Topic 7 - Animal Coordination, Control And Homeostasis

Question 1

Hormone

Answer 1

Chemical messengers sent in the blood to a target organ

Question 2

What produces hormones

Answer 2

Endocrine Glands

Question 3

Pituitary Gland

Answer 3

Release hormones that act on other glands, referred to as the ‘master gland’

Question 4

Thyroid Gland

Answer 4

Thyroxine produced which regulates: Metabolism, heart rate and temperature

Question 5

Ovaries

Answer 5

Oestrogen

Question 6

Testes

Answer 6

Produce Testosterone controlling puberty and sperm production

Question 7

Adrenal Gland

Answer 7

Adrenaline

Creates a ‘fight or flight response’

Question 8

Pancreas

Answer 8

Produce insulin and glucagon regulating glucose

Question 9

Hormones and Neurones

Answer 9

Neurones:
Fast action
Short duration
Precise areas

Hormones:
Slow Action
Long duration
General areas

Question 10

Adrenaline

Answer 10

From Adrenal Gland (above kidney)after brain spots a hazard.

1. Binds to heart receptors increasing heart rate, increasing blood flow so it receives more glucose and oxygen for respiration.
2. Binds to liver receptors breaking down glycogen to glucose,

Question 11

Negative feedback

Answer 11

Hormones are regulated, if it exceeds its specified amount a response will occur to bring it back to normal.

Question 12

Metabolism

Answer 12

The rate chemical reactions occur

Question 13

Thyroxine homeostasis

Answer 13

TOO LOW:
Hypothalamus releases TRH.
TRH stimulates Pituitary to release TSH
TSH stimulates Thyroid to release Thyroxine (and rises)
TOO HIGH:
TRH Inhibited (therefore TSH) reducing production of Thyroxine

Question 14

TRH

Answer 14

Thyrotropin Releasing Hormone

Question 15

TSH

Answer 15

Thyroxine Releasing Hormone

Question 16

Menstruation Cycle 4 stages

Answer 16

Stage 1: Day 1:
Lining on Uterus breaks down and released.
Stage 2: Day 4 - 14:
Uterus lining builds up. For the arrival of the egg.
Stage 3:
Egg develops and released. (OVULATION day 14)
Stage 4: Day 14-28
Lining is maintained until no fertilised egg lands by Day 28.

Question 17

Treat infertility

Answer 17

Clomifene Therapy, IVF

Question 18

Clomifene Therapy

Answer 18

If failure to ovulate is the cause.

Clomifene can be used as it contains FSH and LH. This stimulates ovulation and maturation.

Question 19

IVF (“In Vitro Fertilisation”) example of ART: Assisted Reproductive technology

Answer 19

Eggs are collected from ovaries and fertilised using sperm in a lab. Once an embryo. FSH and LH given.

Question 20

Hormones and contraceptives

Answer 20

Taking Oestrogen daily can inhibit release of egg due to inhibit of FSH.
Progesterone can be used as it stimulates cervical mucus production which blocks sperm in the cervix.
Eg. ‘Mini pill’, contraceptive injection,

Question 21

Barriers and contraception

Answer 21

Condoms, diaphragm

Question 22

Hormone vs barrier

Answer 22

Hormonal more effective.
But may have side-effects.
Don’t prevent STIs

Question 23

Homeostasis

Answer 23

Maintaining internal environment.

Question 24

Examples of homeostasis

Answer 24

Osmoregulation, Thermoregulation, Blood Glucose

Question 25

Negative feedback systems

Answer 25

A response is triggered to counteract the change

Question 26

Lipids forming

Answer 26

When there is excess glucose for metabolism. It can be stored as glycogen in the liver and muscles. When full lipids form in the tissue.

Question 27

Glucose levels too high

Answer 27

Insulin released by pancreas. It reaches the liver and causes glucose to be stored as glycogen.

Question 28

Blood glucose levels too low.

Answer 28

Glucagon released by pancreas. Glucagon causes liver to turn glycogen to glucose.

Question 29

Type 1 diabetes

Answer 29

Pancreas produces insufficient amounts of insulin. Meaning the homeostasis is uncontrolled, could cause death. Treated using Insulin Therapy, once food has been digested an injection into subcutaneous tissue to reduce the rise in sugars. Also may limit intake of simple carbohydrates and increase exercise to use up glucose.

Question 30

Type 2 diabetes

Answer 30

Where pancreas produces insufficient or a resistance (doesn’t respond) so sugar levels rise. Correlated with obesity (BMI 30+ / Waist-to-Hip >1 meaning around abdomen) Controlled through healthy diet, exercise and weight loss. Some have medication or Insulin therapy.

Question 31

Theroregulation

Answer 31

Hypothalamus measures the internal temperature (37C) and communicate with epidermis and derma for external temperatures and trigger a response to counteract.

Question 32

Thermoregulation, TOO HOT

Answer 32

Erector muscles relax, lie flat. Sweat secreted from sweat glands through pores. When it evaporates it transfers energy away. Blood vessels close to skin dilate (vasodilation) allowing blood flow near surface to transfer energy to surroundings.

Question 33

Thermoregulation, TOO COLD

Answer 33

Erector muscles contract. Hair stand on end to trap a layer of air near the surface. Little sweat. Blood vessels constrict (vasoconstriction) Less blood flow near surface to minimise energy loss. Shivering (muscles contract) increasing rate of respiration to transfer more energy.

Question 34

Osmoregulation

Answer 34

Keep cells functioning properly. If too high water will osmose into surrounding cells. If too much the cells will burst. If Too Low water will osmose out of cells into the blood. Kidneys control how much water is reabsorbed.

Question 35

Kidneys

Answer 35

1.Removal of urea (excess amino acids from liver) 2.Adjust ion level in blood 3.Adjust water content in blood. (All done by filtering under pressure.

Question 36

Kidney process

Answer 36

In Nephrons: 1. Liquid part of blood (water, urea etc) forced out of glomerulus into Bowman capsule at high pressure. Larger molecules can’t pass through so aren’t forced out. 2.All of liquid components flow along the nephron and reabsorbed. -all glucose selectively absorbed -ions -water All which isn’t absorbed passes through the ureter and out the urethra.

Question 37

Water content

Answer 37

Controlled by anti-diuretic hormone (ADH) Brain monitors content and instructs pituitary gland to release ADH. ADH makes collecting ducts in nephrons to be more permeable. (To reabsorbed)

Question 38

ADH Water loss

Answer 38

Brain detects Pituitary gland release ADH. ADH makes kidney reabsorb.

Question 39

ADH WATER GAIN

Answer 39

Brain detects. Pituitary gland produces less ADH. Kidney reabsorbs Less.

Question 40

Blood dialysis machine.

Answer 40

Filter for the patient. Removes waste and keeps substances at correct concentrations. Dialysis Fluid has the same concentration of salts and glucose so none is removed. Barriers are permeable to ions and waste but not larger.

Question 41

Kidney Transplant

Answer 41

Taken from donor. Voluntary or after sudden death. | Must be closely matched and anti-rejection drugs taken to prevent an immune response.