Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Biology Paper 2 > Homeostasis And Response > Flashcards

Homeostasis And Response Flashcards

You may prefer our related Brainscape-certified flashcards:
AP® Biology flashcards Biology 101 flashcards
1
Q

What is homeostasis

A

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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What happens if conditions are not optimal

A

Enzymes start to denature. This reduces their ability to catalyse metabolic reactions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What does homeostasis regulate

A

Water levels
Blood glucose concentration
Body temperature

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What do control centres include

A

Receptors
Coordination centres
Effectors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are receptors

A

Detect changes in environment

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are co ordination centres

A

Receive and process information from receptors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are effectors

A

(Muscles or glands) the bring about a response which restores optimum levels

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What does the nervous system do

A

Protects organisms from harm by responding to changes in the environment

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the process for a response

A

1) receptor cells convert a stimulus into an electrical impulse
2)this electrical impulse travels along cells called sensory neurones to the CNS
3) Here, the information is processed and the appropriate response is co ordinated resulting in an electrical impulse being sent along motor neurones to effectors
4)the effectors carry out the response. This may be muscles contracting or glands secreting hormones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the central nervous system made up of

A

The brain
The spinal chord
Neurones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are synapses

A

Gaps between neurones. Nerve impulses must travel across the gaps

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Why are reflexes important

A

They prevent the individual from getting hurt. This is because the information travels down a pathway called a reflex arc

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is a sensory neurone

A

Carries signal in form of electrical impulse to the CNS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is a relay neurone

A

Relays the electrical impulse from the sensory neurone to the appropriated motor neurone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is the motor neurone

A

Another nerve cell that carries the electrical impulse from the CNS to the effector

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is the process of a reflex

A

1)stimulus is detected by a receptor
2)impulses are sent along a sensory neurone
3)in the CNS impulses passes to a relay neurone
4)impulse sent down a motor neurone
5)reacher an effector resulting in a response

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is the process of synapses

A

1)the electrical impulse reaches the end of the neurone before the synapse
2)this triggers the release of chemicals called neurotransmitters
3)the neurotransmitters diffuse across the synapse
4) the neurotransmitters bind to receptors on the next neurone
5) the presence of the neurotransmitters causes the production of an electrical impulse in the next neurone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are examples of voluntary actions

A

Drinking
Talking
Running

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What are examples of reflex actions

A

Blinking
Coughing
Yawning

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is the reaction time required practical

A

1) Sit down on the chair and place your forearm of the non dominant hand on the table with your hand hanging over the end of the table
2) have your partner hold a ruler with the bottom end in between your fingers so you can practice holding the ruler with 2 fingers
3)have your partner hold the ruler and remove your fingers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Reaction time (2)

A

4)have your partner hold the ruler in line so that 0 mark is level with the top of your thumb
5)your partner will drop the ruler without telling you beforehand and you’ll catch the ruler as quickly as you can
6) note and record the number level with the top of your thumb after you’ve caught the ruler in a table such as below

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Reaction time (3)

A

7) repeat the test at least 5 times
8) swap places with your partner and repeat steps 1-7
9) find reaction times by using a conversion table to convert the ruler measurements

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What are the sources of error

A

Participants may have different experiences in performing a similar task previously

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What are hormones

A

Chemicals made and released by glands. They travel around the body in the blood to their target organ

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What are the endocrine glands

A

Testes
Ovary
Pituitary gland
Adrenal glands
Pancreas
Thyroid glands

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What is the pituitary gland

A

The master gland
Secrètes hormones into the blood to either have an effect on the body or act on other glands to stimulate them to produce different hormones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What is the pancreas

A

Secretes insulin
Controls blood glucose levels

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What are the thyroid glands

A

Secretes thyroxine
Controls metabolic rate, heart rate and temperature

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What are adrenal glands

A

Secretes adrenaline
Involved in the “fight” or “flight” response

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What are the ovaries

A

Secretes oestrogen
Involved in the menstrual cycle and the development of female secondary sexual characteristics

31
Q

What are the testes

A

Secretes testosterone
Involved in the production of sperm and the development of male secondary sexual characteristics

32
Q

What are the differences between the central nervous system and the endocrine system

A

CNS-triggers rapid response
Endocrine-triggers slower response
CNS-uses electrical signals carried by neurones
Endocrine-uses chemical messagers carried by blood
CNS-response is very short
Endocrine-response can be long lasting
CNS-acts on a precise part of body
Endocrine-acts on large areas of the body

33
Q

Why is the pituitary gland the master gland?

A

It produces multiple hormones and tells other glands to release their hormones. It secretes several chemicals and hormones into the blood in response to the body conditions. These hormones in turn act on other glands to stimulate other hormones into the blood in response to body conditions

34
Q

What happens if there’s a high concentration of glucose in the blood

A

Water moves out of the cells by osmosis across a partially permeable membrane from an area of high water concentration so cells will shrink

35
Q

What if there’s a low concentration of glucose in the blood

A

Water moves into the cells by osmosis across a partially permeable membrane from an area of high water concentration do cells will grow

36
Q

What happens when there’s an increase in blood sugar

A

When there’s an increase in blood sugar for example eating, the pancreas detects a rise in blood sugar and releases insulin into the blood. All the cells take in glucose. Liver and muscles turn excess glucose into glycogen and blood sugar falls.

37
Q

What happens when there’s decrease in blood sugar

A

When there’s a decrease in blood sugar for example exercise, pancreas detects the drop in blood sugar and releases glucagon in the blood which increases the blood glucose concentration. Glycogen in liver is broken down and glucose is released in the blood

38
Q

What does blood glucose concentration work in

A

Negative feedback loop

39
Q

How does the negative feedback loop create an opposite effect

A

The action of this hormone cannot occur continually because when the blood arrived at a certain glucose concentration the other hormone is produced resulting in the opposite effect

40
Q

What is type 1 diabetes

A

A disorder in which the pancreas fails to produce sufficient insulin.

41
Q

What is type 2 diabetes

A

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

42
Q

What are the differences between type 1 and 2 diabetes

A

Type 1-can be managed but not cured
Type 2- may be cured
Type 1-appears in children/young adults
Type 2-affects older/overweight people
Type 1-caused by
Type 2-caused by

43
Q

What are the treatments of type 1 diabetes

A

Insulin injections
Pancreatic cell transplants
Manage diet, exercise regularly

44
Q

What are the treatments of type 2 diabetes

A

Injections don’t help-body doesn’t respond to insulin
Losing weight
Increasing exercise
Drugs to make insulin more effective on body cells

45
Q

Why are insulin injections better than pancreatic transplants

A

Pancreatic transplants are complex surgery, high risk and expensive
Injections are widely available, self administered and cheap

46
Q

What are the secondary sex characteristics in men during puberty

A

Testosterone rises
Underarm, facial and Pubic hair grows
Voice deepens

47
Q

What are the secondary sex characteristics in women during puberty

A

Oestrogen rises
Triggers menstrual cycle
Underarm and pubic hair grows
Breasts enlarge

48
Q

What is the menstrual cycle

A

A monthly cycle which involves the maturation and release of an egg. If sex has occurred this can result in pregnancy

49
Q

What are the 4 hormones involved in the menstrual cycle

A

FSH (follicle stimulating hormone)
LH (luteinising hormone)
Oestrogen
Progesterone

50
Q

What does FSH do

A

Released by the pituitary gland and causes egg in ovary to mature
Stimulates production of oestrogen

51
Q

What does oestrogen do in the menstrual cycle

A

Released in ovaries. Causes development of uterus lining. Stimulates production of LH and stops production of FSH

52
Q

What does LH do in the menstrual cycle

A

Produced by pituitary gland and stimulates release of mature egg on day 14 of cycle
This is called ovulation

53
Q

What does progesterone do in the menstrual cycle

A

Produced in ovaries after ovulation. Maintains lining of uterus during days 14-28. When progesterone levels drop, this triggers the breakdown of the lining
Stops release of FSH + LH

54
Q

What are the stages of the menstrual cycle

A

1) (day 1-4) Progesterone levels drop meaning uterus lining breaks down resulting in a period
2) (day 4-14) due to oestrogen the uterus lining starts to develop
3) (day 14)- ovulation occurs from LH. FSH causes ovary to mature and this releases a mature egg
4) (day 15-28) the rise in progesterone maintains the uterus lining meaning that it’s now ready for the arrival of a fertilised egg. If no fertilised egg is attached to the uterus lining, the lining breaks down and the cycle begins again. If there’s a fertilised egg attached then pregnancy occurs

55
Q

What is the difference between hormonal and non hormonal methods of contraception

A

Non hormonal- stop the sperm and egg meeting
Hormonal-use hormones to prevent the egg maturing or being released

56
Q

What are the features of a contraceptive pill

A

Mixed pill contains oestrogen and progesterone
TMT oestrogen levels are constantly high inhibiting FSH so no eggs mature
The lining also stops developing and the mucus in the cervix becomes thick so sperm can’t move through
Possible side effects include-mood swings, depression, breast pain, increased blood pressure
Progesterone only pill- has less side effects stimulates production of mucus which is difficult for sperm to penetrate

57
Q

What are the features of contraceptive patches

A

Contains oestrogen and progesterone
Small and stuck on the skin
Lasts for one week

58
Q

What are the features of contraceptive implants

A

Releases a continuous amount of progesterone
Prevents the ovaries from releasing the egg thickens the mucus in cervix do sperm cannot swim and stops fertilised eggs from embedding in the uterus
Lasts for three years

59
Q

What are the features of contraceptive injections

A

Made up of progesterone
Same effect as the implant
Last for 2-3 months

60
Q

What are the features of plastic IUD S

A

Releases progesterone
Same effect as implant
T shaped- inserted into uterus

61
Q

What are spermicide- non hormonal

A

A fluid used which kills or disables sperm but are only 70-80% effective

62
Q

What are features of condoms and diaphragms (non hormonal)

A

Condoms are either worn over the penis or inside the vagina. They also prevent the individual from contracting STDs. A problem however is it can tear and let sperm through
A diaphragm is a plastic cup which is positioned over the cervix. It’s used with speemicide

63
Q

How do copper IUDs work

A

Work by killing sperm in the uterus and stopping any fertilised embryos from implanting in the uterus lining

64
Q

How does sterilisation work

A

A permanent procedure. For a man it involves cutting the sperm duct so the sperm isn’t released in ejaculation
For women this involves cutting the oviduct so that an egg can’t reach he uterus

65
Q

What are the natural methods of contraception

A

Timing-some women avoid sex ok days when they know they are ovulating. However it’s not as effective as sperm can last up to 6 days inside the womens body
Abstinence-a couple chooses not to have sex unless ready for a baby

66
Q

What are fertility drugs used for

A

To increase chances in pregnancy
The main hormones used are FSH and LH because they stimulate the maturation and release of an egg. The woman can then become pregnant normally

67
Q

What happens in IVF treatment

A

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 a 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 mothers uterus

68
Q

What are the benefits of IVF

A

provides a way for an infertile couple to have a child

69
Q

What are the disadvantages of IVF

A

It’s physically stressful as women may have reactions to the hormones such as feeling sick
It’s emotionally stressful because it may not work. The success rate for IVF is 26%
It can lead to multiple births- unexpected and may be a risk to the babies and the mother
Can be expensive if the process needs to be repeated

70
Q

What does thyroxine do

A

Regulates metabolic rate. It’s also important in growth an development by stimulating protein synthesis
Released by the thyroid gland
Release is stimulated by the thyroid stimulating hormone

71
Q

What is thyroxine in negative feedback

A

When the levels increase it’s detected by the receptors in the brain
This inhibits the release of TSH
this inhibits the release of thuroxine so levels fall

72
Q

What does adrenaline do

A

Produced in times of stress and stimulates the “fight” or “flight” response
Released by the adrenal glands
Stimulated by fear or stress detected in the brain

73
Q

What organs does adrenaline carry around

A

Heart
Lungs
Liver
Eyes
Brain

74
Q

What are the effects of adrenaline

A

Increased heart rate and breathing rate to deliver more oxygen and glucose to the brain and muscles for resperation
Glycogen stored in liver is converted to glucose for resperation
Pupils dilate to let in more light
Blood flow to muscles is increased
Blood flow to digestive system increased

Biology Paper 2 (3 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions