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Flashcards in Coordination in humans Deck (30)
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1
Q

Give two examples of homeostasis

A

Osmoregulation (body water content)

Thermoregulation (body temperature)

2
Q

What is thermoregulation

A

Temperature regulation

3
Q

Why is thermoregulation important?

A

Enzymes denature if temp too high
Cell membranes become fragile as temp rises
Diffusion rates rise with night temps and fall with lower temps
Liquids such as blood become more viscous (thicker) as temp falls

4
Q

What controls thermoregulation

A

The hypothalamus

5
Q

Protective functions of the skin

A

Tough water proof barriers between body and external environment
Regulates body temp
Contains sensory receptors to detect external environment changes
Protection from infection

6
Q

What are the two main layers in the skin

A

The upper epidermis and lower dermis

7
Q

What is the function of melanin

A

Absorbs ultraviolet light and protects the cells DNA from damage

8
Q

Mammals and birds are what?

A

Endotherms

9
Q

What can endotherms do

A

Maintain an internal environment that doesn’t change when external environmental temperatures change

10
Q

Amphibians reptiles insects and fish are what

A

Ectotherms

11
Q

Why can endotherms survive extreme temperatures better?

A

Temperature affects Ectotherms a lot more

12
Q

Which animal will lose heat more quickly. A mouse or an elephant?

A

A mouse because it has a big surface area to volume ratio

13
Q

What happens to sweat glands in the cold?

A

Sweat is not produced so sweat doesn’t move onto skin surface

14
Q

What happens to sweat glands in hot temps

A

Sweat produced, water in sweat evaporates from the skin. This uses heat energy from the blood which will reduce heat energy and so cool you down

15
Q

Why is it important for organism to control their internal environment?

A

So enzymes can control cell function and enzymes need specific conditions to work efficiently

16
Q

Name two ways in which organisms achieve this coordination

A

Through hormonal control (endocrine control)

Through nervous control (nervous system)

17
Q

What is the stimulus

A

Change in environment that triggers a reaction (eg a stimulus effects an endocrine gland to release a hormone)

18
Q

What is the receptor

A

This receives the stimulus (e.g a receptor molecule on a cell membrane for a hormone)

19
Q

What is the effector

A

The part of the organism that carries out the reaction to the stimulus (e.g a muscle or a gland)

20
Q

What are glands?

A

Small structures responsible for making and secreting specific chemicals

21
Q

What hormone is secreted by the pituitary gland in the brain?

A

A.D.H anti-diuretic hormone

Hormone for water regulation

22
Q

What do the adrenal glands produce?

A

Adrenaline

23
Q

Where are the adrenal glands?

A

Above the pancreas

24
Q

What does pancreas secrete

A

Insulin

Controls blood sugar levels

25
Q

What do the ovaries produce

A

Oestrogen and progesterone

26
Q

What do the testis (singular) testes(plural) produce

A

Testosterone

27
Q

How can you tell endocrine glands and exocrine glands apart?

A

Exocrine glands have tubes which secretes the hormones where as endocrine glands are just there.
ONE HAS A TUBE OR DUCT THAT LEADS/CONNECTS IT TO ANOTHER PART OF THE BODY

28
Q

How do hormones work when they reach their target organs?

A

They lock onto receptor on their target cells. This triggers a reaction. Afterwards the hormones travel to the liver and are broken down

29
Q

Explain how the adrenal gland can help an athlete running (e.g Ella because she’s a bloody pro)

A

Adrenaline is produced and passed into the blood, the breathing rate becomes quicker causing more oxygen to be taken in and more carbon dioxide removed. The heart beats faster so more oxygen is passed into the blood. This means that more respiration occurs and more energy ATP and glucose is released which increases blood sugar levels. This gives the athlete more energy and they can run faster and for longer.

30
Q

What is homeostasis

A

Maintaining a constant internal environment