LABS Flashcards
(44 cards)
what is diabetes?
a failure of homeostatic system to regulate glucose levels.
what animals have diabetes?
humans
cats
dogs
horses
what does OGTT stand for?
oral glucose tolerance test
describe an OGTT
oral glucose tolerance test
fasting for 12h
initial blood sample
glucose drink
blood samples for 4h
what were the horse blood samples stored in?
oxalate to prevent clotting
after centrifugation of whole blood, what is each layer of the tube?
top clear layer (supernatant) = plasma.
middle layer = white cells.
bottom layer = red cells.
what are the rules when using a centrifuge?
close the tubes tightly.
BALANCE the tubes.
keeps numeric order.
lid hinges up.
put the lid on firmly.
what part of the blood sample do we test for glucose?
plasma.
what is the colour change with Benedict’s solution when testing glucose levels?
Benedict’s solution has copper ions so is blue.
glucose is a reducing sugar, able to donate electrons.
when they are heated together the solution becomes a copper oxide turning red.
no glucose = blue
increasing glucose = more red.
whats a glucometer?
uses enzyme reactions to measure blood glucose.
enzyme converts glucose to gluconic acid and H2O2 which generates an electrical signal to glucose levels.
what results indicate diabetes?
a p value of <0.05.
if the initial and the final glucose levels are significantly different that suggests the glucose homeostasis is impaired.
which horse was diabetic?
horse B
what are the three types of muscle?
skeletal
cardiac
smooth
what muscle group is under voluntary control?
skeletal
what muscle group is under involuntary control?
cardiac and smooth
describe skeletal muscles
striated muscle attached to bones of the skeleton.
control body movement.
describe cardiac muscle
striated muscle found only in the heart.
describe smooth muscle
primary muscle of the internal organs and tubes (e.g. bladder, stomach, blood vessels, visceral muscle).
influence the movement of material into, out of and within the body.
how is contraction of skeletal muscles initiated?
signals from the somatic nervous system.
troponin-tropomyosin complex covers myosin-binding sites on actin.
Ca2+ binds to troponin causing conformational change and frees myosin binding sites.
when is ATP required in muscle contraction?
maintain membrane potential.
pump calcium in SR.
enable cross-bridge cycling.
what does a cardiac muscle look like?
one nucleus only.
cells are joined end to end through structures called intercalated discs containing gap junctions.
striations are clearly visible and you can see banding patterns.
cluttered and disorganised.
what do smooth muscles look like?
lack striations.
coupled together electrically through gap junctions.
thin and streaky.
what does skeletal muscle look like?
bundles of parallel muscle fibres and each is long, thin, and multi nucleated.
big nucleus and huge myofibre.
big gaps between nucleus.
what does poikilothermic mean?
body temperature/ metabolic rate fluctuates and is affected by ambient temperature.
water fleas (daphnia) are poikilothermic.
