B2: organisation Flashcards Preview

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Flashcards in B2: organisation Deck (122):
1

Salivary glands

Produces amylase enzyme in the saliva

2

Oesophagus/ gullet

Transports food from mouth to stomach

3

Stomach

Pummels food with its muscular walls

Produces protease enzymes (pepsin)

Produces hydrochloric acid for -killing bacteria
-to give the right PH for the protease enzyme to work

4

Liver

Bile is produced

5

Pancreas

•Produces protease, amylase, lipase enzymes

•Release the enzymes into the small intestine

6

Gall bladder

Bile is stored before being released in to the small intestine

7

Large intestine

Excess water is absorbed from food

8

Small intestine

•Produces protease , amylase and lipase enzymes to complete digestion
• where the digested food is absorbed out of the digestive system into the blood
• absorbs soluble food molecules

9

Rectum

Faeces are stored

10

Testing for sugar benedicts solution

BENEDICTS SOLUTION

1) 5cm3 Of food sample into a test tube
2) water bath set to 75 °c
3) add 10 drops of benedicts solution to the test tube using a pipette
4) place test tube in to the water bath and leave for 5 minuets
5) if the food sample contains sugar it will change from yellow to brick-red

11

Testing for starch- iodine solution

IODINE SOLUTION

1) 5cm3 Of food sample to test tube
2) add a few drops of iodine solution and gently shake the test tube

If it contains stretch it will change from a browny-orange to a black

12

Testing for proteins - using biuret solution

1) 2cm3 Of food into a test tube
2) add 2cm3 Of biuret solution to the sample and mix the contents
3) if contains proteins it should change from blue to pink/ purple

13

Testing for lipids - using ethanol

1) add ethanol to the solution
2) shake the test tube and leave for a minute
3) pout ethanol in to a test tube of water
4 if the solution contains lipids it will turn and cloudy colour

14

Definition Of denatured

Where the shape of the enzyme changes due to PH or temperature and the bonds in the enzyme are broken which mean the lock and key mechanism will no longer work as the lock has changed shape and denatured

15

How does the heart pump blood

1) blood flows into the atria from the vena cava and the pulmonary vein

2) the atria contracts, pushing blood into the ventricles

3)the ventricles contract forcing the blood into the pulmonary artery and the aorta and out of the heart

4) blood flows to the organs through arteries and returns through veins

5) the atria fills again and the whole cycle starts over

16

Arteries

Carry blood away from the heart

1) the heart pumps the blood out at a high pressure so the artery walks are strong And elastic

2) contains thick layers of muscle to make them stronger and elastic fibres to allow them so stretch and spring back

17

Capillaries

Involved in the exchange of materials at the tissues

1) arteries branch into capillaries
2) carry blood close to every cell in the body to exchange substances with them
3) permeable walls so substances can diffuse in and out
4) supply food and oxygen and take away waste (CO2)
5) walls are one cell thick - increase the rate of diffusion by decreasing the distance over which it occurs

18

Veins

1) capillaries join up to form veins
The blood is at a lower pressure in the veins so the walls don’t need to be thick

2) valves to keep the blood flowing in the right direction

19

Platelets

•Small fragments of cells
•No nucleus
•Help blood clot at a wound to stop you from bleeding and to stop microorganisms from getting in
•Lack of platelets can cause excessive bleeding and bruising

20

Artificial heart advantages

ADVANTAGES: less likely to be rejected by the body’s immune system and they are made from metals or plastics so the body doesn’t recognise them as foreign and attack like with a living tissue

21

How do Faulty heart valves occur

Valves can be damaged or weakened by heart attacks , infection, old age

22

Biological valves

Taken from humans or other mammals

23

Medical valves

Man made

24

Benign Tumour

•Where a tumour grows until there is no room

•Tumour stays in one place rather than invading other tissues in the body

•Not normally dangerous and tumour isn’t cancerous

25

Malignant tumour

•Where the tumour grows and spreads to neighbouring healthy tissues

•Cells can break off and spread to other parts of the body by traveling in the blood stream

•Invade healthy tissues anywhere in the body and form secondary tumours

•Dangerous and can be fatal , cancers

26

Risk factors of cancers associated with life style

•Smoking
•Obesity
•UV exposure
•Viral infection

27

What cancers is smoking linked to

•Lung cancer
•Mouth cancer
•Bowel cancer
•Stomach cancer
•Cervical cancer

28

What cancers are obesity linked to

•Bowel
•Liver
•And kidney cancer


( second biggest preventable cause of cancer after smoking )

29

What cancers are UV exposure linked to ? And who are at a higher risk?

•Skin cancer

•People in sunny climates , people who spend a lot of time outside and people who use sun beds are at a higher risk of getting skin cancer

30

What cancers are linked to viral infections

•Some viruses have been shown to increase the chance of developing certain types of cancer

•The chance of becoming infected is sometimes due to lifestyle- spread through unprotected sex or sharing needles

31

Risk factors of cancer through genetics

•Inherit faulty genes meaning you’re more susceptible to cancer

•Mutations in the BRCA genes have been linked to an increased likelihood of developing Breast and ovarian cancer

32

Epidermal tissue in the leaf

•Covers the whole plant

•covered with a waxy cuticle, which helps to reduce water loss by evaporation

33

Palisade mesophyll tissue in the leaf

•This is part of the leaf where most photosynthesis happens

• has Lots of chloroplasts , meaning that they’re near the top of the leaf where they ca get most light

34

Spongy mesophyll tissue in the leaf


Contains big air spaces to allow gases to diffuse in and out of cells

35

Xylem and phloem in the leaf

•Transports water, mineral ions and food Around the plant

a network of vascular bundles , which deliver water and other nutrients to the entire leaf and take away glucose produced by photosynthesis, help support the structure

36

Meristem tissue in the leaf

•Found at the growing tips of shoots and roots and is able to differentiate into lots of different types of plant cells allowing the plant to grow

•are adapted for efficient gas exchange

37

Structures of the tissues that make up the leaf

1. Epidermal tissues -
2.upper epidermis-
3.palisade layer-
4. Xylem and phloem-
5. Tissues -

38

Upper epidermis in leaf

is transparent so that light can pass through it to the palisade layer

39

Lower epidermis in leaf

Full of stomata which let CO2 diffuse directly into the leaf

40

Guard cells in the leaf

•Control the opening and closing of the stomata and adapter for gas exchange and controlling water loss in the leaf

•When the plant has lots of water the guard cells fill with it and go plump and turgid

•When the plant is short of water the guard cells lose water and become flaccid making the stomata close - stopping water vapour escaping

41

Air spaces in the leaf

The air spaces in the spongy mesophyll tissue increase the rate of diffusion of gases

42

Where is amylase enzymes made?

Salivary glands
Pancreas
Small intestine

43

What does amylase enzymes break down

Breaks down starch into maltose

44

Where is protease enzymes made

Stomach (pepsin)
Pancreas
Small intestine

45

What does protease enzymes break down

Breaks proteins down to amino acids

46

Where is lipase enzymes made

Pancreas
Small intestine

47

What do lipase enzymes break down

Breaks lipids down to glycerol or fatty acids

48

Bile

Produced in the liver
Stored in the gall bladder before being released into the small intestine

49

What does bile do

The hydrochloric acid in the stomach makes the ph too acidic for enzymes in the small intestine to work properly
Bile is alkaline so it neutralises the acid and makes conditions alkaline

Emulsifies fats , giving a much bigger surface area of fat for the enzyme lipase to work on making digestion faster

50

Alveoli

Carry’s out gas exchange in the body

51

How alveoli carry out gas exchange in the body

The Blood passing next to the alveoli has just returned to the lungs so it contains lots of carbon dioxide and very little oxygen
Oxygen diffuses out of the alveolus into the blood
CO2 diffuses out of the blood into the alveolus to be breathed out

52

Calculation of breathing rate in breaths per minute

Breaths per minute = number of breaths / number of minutes

53

Calculating rate of blood flow

Rate of blood flow = volume of blood / number of minutes

54

Communicable diseases

Can spread from person to person or between animals and people - contagious

55

Non communicable diseases

Cannot spread between organisms

Generally last for a long time and get worse slowly

56

Risk factors that cause disease directly

Smoking - cardiovascular disease, lung disease and lung cancer

Obesity- type 2 diabetes

Smoking when pregnant- cause lots of problems for the unborn baby - drinking alcohol has similar effects

Radiation- cancer can be caused by long exposure to radiation

57

Disadvantage of artificial heart

DISADVANTAGE: don’t work as well as healthy natural hearts , heart can wear out, electrical Motor could fail, blood doesn’t flow smoothly causing blood clots or strokes so patient has to take drugs to thin blood which can cause bleeding if they are hurt in an accident

58

What is an artificial heart

Mechanical devices that pump blood
Temporary

59

What can faulty heart valves damage


The damage can cause valve tissue to stiffen, so it won’t open properly, valve may become leaky, allowing blood to flow in both directions rather than forward - blood is not circulating properly

60

What is a catalyst

Is a substance which increases the speed of a reaction without being changed or used up in the reaction

61

What is an enzyme

•Are catalyst produced by living things
•Biological catalyst

62

Lock and key model of enzyme action

•Every enzyme has an active site with a unique shape that fits onto the substance
1. Substrate fits into the active site
2. Reaction occurs
3. The enzyme is unchanged but the substrate comes out as a product

63

What is an indices fit - lock and key model

When the active site changed shape a little as the substrate brings to it to get a tighter fit

64

Temperature affect on enzymes

• changing the temperature changes the rate of an enzyme catalysed reaction
• higher the temperature increases the rate but if it’s to hot some of bonds holding the enzyme together beak changing the active site and denaturing it

65

Ph affect on enzymes

• if it’s too high or too low it interferes with the bonds holding the enzyme together ,denaturing it
• normally the optimum ph is 7 (neutral)
However not always pepsin works best st ph2 (acidic)

66

Carbohydrases convert carbohydrates into simple sugars (amylase) what does it convert to

Starch —- amylase enzyme—> maltose

67

Where is amylase made

Salivary glands
Pancreas
Small intestine

68

Protease convert proteins into amino acids

Proteins — protease enzyme —> amino acids

69

Where is protease made

Stomach(pepsin)
Pancreas
Small intestine

70

Lipase convert Lipids into glycérol and fatty acids

Lipid — lipase enzyme —> glycerol and fatty acids

71

Where is lipases made

Pancreas
Small intestine

72

How does bile neutralise stomach acid ?

•Hydrochloric acid in the stomach makes the PH too acidic for enzymes in the small intestine to work properly. Bile is alkaline it neutralises the acid and makes conditions alkaline
•enzymes in the small intestine work better in alkaline conditions

73

How does bile neutralise emulsifies

Bile emulsifies fats
It breaks down fats into tiny droplets giving a much bigger surface area of fat for the enzyme lipase to work on making digestion faster

74

Thorax

1.Thorax is the top part of your body
2. It’s separated from the lower part of the body by the diaphragm

75

Alveoli carrying out gas exchange

1. The lungs contain millions of little air sacs called Alveoli surrounded by a network of blood capillaries. This is where gas exchange takes place
2. The blood passing next to the Alveoli has returned to the lungs so it contains CO2 - oxygen diffuses out of the Alveolus into the blood CO2 diffuses out of the blood into the alveolus to be breathed out
3. When the blood reaches body cells oxygen is released from RBCs and diffuses into the body cells
4. At the same time CO2 diffuses out of the body cells into the blood . Its then carried back to the lungs

76

Calculating the breathing rate in breathes per minute

Breathes per minute = number of breaths / numb of minutes

77

Double circulatory system

Two circuits
Right ventricle and left ventricle

78

What does the right ventricle do

Pumps deoxygenated blood to the lungs to take in oxygen
The blood then returns to the heart

79

What does the left ventricle do

Pumps oxygenated blood around all the other organs if the body
The blood gives up its oxygen at the body cells and the deoxygenated blood returns to the heart to be pumped out to the lungs again

80

How Heart contracts to pump blood around the body

1. Blood flows into the two atria from the vena cava and the pulmonary vein
2. The atria contract , pushing the blood into the ventricles
3. The ventricles contract , forcing the blood into the pulmonary artery and the aorta and out of the heart
4. The blood then flows to the organs through arteries and returns through veins
5. The atria fill gain and the whole cycle starts over

81

How does the heart get it’s own supply of oxygenated blood

Arteries called coronary arteries branch off the aorta and surfing the heart making sure that it gets all the oxygenated blood it needs

82

The Hearts Pace maker

•the resting heart rate is controlled by a group of cells in the right atrium wall that acts as a pacemaker
• these cells produce a small electric unlike which spread to the surrounding muscle cells causing them to contract

83

Arteries

Carry the blood away from the heart
•The heart pumps blood at a high pressure so the artery walls are strong and elastic
• the walls are thick compared to the size of the lumen
•they contain this layer of muscle to make them strong and elastic fibres to allow them to stretch and spring back
• branch Into capillaries

84

Capillaries

Involved in the exchange of materials at the tissues
• arteries branch into capillaries
• really tiny
• carry blood really close to every cell in the body to exchange substances with them
• permeable walls so substances can diffuse in and out
• they supply food and oxygen and take away waste
• walls are one cell thick which increases the rate of diffusion be decreasing the distance over which it occurs
• join up to make veins

85

Veins

Carry blood to the heart
• capillaries join up to form veins
• blood is at a Lower pressure in the veins so the walls aren’t as thick as arteries
• bigger lumen to help the blood flow despite lower pressure
• have valves to help keep blood flowing In The right direction

86

How can the arteries carry blood under pressure

•The heart pumps blood at a high pressure so the artery walls are strong and elastic
• the walls are thick compared to the size of the hole down the middle ( the lumen)
•they contain this layer of muscle to make them strong and elastic fibres to allow them to stretch and spring back

87

Calculate the race of blood flow

Rate of blood flow = volume of blood / number of minutes

87

What is the job of the red blood cell

To carry oxygen from the lungs to all the cells in the body

87

What is the structure of the red blood cell

•Is a shape of Biconcave disc which gives a large surface area for absorbing oxygen
• no nucleus allowing more room for oxygen
•Contains haemoglobin (red pigment)

87

What does haemoglobin(RBCs) do in the lungs

In the lungs haemoglobin binds oxygen to become oxyhaemoglobin

87

What does haemoglobin(RBCs) do in body tissues

The reverse of what happens in the lungs oxyhemoglobin splits into haemoglobin and oxygen to release oxygen to the cells

88

How do white blood cells defend against infection

• some change their shape to consume the pathogen the process is called phagocytosis
•others produce antibodies to fight microorganisms as well as antitoxins to neutralise any toxins produced by the microorganisms (pathogens)
• they do have a nucleus

89

What do platelets do


Clot blood at a wound
Stop microorganisms getting in
Lack of platelets e can cause excessive bleeding and bruising
Small fragments of cells
No nucleus

90

What does plasma do

Carries everything
RBCs ,WBCs
Glucose and amino acids
CO2
urea
Hormones proteins
Antibodies and antitoxins

91

What is coronary heart disease

Is when arteries that supply the blood to the muscle of the heart get blocked by layers of fatty material building up causing arteries to become narrow so blood flow is restricted and there’s a lack of oxygen to the heart

92

What are stents

They are tubes inserted inside arteries to keep them open making sure blood can pass through to the heart muscle keeping the persons heart beating

93

What do stents do

They lower the risk of a heart attack in people with coronary heart disease
They are effective for a long time and the receiver from surgery is quick

94

Risk of stents

•Risk of complications during the operation and a risk of infection from surgery
• risk of patients developing thrombosis-a blood clot near the stent

95

What is cholesterol and what happens when you have too much in your blood stream

•Is an essential lipid that your body produces and needs to function properly
•Cause fatty deposits to form inside arteries which can lead to coronary heart disease

96

How do stations reduce cholesterol in the blood

Are a drug that can reduce the amount of bad cholesterol ( LDL cholesterol)present in he bloodstream slowing down the rate of fatty deposits forming

97

Advantages of statins

• by reducing the bad cholesterol in the blood it reduces the risk of strokes , CHD and heart attacks
• reducing bad cholesterol can increase the amount of a beneficial type of cholesterol (HDL cholesterol)
Which can remove LDL cholesterol
• statins may also help prevent other diseases

98

Disadvantage of statins

• are a long term drug that must be taken regularly - risk of forgetting
• can cause negative side effects - headaches , kidney failure , liver damage and memory loss
• the effect is statins isn’t instant

99

What is an artificial heart

Mechanical devise that pumps blood for a person whose own heart has failed

100

What is artificial blood

Replaces the lost volume of blood to give the patient enough time to produce new blood cells or get a blood transfusion

101

What is a communicable disease caused by


Caused by bacteria, viruses, parasites and fungi

102

What can smoking do to your health

Cardiovascular disease
Lung disease
Lung cancer
It also damages the walls of arteries and the cells in the lining of the lungs
When pregnant it can cause health problems for the baby

103

What can obesity do to your health

Type 2 diabetes making you less sensitive or resistant to insulin meaning you struggle to control the concentration of glucose in the blood

104

What does drinking too much do to your health

Liver disease
Affects brain function by damaging the nerve cells in the breaks causing the brain to lose volume

105

What can too much UV exposure cause

Uv radiation increase the chance of skin cancer

106

How can viral infection affect your health

Some virus are shown to increase the chances of developing certain cancer e.g. hepatitis B and C can increase the risk of liver cancer

107

What are phloem tubes

Tubes made of columns of elongated living cells with small pores in the end walls to allow cell sap to flow through

108

What do phloem tubes do

A process called translocation where the tube transports food substances in both directions which was made in the leaves to the rest of the plant for immediate use or for storage

109

What are xylem tubes

Tubes made of dead cells joined end to end with no end walls between them and a hole down the middle
Strengthened by lignin

110

What do xylem tubes do

Transpiration stream which Carry’s water and mineral ions from the roots to the stem and leaves

111

What is transpiration and what causes it

•It’s the loss of water from the plant
•It’s caused by the evaporation and diffusion of water from a plants surface
•The evaporation Creates a shortage Of water in the leaf so more water is drawn up from the plant rejoint the xylem vessels to replace it
•More water is being drawn up from the roots and there’s constant transpiration steam of water through the plant

112

What is transpiration rate affected by

Light intensity
Temperature
Air flow
Humidity

113

How does light intensity affect the transpiration rate

•The brighter the light the greater the transpiration rate
• the darker it gets the stomata begins to close letting very little water out and photosynthesis can’t happen in the dark so they don’t need to be open to CO2 in

114

How does temperature affect the transpiration rate

The warmer it is the faster transportation happens as the water particles the more energy to evaporate and diffuse out of the stomata

115

How does air flow affect the transpiration rate

•The better the air flow around the leaf the greater transpiration rate as the water vapour is swept away maintaining a low concentration of water in the air outside of the leaf and the diffusion happens quickly
•If the flow is poor the water vapour surrounds the leaf and doesn’t move away meaning there’s high concentration of water particles so diffusion doesn’t work as quickly

116

How does humidity affect the transpiration rate

•The drier the air the faster transpiration happens
•And If its humid there is a lot of water so there’s not much of a difference between the inside and outside of the leaf and diffusion works fastest in high concentration to low concentration

117

Why do you find more stomata on the underside of the leaf

The lower surface is shaders and cooler to less water is lost through the stomata the the upper surface as the guard cells close more in darker places

118

What are guard cells adapted for

Gas exchange and controlling water loss in a leaf