Lesson 2: Human excretory systems

Question 1

Heat stress response and cold stress resonse

Answer 1

look at unit 4 lesson 1

Question 2

How does the excretory system help maintain homeostasis?

Answer 2

The excretory system helps maintain homeostasis by filtering out metabolic waste, balancing pH, and monitoring pressure.

Question 3

Nitrogenous Waste

Answer 3

3 main types are:

• ammonia
• urea
• uric acid
• this type of waste is a by-product of protein digestion. The amino group is removed through a process called deamination which occurs in the liver. The product of deamination is ammonia.

Question 4

know how to label a nephron and kidney

Answer 4

ok

Question 5

Hoe does ADH work to control water balance?1

Answer 5

The release of ADH by the piturity gland helps the kidneys to regulate the osmotic concentration of body fluids. ADH does this by making the upper part of the distal tubule and collecting duct permeable to water.The water leaves the upper part of the distal tubule and enters the blood, making the urine more concentrated.

Question 6

How does the bicarbonate buffer help the kidneys to regulate blood pH through negative feedback.

Answer 6

• if the blood pH is too high the carbonate ion bonds to any excess H+ ions to form carbonic acid and so lower blood pH.
• if the blood pH is too low the carbonic acid breaks down into H+ ions and water, in order to raise the blood pH.

Question 7

If an individual has a disease that hinder the functioning of the loop of Henle, what effects might this have?

Answer 7

Water will be lpst from the body and excreted in the urine, and blood volume and blood pressure may decrease.

Question 8

What are some benefits of taking vitamin supplements?

Answer 8

• folic acid is benefical to preganant women as it may reduce fetal neuraltube defcets. It is also beneficial to middle-aged individuals as it may reduce their risk of cardiovascular disease.
• Vitamin D supplements may reduce the risks of some cancers, particularly in individuals who get little exposure to sunlight, like the majority of Canadians during winter.

Question 9

What are some of the dangers of consuming excessive amounts of vitamins and supplements?

Answer 9

An excess of fat-soluble vitamins cannot be excreted. This causes calcium to build up in soft tissue, resulting in heart and kidney damage.

Question 10

How does a diet that is well balanced in vitamins help to maintain good health?

Answer 10

A balance diet will prevent nutritional deficiencies and replace the need for excessive amount of vitamins, and is the safest way to ensure good health.