Topic 5 - homeostasis and response

Question 1

Label the body

Answer 1

A= pituitary gland B=Thyroid C=Adrenal gland D=Pancreas E=Ovaries

Question 2

What is homeostasis

Answer 2

The regulation of internal environment to maintain the optimum conditions for cell and enzyme function

Question 3

What is the importance of homeostasis

Answer 3

To provide the optimum conditions to function properly, including enzymes

Question 4

2 ways of responding to internal change

Answer 4

Nervous system and endocrine system

Question 5

What is negative feedback

Answer 5

Automatic control systems that keep internal environment stable

Question 6

3 conditions that are regulated

Answer 6

Blood glucose levels, body temperature, water levels

Question 7

Nervous system sequence

Answer 7

Stimulus, receptors, coordiator, effector, response

Question 8

What controls temperature and where is it

Answer 8

Thermoregulatory centre in the hypothalamus

Question 9

How is temperature monitored by the body (2 ways)

Answer 9

Thermoregulatory centor has receptors sensetive to blood temperture skin has receptors sensitive to skin temp and sends ipulses to thermoregulatory system

Question 10

Changes when body temp is too high

Answer 10

vascodilation: blood vessels near surface of skin dilate so more heat is lost to environment sweat: evaporation of water takes away heat energy from skin surface

Question 11

Changes when body temp is too low

Answer 11

Vascoconstriction: blood vessels near surface of skin constrict so less heat lost to environment shivering : respirtion allows mucles to contract, and is exothermic so heat is released hairs sstand up: create insulating layer so less heat released

Question 12

What is the endocrine system

Answer 12

Coordination system that uses hormones to provide a long lasting response

Question 13

What is a hormone

Answer 13

Chemical messenger secreted by glnds

Question 14

Job of hormones

Answer 14

Travel in blood to target organ, to cause a response

Question 15

What secretes hormones

Answer 15

glands

Question 16

Pituitary gland job

Answer 16

control other glands

Question 17

Why is pituitary gland the maset gland

Answer 17

It secretes a range of hormones, some of which stimulate other glands to secrete hormones

Question 18

Role of pituitary gland in endocrine system

Answer 18

Secrete growth hormone, stimulate thyroid, ovulation, oestrogen production, sperm and testostirone production

Question 19

Effector function and what

Answer 19

Respond to stimuli, muscles/glands

Question 20

Thyroxine, where and what

Answer 20

Thyroid gland, metabolism, heart rate and body temperature

Question 21

Insulin where and what

Answer 21

pancreas, controls bood glucose levels

Question 22

Adrenline where and what

Answer 22

Adrenal gland, controls ‘fight or flight’ response

Question 23

Oestrogen where and what

Answer 23

Ovaries, coordinates menstral cycle and development of female secondary sexual development

Question 24

Testosterone where and what

Answer 24

Testes, coordinates production of sperm and development of male secondary sexual response

Question 25

Pancreas job

Answer 25

monitor and control blood glucose concentration

Question 26

Pancreas when blood glucose is too high

Answer 26

secretes insulin, which binds receptors on liver and muscles, causing excess glucose to be converted to glucogen and stored

Question 27

Pancreas when blood glucose is too low

Answer 27

Secretes glucagon, which binds to liver cells, causing glycogen to be converted to glucose to be released into blood

Question 28

How blood- glucose levels regulated by negative feedback loop

Answer 28

When levels are too igh ot low, hormone secreted by pancreas

Question 29

What is type 1 diabetes

Answer 29

autoimune disease where pancreas doesn?t produce sufficient enough insulin so blood-sugar levels often high

Question 30

3 symptoms of type 1 diabetes

Answer 30

Excessive urination, tiredness, weight gain

Question 31

How can type 1 diabetes be treated

Answer 31

Insulin injections, limiting carbohydrate intake, attempts using pancreas and pancreatic cell transpant

Question 32

What is typpe 2 diabetes

Answer 32

Disorder where body cels stop responding to insulin, leading to uncontrolled blood-glucose concentration

Question 33

3 risk factors of type 2 diabetes

Answer 33

obesity, age , being of south asian decent

Question 34

How can type 2 diabetes be treated

Answer 34

Balanced diet, exercise, drugs that increase insulin production and effectiveness

Question 35

What is the function of reproductive hormones during puperty

Answer 35

males: cause seconday sexual characteristic development females: cause development of secondary sexual characteristics and maturation of eggs

Question 36

What is tropism

Answer 36

The response of a plant to a specific stimulus

Question 37

What is phototropism

Answer 37

Response of pants shoot or root to light

Question 38

What is gravitropism

Answer 38

response of plants shoot or root to gravity

Question 39

what is auxin

Answer 39

The hormone that controls the groeth of a plant's shoots and roots.

Question 40

What does uneven distribution of auxine cause

Answer 40

the rate of grwoth will be unequal

Question 41

How do plants respond to phototropism

Answer 41

The sie of the plant in the shade recieves more auxin so grows faster and bends toward the light so photosynthesis can occur faster

Question 42

How plants negatively rspond to gravity

Answer 42

In horizontal shoots, auxin accumulates in lower side due to gravity, cells on lower side of shoot grow more, causing the shoot to bend away from the direction of gravity

Question 43

How do plants positively respond to gravity

Answer 43

In horizontal roots, auxin accumulates in lower side, cuasing cells to grow less, root bends in direction of gravity, so more nutrients are available

Question 44

What are gibberellins

Answer 44

Type of planty hormone involved in seed germination

Question 45

What is ethene

Answer 45

Type of plant hormne involved in cell division and ripening

Question 46

2 uses of auxins

Answer 46

Weedkillers as cells rapidly grow so kill the plants, rooting powder allowing new plants to grow at fast rate

Question 47

1 use of ethene

Answer 47

Controlng food ripening- allows fruit to be ripened just before they are sold

Question 48

3 uses of gibberellins

Answer 48

Termination of seed dormancy, promotion of flowering, increase fruit size

Question 49

what is seed dormacy

Answer 49

prevention of seeds germinating

Question 50

In what 3 ways is water lost from the body

Answer 50

During exhailation via the lungs, sweating, urine

Question 51

How are ions lost in the body

Answer 51

Sweating, urine

Question 52

How are excess amino acids extracted from the body

Answer 52

Excess amino acids are deaminated in the liver to form amonia, amonia is toxic so converted into urea which is excreted via sweat and urine

Question 53

How do the kidneys mintain the balance of water and other substances in the body

Answer 53

Ultrafiltration: filter blood to remove wate products, selective reabsorbtion: useful molecules selected, like glucose, water and ions

Question 54

What does ADH do

Answer 54

When blood too concentrated, more ADH secreted, which travels in the blood to kidney and increases the permeability of kidney tubles to water , more water is reabsorbed in kidneys, so more concentrated urine

Question 55

Why kidney failure is dangeous

Answer 55

A build up of toxic materials in body and uncontrolled ion/water balance in cells reulting in cell damage

Question 56

2 treatments for kidney failure

Answer 56

Dialysis and transplant

Question 57

what is kidney dialysis

Answer 57

Use of machines to carry out functio of kidney, dialysis fluid contains same concentration of glucose and ions as healthy blood, only excess and waste molecules herefore lost from blood and glucose and ions remain