Excretion

Question 1

What is an endotherm?

Answer 1

Organism generatiing it’s own heat

Question 2

What term is used to describe animals which are not endotherms?

Answer 2

Ectotherms

Question 3

Suggest advantage of being an endotherm.

Answer 3

Can adapt to different environments rather than depending on external environment for heat

Question 4

What is meant by the term excretion?

Answer 4

Removal of metabolic wastes in the body.

Question 5

Mention one method of excretion in flowering plants.

Answer 5

Plants get rid of oxygen trough stomata on underside of leaves

Question 6

Name blood vessel that supplies blood to kidney.

Answer 6

Aorta

Question 7

Name one substance, other than water, excreted in the urine.

Answer 7

Salt

Question 8

Give a feature of kidney which indicates that it’s an exocrine gland.

Answer 8

Exocrine glands release their product into ducts. Kidney releases urine into ureter, therefore it’s exocrine

Question 9

A sample of urine was found to contain protein. Is that normal? Explain

Answer 9

No. Proteins are required by body and should be reabsorbed into nephron

Question 10

A sample of urine was found to contain glucose. Is that normal? Explain

Answer 10

No, glucose is useful for body.

Should be reabsorbed in proximal convoluted tubule.

Question 11

Urea is a excretory product. Name a substance from which it’s derived from.

Answer 11

Protein decontamination

Question 12

Carbon dioxide is a excretory product. Name a substance from which it’s derived from.

Answer 12

Lipids or carbohydrates

Question 13

Give a part of nephron in which REABSORPTION of amino acids takes place.

Answer 13

Proximal convoluted tubule.

Question 14

Give features of nephron that aid FILTRATION.

Answer 14

Thin walled, only one cell thick, high concentration of mitochondria to provide energy for active transport.

Question 15

Suggest 2 situations which may result in a drop in the water content of blood.

Answer 15

Exercise and salty diet.

Question 16

When water content of bloos drops a hormone is released. Name it and the endocrine gland from which it’s secreted.

Answer 16

Anti - diuretic hormone

Piturity gland

Question 17

Give a precise target area of the anti- diurectic hormone.

Answer 17

Distal convoluted tubule and collecting ducts are reached through the bloodstream.

Question 18

Explain the role of the anti- diurectic hormone at it’s target area, when the water content of the blood is low.

Answer 18

Causes the walls of the distal convoluted tubule to become more permeable with water, thus more waste is reabsorbed into nephron.

Question 19

Explain the term plasma filtrate:

Answer 19

Plasma is a liquid part of blood.

Question 20

Explain the term glomerular filtrate.

Answer 20

Plasm that has entered the Bowmans capsule.

Question 21

Why are red blood cells normally absent from glomerular filtrate.

Answer 21

Red blood cells are typically too big to pass into Bowmans capsule.

Question 22

Concentration of glucose is the same in plasma and filtrate. Why?

Answer 22

Glucose is small enough to pass through and is reabsorbed back into glomerular.

Question 23

State the precise location in the body where urea is made.

Answer 23

In the liver

Question 24

Where does urea enter the blood?

Answer 24

The hepatic artery

Question 25

Name a food source from which urea is derived.

Answer 25

Protein

Question 26

State precise location where in the nephron Filtration occurs.

Answer 26

bowmans capsule / glomerulus

Question 27

State a precise location where REABSORPTION of valuble nutrients occurs in kidney.

Answer 27

Loop of henle

Proximal convoluted tubule

Question 28

List two differences between blood and glomerular filtrate.

Answer 28

No protein in glomerular filtrate

No blood cells in glomerular filtrate

Question 29

Describe the role of the skin in controlling body temperature.

Answer 29

Cold: maintains body temperature in cold conditions
-> erector muscles in skin causes hairs to stand on end- traps layer of air/ blood vessels in skin also contract and move away from surface to prevent any heat loss
Warm: blood vessels dilate and move to surface- heat loss
-sweat is produced and released on skin and when evaporates it lowers body temperature.