Topic 7 - Animal Coordination, Control & Homeostatsis

Question 1

Hormones

Answer 1

• Chemical Messenger
• Stimulates a process to occur
• Secreted by glands

Question 2

Endocrine Glands:

Answer 2

• Pituitary Gland (Brain)
• Thyroid Gland (Throat)
• Pancreas (Centre of Bod)
• Adrenal Gland (On top of Kidneys)
• Testes
• Ovaries

Question 3

How Hormones are Transported:

Answer 3

• Hormones travel through blood to target cell
• They bind to cell’s receptors

Question 4

How does adrenalin prepare the body for fight or flight

Answer 4

• increased heart rate
• increased blood pressure
• increased blood flow to the muscles
• raised blood sugar levels

Question 5

How does thyroxine controls metabolic rate as an example of negative feedback?

Answer 5

• Low levels of thyroxine stimulates production of TRH in hypothalamus
• This causes release of TSH from the pituitary gland
• TSH acts on the thyroid to produce thyroxine
• When thyroxine levels are normal thyroxine inhibits the release of TRH and the production of TSH

Question 6

Menstrual Cycle: Stage 1

Answer 6

• Day 1-7, Menstruation
  ↑FSH ↓Oestrogen

Question 7

Menstrual Cycle: Stage 2

Answer 7

• Day 7-14, Uterus Rebuilding
  ↑LH ↓Progesterone

Question 8

Menstrual Cycle: Stage 3

Answer 8

Day 14, Ovulation
↑Oestrogen ↓FSH ↓LH

Question 9

Menstrual Cycle: Stage 4

Answer 9

Day 14-28, Uterus Maintained
↑Progesterone ↓FSH ↓LH

Question 10

How does hormonal contraception influence the menstrual cycle and prevent pregnancy?

Answer 10

• Pill contained Progesterone
• Uterus is maintained, no ovulation, no egg is fertilised

Question 11

Factors of Barrier Contraception:

Answer 11

+ Prevents STIs
+ Immediate effectiveness
- Can break
- Can be hard to apply

Question 12

Factors of Hormonal Contraception:

Answer 12

+ Provide long-lasting protection
+ Very effective
- Doesn’t protect against STIs
- Has side effects like irregular vaginal bleeding

Question 13

Hormones in IVF:

Answer 13

• Ovarian stimulation
• Triggers ovulation

Question 14

Hormones in Clomifene therapy

Answer 14

• Ovulation stimulation
• Timing intercourse

Question 15

Why is homeostasis important?

Answer 15

• Ensures reactions in the body cells can function

Question 16

Why is homeostasis important specifically for thermoregulation?

Answer 16

• So enzymes can function in metabolism

Question 17

Why is homeostasis important specifically for osmoregulation?

Answer 17

• Uneven water:salt ratio can cause cells to burst or shrivel

Question 18

What is the role of the dermis?

Answer 18

• Allows for vasodilation and constriction

Question 19

What is the role of the epidermis?

Answer 19

• Acts as a protective barrier

Question 20

What is the role of the hypothalamus?

Answer 20

• Regulates temperature with negative feedback
• Acts as a thermostat

Question 21

Why is shivering a feature of thermoregulation?

Answer 21

• Muscles contract, so respiration (an exothermic reaction) takes place, which releases heat energy

Question 22

Why is vasoconstriction a feature of thermoregulation?

Answer 22

• When cold, vessels narrow to prevent heat energy emissions from blood to skin

Question 23

Why is vasodilation a feature of thermoregulation?

Answer 23

• When hot, blood vessels expand to allow blood to emit heat from the skin

Question 24

How does insulin control blood glucose level?

Answer 24

When BG is HIGH:
- Insulin binds to cells to cause blood to be absorbed
- The glucose in blood is converted to glycogen

Question 25

How does glucagon control blood glucose level?

Answer 25

When BG is LOW: - Stimulates cells to breakdown glycogen into glucose

Question 26

Type 1 Diabetes: - what is it - how its controlled

Answer 26

- Pancreas cannot produce insulin - Inject insulin, exercise and diet

Question 27

Type 2 Diabetes: - what is it - how its controlled

Answer 27

- Insulin cannot bind to cells - Low sugar diet and exercise

Question 28

Correlation between BMI and Type 2 Diabetes:

Answer 28

Higher BMI, higher Type 2 Diabetes chance

Question 29

Correlation between waist:hip ratio and Type 2 Diabetes:

Answer 29

The bigger the circumference of the waist relative to the hip, the higher chance of getting Type 2 Diabetes

Question 30

Ultrafilteration

Answer 30

- Occurs between Glomerulus and Bowman's Capsules Filters molecules like: - Urea - Glucose - Water - Salts And forms a filtrate

Question 31

Reabsorption - Water

Answer 31

- Collecting Duct reabsorbs water due to osmosis (water:salt concentration)

Question 32

Reabsorption - Glucose

Answer 32

- Proximal convoluted tubule causes reabsorption in order to regulate blood glucose levels

Question 33

Kidney Function:

Answer 33

- Filter blood to remove waste and excess substances

Question 34

Ureters Function:

Answer 34

- Transport urine from the kidneys to the bladder using muscle contractions.

Question 35

Bladder Function:

Answer 35

- Store urine until it's ready to be expelled from the body during urination.

Question 36

Urethra Function:

Answer 36

Carry urine from the bladder to outside the body during urination

Question 37

ADH

Answer 37

- Higher ADH causes higher permeability in collecting ducts for water. allowing for more reabsorption

Question 38

Kidney Dialysis

Answer 38

- Artificial method of filtering the blood with a machine out of the body - Machine contains glucose and salt concentration similar to that in the blood

Question 39

Organ Donation advantages:

Answer 39

- Freedom - Less restricted diet - Cheaper then kidney dialysis - Long term

Question 40

Organ Donation disadvantages:

Answer 40

- Immune response can occur - Immunosuppressant drugs may be used - Not enough donors

Question 41

What creates urea?

Answer 41

- Excess amino acids in the liver