homeostasis and response (p2)

Question 1

What is homeostasis?

Answer 1

regulation of the internal conditions of a cell or organism to maintain optimum conditions

Question 2

What conditions are controlled in the human body?

Answer 2

• blood glucose concentration * body temperature * water levels

Question 3

What two types of responses happen in the body to control conditions?

Answer 3

nervous responses or chemical responses

Question 4

What three parts are present in all control systems?

Answer 4

1. receptors
2. coordination centres
3. effectors

Question 5

In the body control system: what do cells called receptors do?

Answer 5

detect stimuli (changes in the environment)

Question 6

In the body control system: what do coordination centres do?

Answer 6

receive and process information from receptors

Question 7

Give examples of coordination centres in the human body

Answer 7

the brain, spinal cord and pancreas

Question 8

In the body control system: what do effectors do?

Answer 8

bring about responses which restore optimum levels (of things like glucose and water)

Question 9

Give examples of effectors in the human body

Answer 9

muscles and glands

Question 10

What is the nervous system?

Answer 10

the body system that includes all of the nerve cells, the brain and the spinal cord

Question 11

What does the nervous system do?

Answer 11

allows humans to react to their surroundings and to coordinate their behaviour

Question 12

What is the central nervous system?

Answer 12

the brain and spinal cord

Question 13

What does the central nervous system do?

Answer 13

it coordinates the response of effectors (which may be muscles contracting or glands secreting hormones)

Question 14

What is the name given to the part of the nervous system which contains only nerves?

Answer 14

The peripheral nervous system.

Question 15

What happens in the body between a stimulus and a response?

Answer 15

stimulus → receptor → coordinator → effector → response

Question 16

What is a stimulus?

Answer 16

A change in external environment

Question 17

What is a reflex action?

Answer 17

An automatic and rapid nervous response which does not require the conscious part of the brain

Question 18

What does a sensory neurone do?

Answer 18

it transmits electrical impulses from receptors in the sense organs to the CNS

Question 19

What does a motor neurone do?

Answer 19

it carries electrical impulses from the CNS to effectors such as muscles or glands

Question 19

What does a synapse relay neurone do?

Answer 19

it transmits electrical impulses from sensory neurones to motor neurones

Question 19

What is the endocrine system?

Answer 19

the body system that includes hormones and glands

Question 20

What does the endocrine system do?

Answer 20

sends hormones around the body through the blood

Question 21

What are hormones produced by?

Answer 21

glands

Question 22

Which is faster: the nervous system or the hormonal (endocrine) system?

Answer 22

the nervous system

Question 22

What are hormones?

Answer 22

chemicals which are carried in the bloodstream. They cause effects to happen in organs.

Question 23

Which effects last longer: the nervous system or the hormonal (endocrine) system?

Answer 23

the hormonal (endocrine) system

Question 24

What does the pituitary gland do?

Answer 24

Produces many hormones which regulate body conditions. Some of these hormones act on other glands, which produce other hormones.

Question 25

Where is the pancreas?

Answer 25

Behind the stomach.

Question 25

Where is the pituitary gland?

Answer 25

At the base of the brain

Question 26

Where is the thyroid?

Answer 26

Along the front of the windpipe.

Question 27

Where are the adrenal glands?

Answer 27

One above each kidney.

Question 28

Where are the ovaries?

Answer 28

In the lower abdomen.

Question 28

Where are the testes?

Answer 28

In the scrotum.

Question 29

Where is blood glucose concentration monitored?

Answer 29

In the pancreas

Question 30

What is carbohydrate broken down into?

Answer 30

Glucose

Question 31

What happens when blood glucose levels are too high?

Answer 31

the pancreas produces the hormone insulin that causes glucose to move from the blood into the cells. In liver and muscle cells excess glucose is converted to glycogen for storage.

Question 32

What is type 1 diabetes?

Answer 32

the pancreas fails to produce sufficient insulin, so blood glucose can reach dangerously high levels

Question 33

How is type 1 diabetes controlled and treated?

Answer 33

with insulin injections

Question 34

What is type 2 diabetes?

Answer 34

the body cells no longer respond to insulin produced by the pancreas

Question 35

How can type 2 diabetes be controlled?

Answer 35

A carbohydrate controlled diet and an exercise regime

Question 36

Which type of diabetes is obesity a risk factor for?

Answer 36

Type 2 diabetes

Question 37

[𝐇𝐢𝐠𝐡𝐞𝐫] What happens when blood glucose levels are too low?

Answer 37

the pancreas produces the hormone glucagon that causes glycogen to be converted into glucose and released into the blood.

Question 38

[𝐇𝐢𝐠𝐡𝐞𝐫] What is negative feedback?

Answer 38

Receptors detect stimuli, like levels of a hormone being to high. The coordination centre organises a response and the effector produces a response which counteracts the change. The optimum level is restored.

Question 39

What happens at puberty?

Answer 39

reproductive hormones cause secondary sex characteristics to develop

Question 40

What are the main male and female reproductive hormones?

Answer 40

Male: testosterone Female: oestrogen (Oestrogen and testosterone are produced by both sexes).

Question 41

What is the main role of testosterone?

Answer 41

it stimulates sperm production

Question 42

Where is oestrogen produced?

Answer 42

In the ovaries

Question 43

Where is testosterone produced?

Answer 43

In the testes

Question 44

What four hormones control the menstrual cycle?

Answer 44

FSH, LH, oestrogen and progesterone.

Question 45

What do FSH and LH stand for?

Answer 45

Follicle-stimulating hormone. Luteinising hormone.

Question 46

How many days long is the menstrual cycle (usually)?

Answer 46

28

Question 47

What is the function of FSH?

Answer 47

causes maturation of an egg in the ovary

Question 48

What is the function of LH?

Answer 48

stimulates the release of an egg

Question 49

Which hormones are involved in maintaining the uterus lining?

Answer 49

Oestrogen and progesterone

Question 50

[𝐇𝐢𝐠𝐡𝐞𝐫] How does oestrogen interact with FSH and LH in the menstrual cycle?

Answer 50

Stimulates release of LH. Inhibits release of FSH.

Question 51

[𝐇𝐢𝐠𝐡𝐞𝐫] How does progesterone interact with FSH and LH in the menstrual cycle?

Answer 51

Inhibits release of both LH and FSH.

Question 52

What is contraception?

Answer 52

hormonal and non-hormonal methods of controlling fertility

Question 53

List hormonal methods of contraception

Answer 53

Oral contraceptive pills Patch Implant Injection The IUD (intrauterine device, or the coil)

Question 54

List barrier methods of contraception.

Answer 54

Condoms Diaphragms

Question 55

How do oral contraceptives control fertility?

Answer 55

they contain hormones to inhibit FSH production so that no eggs mature

Question 56

How do injections, implants or skin patches control fertility?

Answer 56

they slowly release progesterone to inhibit the maturation and release of eggs for a number of months or years

Question 57

How do barrier methods control fertility?

Answer 57

they prevent the sperm reaching an egg

Question 57

How do intrauterine devices control fertility?

Answer 57

they prevent the implantation of an embryo or release a hormone

Question 58

How do spermicidal agents control fertility?

Answer 58

they kill or disable sperm

Question 59

How does abstaining from intercourse control fertility?

Answer 59

this tries to make sure there are no sperm in the female reproductive system when an egg may be in the oviduct

Question 59

How do surgical methods control fertility?

Answer 59

they prevent the sperm reaching an egg by removing tubes in the reproductive systems

Question 60

What does sterilisation involve?

Answer 60

The falllopian tubes (which connect the ovaries to the uterus) or the sperm duct (the tube between the testes and penis) are cut or tied

Question 61

[𝐇𝐢𝐠𝐡𝐞𝐫] Give two ways that hormones are used to treat infertility

Answer 61

Fertility drugs, and IVF

Question 62

[𝐇𝐢𝐠𝐡𝐞𝐫] What are some disadvantages of hormonal fertility treatments?

Answer 62

* it is very emotionally and physically stressful * the success rates are not high * it can lead to multiple births which are a risk to both the babies and the mother.

Question 63

[𝐇𝐢𝐠𝐡𝐞𝐫] Describe the steps in In Vitro Fertilisation (IVF) treatment.

Answer 63

* IVF involves giving a mother FSH and LH to stimulate the maturation of several eggs. * The eggs are collected from the mother and fertilised by sperm from the father in the laboratory. * The fertilised eggs develop into embryos. * At the stage when they are tiny balls of cells, one or two embryos are inserted into the mother's uterus (womb).

Question 64

[𝐇𝐢𝐠𝐡𝐞𝐫] What is the role of thyroxine?

Answer 64

It stimulates the basal metabolic rate. It plays an important role in growth and development.

Question 65

[𝐇𝐢𝐠𝐡𝐞𝐫] What is the role of adrenaline?

Answer 65

It increases the heart rate and boosts the delivery of oxygen and glucose to the brain and muscles, preparing the body for 'flight or fight'.