasma proteins: albumin, globulin and fibrin and their functions

what about an essay question on plasma proteins: albumin, globulin and fibrin and their functions

what about an essay question on plasma proteins: albumin, globulin and fibrin and their functions

for vertebrae i would probably name cervical (5), thoraric (12), lumbar (5). I would then talk about the structure of a vertebrae in general, so centrum is load bearing part, neural arch contains a neural canal which houses the spinal cord, neural spine and trasverse processes attach to muscles, ligaments, articular processes attach to other vertebrae, between each vertebrae are intervertebral discs which act as shock absorbers and prevent friction between vertebrae.

i would then talk about the differences between lumbar and thoraric, so lumbar has a bigger centrum to withstand compressive forces, broader transverse processes and neural spine to attach to large back muscles, intervertebral notches in the lumbar allow the spinal cord to exit at points, and in the thoraric there is a much longer, thinner neural spine.

thats all i can think of from memory, i better get back to reading some more.

oh and i hate the ear's role in movement and balance.... i cant get my head around it!!

albumin: decreases w.p or blood so that water diffuses back in vessels from tissue fluid at venous end of capillaries. ( watter moves into tissue fluid at arteriole against w.p gradient end due to higher pressure).
This prevents oedema (swealling of tissue fluid if the water doesnt diffuse back out).

globulin: most globular protiens in blood e.g. immunoglobulins made by immune system. most others are made in liver have functions like transporting hormones

fibrinogen: cut, collagen fibres revielled, prothrombin-> thrombin
thrombin catalyses fibrinogen -> fibrin (which is insoluble and forms a mesh that catches platlets and red blood cells) important for stoping microorganisms getting in and blood getting out

ears role in movement + balance:

3 semicircular canals orientated in 3 planes.
they are concerned with movement of head
ampulla and cupula; when head moves fluid builds up in ampulla causing cupula to bend
action potentials in vestibular nerve to brain.


then for position of head:

utriculus and sacculus concerned with head position
utriculus for upright position
sacculus = lying down position
macula
hair cells covered in otolith layer sensitive to gravity

what are macula?

Sacs of calcium carbonate? gel which is over the hair cells. When gravity moves them, they brush over the hair cells, depolarising them, etc.

what are macula?

what are macula?

are right, so are they a bit like otoliths

is the macula at both the ampulla and the utriculus and sacculus?

Off topic but you doing CBD tomorrow morning??

How are you revising tonight?

yep im doing 2854 tomorrow.

revised all of it, except for the ******* organic reactions and conditions, and bond angles!!!

i can do the small questions, its just the long ones with QWC or conditions i always mess up, so i've never got higher than 96/120, averaging about 80/120.

today im just gonna keep rewriting every reaction and condition and just go over the revision guide one more time. ive only got 2 papers left so ill do those after.