What is the correct definition of excretion?
Removal of metabolic waste
Removal of undigested food
Removal of waste via defaecation
Removal of amine groups from amino acids
Removal of your head from your shoulders
What is metabolic waste?
Undigested food
Toxic compounds produced by bacteria
Waste substances that may be toxic or are produced in excess by cells
The products of cellular reactions
Your life
Why is carbon dioxide toxic? (Choose more than one answer)
It is carried in the blood as hydrogencarbonate ions. These are toxic.
It is carried in the blood as hydrogencarbonate ions. These dissociate to form hydrogen in red blood cells which competes with oxygen and combines with haemoglobin.
It combines directly with haemoglobin and lowers its affinity for oxygen.
It is carried in the blood and lowers its pH.
It dissolves in the blood plasma and combines with water to give carbonic acid, which dissociates to give hydrogen ions, which lower the pH of the blood.
It can enter cells and inhibit respiration.
It can cause photorespiration.
What is the process of deamination?
ammonia + carbon dioxide --> urea + water
amino acid + oxygen --> keto acid + ammonia
amino acid + water --> keto acid + oxygen
amino acid + carbon dioxide --> urea + water
amino acid + carbon dioxide --> urea + oxygen
amino acid + oxygen --> keto acid + water
What is the equation for the formation of urea?
keto acid + carbon dioxide --> urea + ammonia
ammonia + oxygen --> urea + carbon dioxide
Which of these are functions of the liver? (Choose more than one answer)
Control of blood amino acid and carbon dioxide levels
Control of blood amino acid and lipid levels
Control of blood lipid and carbon dioxide levels
Synthesis of bile, plasma proteins and glucagon
Synthesis of bile, plasma proteins and cholesterol
Synthesis of bile, insulin and cholesterol
Storage of vitamins A, B and D, iron and glycogen
Storage of vitamins A, B and D, iron and bile
Storage of vitamins A, B and D, bile and glycogen
What are Kupffer cells?
Liver cells involved in metabolic processes such as protein synthesis, detoxification, etc
Specialised macrophages involved in the breakdown and recycling of red blood cells
Specialised phagocytes that engulf and ingest red blood cells
Specialised phagocytes involved in the immune system
Magic
What is used and produced in the ornithine cycle?
Used: 2 molecules of ammonia, 1 molecule carbon dioxide, 1 molecule water Produced: 2 molecules water, urea
Used: 2 molecules of ammonia, 2 molecules carbon dioxide, 1 molecule water Produced: 1 molecule water, urea
Used: 2 molecules of ammonia, 1 molecule water Produced: 1 molecule water, urea
Used: 1 molecule ammonia, 2 molecules carbon dioxide, 1 molecule water Produced: 2 molecules water, urea
Used: 2 molecules of ammonia, 1 molecule oxygen, 1 molecule water Produced: 2 molecules water, urea
What is the process of detoxification of alcohol?
Ethanol --> Ethanal --> Ethanoic Acid --> Acetyl Coenzyme A
Ethanol --> Ethanoic Acid --> Ethanal --> Acetyl Coenzyme A
Ethanol --> Ethanoic Acid --> Lactate --> Acetyl Coenzyme A
Ethanol --> Lactate --> Ethanoic Acid --> Acetyl Coenzyme A
Ethanol --> Ethanal --> Acetate --> Acetyl Coenzyme A
What is NAD used for in the liver?
Detoxification of alcohol and breakdown of fatty acids
Synthesis of bile and breakdown of fatty acids
Detoxification of alcohol and synthesis of bile
Detoxification of alcohol and control of amino acid levels
Control of amino acid levels and synthesis of bile
Which parts of the kidney are in the medulla?
Loop of Henle and collecting duct
Loop of Henle, collecting duct and DCT
Loop of Henle, collecting duct, DCT and PCT
Glomerulus, Bowman's capsule, PCT and DCT
Glomerulus, Bowman's capsule, PCT, DCT and collecting duct
Glomerulus, Bowman's capsule and PCT
What is filtered out of the blood during ultrafiltration? (Choose more than one answer)
water
plasma proteins
amino acids
glucose
urea
inorganic ions
red blood cells
white blood cells
platelets
plasma
Which of the following are adaptations that aid ultrafiltration?
pores in the endothelium of capillaries
pores in the membrane of the Bowman's capsule
a basement membrane made out of a matrix of collagen fibres to filter out large particles
podocytes in the Bowman's capsule being arranged in finger like projections to allow molecules to pass
the afferent arteriole narrowing into the glomerulus to increase hydrostatic pressure
the efferent arteriole wraps around the PCT so any products left in the blood can diffuse into the PCT
How is the PCT specialised to be adapted to selective readsorption? (Choose more than one answer)
the cell surface membrane is folded into microvilli to increase the surface area available for reabsorption
the cell surface membrane contains co-transporter proteins for facilitated diffusion
the cell surface membrane contains sodium-potassium ion pumps
the cell cytoplasm has many mitochondria to provide ATP for facilitated diffusion
What is the arrangement for water reabsorption in the Loop of Henle called?
a hairpin countercurrent multiplier
a paperclip countercurrent system
a hairpin opposing current
a countercurrent osmotic flow
a transmuting permeability countercurrent flow
Where are osmoreceptor cells found?
the hypothalamus
the posterior pituitary gland
the anterior pituitary gland
the medulla oblongata
the amygdala
Where is ADH secreted from?
the adrenal gland
What is haemodialysis?
The peritoneum (abdominal membrane) acts as a filter. The dialysate is poured into the body through a tube, and needs to be changed every few hours.
Blood is taken from a vein and passed through a dialysis machine so that exchange of substances can occur across a partially permeable membrane.
Blood is removed from the body and replaced with blood from healthy donors.
A new kidney is implanted into the lower abdomen and attached to the blood supply and bladder.
What is the name of the hormone secreted by the placenta that is used in pregnancy testing?
Human chorionic gonadotrophin (hCG)
Foetal cholinergic gonadotrophin (fCG)
Human cholinergic gonadotrophin (hCG)
Haemo chorionic gonatroponin (hCG)
Foetal chorionic gonatroponin (fCG)
What are the pores in the wall of the DCT and collecting duct called?
Aquaporins
Osmotic pores
Luminal pores
Podocytes
Osmoporins
