Response and Regulation 2

Question 1

What is the endocrine system?

Answer 1

A system that sends messages around the body through hormones

Question 2

How does information travel in the endocrine system?

Answer 2

In form of hormones + In the blood + Slowly

Question 3

What is the difference between the effects brought along by the nervous system and endocrine system?

Answer 3

Electrical impulse effects end quickly while hormones have a lasting effect

Question 4

Where are hormones produced?

Answer 4

Organs called endocrine glands

Question 5

What are glands?

Answer 5

Specialised organs that release hormones. They have a dense network of blood capillaries to secrete hormones into.

Question 6

What are examples of endocrine glands?

Answer 6

Pituitary gland, thyroid, and adrenal gland

Question 7

Where is the pituitary gland located?

Answer 7

At the base of the brain

Question 8

Which hormone does the adrenal gland produce and what function does it serve?

Answer 8

Adrenaline

Prepares the body for activities that need energy and quick reflex actions (fight or flight)

Question 9

Which hormones does the pancreas produce and what function do they serve?

Answer 9

Insulin
Makes liver reduce blood glucose level

Glucagon
Makes liver increase blood glucose level

Question 10

Which hormone do the testis produce and what function does it serve?

Answer 10

Testosterone

Produces male secondary sexual characteristics

Question 11

Which hormones do the ovaries produce and what function do they serve?

Answer 11

Oestrogen
Produces female secondary sexual characteristics

Progesterone
Helps control menstrual cycle and maintain pregnancy

Question 12

What is homeostasis and why is it important?

Answer 12

The regulation of our body’s internal conditions in response to a change in environment to ensure our enzymes and cells function well. Otherwise, they could denature.

Question 13

Which conditions inside of our body need to be regulated?

Answer 13

Carbon dioxide levels
Blood sugar (glucose) levels
Urea concentration in urine
Internal body temperature
Water levels

Question 14

What is negative feedback?

Answer 14

When an internal condition changes to be no longer optimal and the body works to counteract (reverse) the change and return conditions to the optimum.

Question 15

What does the negative feedback loop involve?

Answer 15

1. Internal condition changes
2. Change detected
3. Corrective mechanisms activated
4. Conditions return to normal
5. Corrective mechanisms deactivated

Question 16

What are the side-effects of having too much glucose?

Answer 16

If blood glucose levels are too high, this can have a negative impact on osmosis (movement of water between cells) by affecting concentration gradients

Question 17

What are the side-effects of having not enough glucose?

Answer 17

Glucose is important for respiration.
Respiration releases the energy needed by every living cell.
If there is not enough glucose, an organism cannot produce enough energy.

Question 18

How will the body try to bring glucose levels back to normal (in general)?

Answer 18

The negative feedback loop

Question 19

What is glycogen?

Answer 19

An insoluble form of glucose that can be stored for later

Question 20

What is glucagon?

Answer 20

A hormone formed in the pancreas which promotes the breakdown of glycogen to glucose in the liver

Question 21

What happens when blood glucose is too low?

Answer 21

Glucagon is released from the pancreas which stimulates the liver to convert stored glycogen to glucose and release it into the blood

Question 22

What happens when blood glucose is too high?

Answer 22

Insulin is released from the pancreas which stimulates the liver to take in excess glucose which is stored as glycogen

Question 23

What vital life process is glucose required for?

Answer 23

Respiration

Question 24

When would someone’s blood glucose levels increase?

Answer 24

When a person eats food containing glucose

Question 25

When would someone's blood glucose levels decrease?

Answer 25

When glucose is used up in respiration e.g. exercise

Question 26

What is type 1 diabetes?

Answer 26

When the pancreas cells are unable to produce enough insulin, meaning glucose is not being reduced Blood sugar is TOO HIGH

Question 27

How can type 1 diabetes be treated?

Answer 27

Injecting insulin when blood glucose levels rise too high + managing diet and exercising properly

Question 28

What is type 2 diabetes?

Answer 28

When insulin is still produced, but the body no longer responds to it Blood sugar is TOO HIGH

Question 29

How can type 2 diabetes be treated?

Answer 29

Insulin injections do not help because the body no longer responds to it. Diet and exercise must be regulated

Question 30

What are the symptoms/side effects of diabetes?

Answer 30

``` Weight loss Urination Increased thirst Tiredness Blurry vision Wounds take longer to heal Thrush ```

Question 31

How would you test a urine sample for glucose?

Answer 31

Add equal volumes of Benedict’s reagent and the urine sample to a boiling tube and heat in a hot water bath. If a red precipitate is formed, glucose is present. OR using reagent test strips which are dipped into urine and change colour to indicate the concentration of glucose present

Question 32

What is the control of body temperature called?

Answer 32

Thermoregulation

Question 33

What could happen if our body temperature becomes too high?

Answer 33

The enzymes that control the chemical reactions in oour body that keep us alive could denature

Question 34

How does our body monitor temperature?

Answer 34

Receptors on the surface of the skin track our external body temperature Receptors in the hypothalamus in the brain monitor our internal body temperature as blood flows through the brain

Question 35

What are the three sections of the sweat producing body part called and what do they do?

Answer 35

Sweat gland - Produces sweat Sweat duct - Tube that sweat travels through Sweat pore - Where sweat leaves the skin

Question 36

How does our body respond to temperature being too low?

Answer 36

Blood vessels constrict (vasoconstriction) Hairs stand on end Shivering (muscle contractions)

Question 37

How does our body respond to temperature being too high?

Answer 37

Blood vessels get wider (vasodilation) Sweat produced Hairs remain close to skin

Question 38

What effect do blood vessels have on our body temperature?

Answer 38

When they are wider the blood flows nearer to the surface of the skin so heat can be lost by radiation. The opposite applies to when they constrict

Question 39

What effect do hairs standing on end have on our body temperature?

Answer 39

When they are raised they trap a layer of air close to the skin which insulates the skin. Even when they lie flat they still trap a layer of air, but it is thinner.

Question 40

What are the effectors involved in thermoregulation?

Answer 40

Muscles Sweat glands Hair erector muscles Blood capillaries

Question 41

How does shivering help us warm up?

Answer 41

The muscle movement requires energy generated through respiration. Respiration produces heat which warms us up

Question 42

How does sweating help us lose body heat?

Answer 42

Heat energy from the body is transferred to the layer of water which evaporates, taking the heat with it

Question 43

What are the types of phototropisms?

Answer 43

Positive phototropism: Growing towards a light source | Negative phototropism: Growing away from a light source

Question 44

What are the types of gravitropisms?

Answer 44

Positive gravitropism: Growth towards the direction of gravity Negative gravitropism: Growth away from the direction of gravity

Question 45

What is the purpose of the tropisms?

Answer 45

To ensure a plant will grow the right way up whatever direction their seed lies in the soil. They also ensure the shoots can grow towards the light for photosynthesis

Question 46

What are plant responses to stimuli brought about by?

Answer 46

Hormones called auxins. The concentration of the auxin on the side of the plant that is not receiving stimulus increases so growth occurs in the direction of the stimulus (cells elongate where auxins are present)

Question 47

Where in a plant are auxins produced?

Answer 47

The tip

Question 48

In what situations can a plant not produce auxins?

Answer 48

When the tip has been removed When the tip is obscured and so cannot receive light When the tip is separated from the rest of the plant by something auxins cannot diffuse across

Question 49

What are the functions of auxins in different locations in a plant?

Answer 49

In roots, auxins prevent elongation of cells. | In shoots, auxins promote elongation of cells.