Temp p3

Question 1

What are the sinusoids in the liver?

Answer 1

The sinusoids in the liver are spaces between hepatocytes where blood from the hepatic artery and portal vein mixes to increase the oxygen content of blood

Question 2

What are the kupffer cells in the liver?

Answer 2

Kupffer cells in the liver are like macrophages - ingesting foreign particles to protect the liver from disease - they are found in sinusoids

Question 3

What is the canaliculi in the liver?

Answer 3

Bile is secreted from the canaliculi - the bile then drains in to ductules which transport it to the gallbladder

Question 4

What are the functions of the liver?

Answer 4

Functions of the liver:
-Carbohydrate metabolism (glucose converted into glycogen by hepatocytes)
-Deamination of excess amino acids (removal of an amino group of amino acid to be broken down into urea)
-Detoxifciation (removal of toxins, eg breaking down ethanol into ethanoate which synthesises fatty acids)

Question 5

Process of deamination as part of the orthicine cycle

Answer 5

Process of deamination as part of the orthicine cycle:
-Amino acids split into amine group (Rest of AA used in respiration)
-Amine group combines with CO2 to form urea
-Urea moves to kidneys for excretion

Question 6

Haemodialysis

Answer 6

Haemodialysis:
-Removes blood from body and pumps through a machine via a countercurrent flow
-Dialysis fluid and blood is seperated by an artificial membrane which maintains the concentration gradient
-Blood thinning agent added so to avoid blood clotting

Question 7

Peritoneal dialysis

Answer 7

Peritoneal dialysis:
Dialysis fluid is put into the body cavity so exchange occurs across their own peritoneal membrane
-Fluid is then drained and replaced

Question 8

Knee Jerk Reflex

Answer 8

knee jerk reflex:
-Leg is tapped bellow patella, causing patellar tendon to stretch (this is the stimulus)
-Initiates reflex arc - thigh extensor muscle contracts and flexor relaxes, causing the lef to kick

Question 9

Blinking reflex

Answer 9

Blinking reflex:
-Eyelids rapidly clouse in response to light and touch and sounds -> corneal reflex = touch, optical reflex = light
-Passes through relay neurone in the brain stem to a motor neurone that causes the eylids to close

Question 10

Cerebrum

Answer 10

Cerebrum = controls voluntary actions such as learning and memory

Question 11

Cerebellum

Answer 11

Cerebellum = controls unconscious functions eg balance and posture

Question 12

Medulla Oblongata

Answer 12

Medulla oblongata = autonomic controls eg BR and HR

Question 13

Hypothalamus

Answer 13

Hypothalamus = Temperature control and osmoregulation

Question 14

Pituitary gland

Answer 14

Pituitary gland = stores and releases many hormones