Topic 2- Organisation Flashcards Preview

GCSE Biology 2017-2018 > Topic 2- Organisation > Flashcards

Flashcards in Topic 2- Organisation Deck (124):
1

What type of cells form tissues?

Specialised cells

2

When does differentiation occur

During the development of a multi cellular organism

3

What is the purpose of glands in the digestive system?

It is found in the pancreas and salivary glands, produces digestive juices

4

Definition of organ

A group of tissues that work together to perform a certain function

5

Definition of enzymes

Biological catalysts

6

Definition of catalyst

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

7

What are enzymes made of?

Proteins, and all proteins are made of chains of amino acids

8

What does every enzyme have?

An active site with a unique shape that fits onto the substance involved in a reaction

9

Name of the diagram that shows enzyme action

"Lock and key" model

10

How is the lock and key different to the reality and what is it called

In reality, the active site changes shape a little as the substrate binds to get a tighter fit and it is called induced fit

11

2 things that affect enzymes

Temperature and pH

12

What happens to an enzyme when the temperature is too high?

Some of the bonds holding the enzyme together break, and this changes the shape of the active site, so the substance won't fit. It is said to be DENATURED.

13

What is the use of pepsin enzyme in the stomach

It is used to break down proteins in the stomach

14

Optimum pH of pepsin?

pH 2

15

What does the enzyme amylase catalyse?

It catalyses the breakdown of starch to maltose.

16

What will the colour of iodine solution be, when starch is present?

Blue black

17

Describe the practical for how pH affects amylase activity

A drop of iodine solution in each spotting tile. Heat water in beaker until 35°c. In a test tube, add 1 cm^3 of buffer solution with pH 5 and 1 cm^3 of amylase solution and wait 5 mins. Then add 5 cm^3 of starch solution,mix and start clock. Every 30 secs, add a drop, when the iodine solution remains browny orange, starch is no longer present. Repeat with different pH buffer solutions to see how pH affects time.

18

What is the meaning of rate?

Rate is a measure of how much something changes over time.

19

Formula to work out the rate

Rate = 1000
--------
time

20

Why do starch, proteins and fats have to be broken down?

Because they are big molecules. They are too big to pass through walls of the digestive system, smaller molecules are easier to absorb into bloodstream.

21

Protease breaks down _ _ _ _ _ _ _ _ into _ _ _ _ _ _ _ _ _ _ _

Proteins into amino acids

22

All three enzymes are found in?

Small intestines and pancreas

23

What is another name for protease in the stomach?

Pepsin

24

What is starch broken down i)by ii)into?

i) amylase ii) maltose

25

An example of carbohydrase?

Amylase

26

Where are lipases found?

In the pancreas and small intestines.

27

Where is amylase found where the other enzymes aren't?

Salivary glands.

28

Example of other sugars apart from maltose

Dextrins

29

What are lipids?

Fats and oils

30

Where is bile produced?

In the liver

31

Where is bile released into

Small intestines.

32

What does bile do in the small intestines

HCl in the stomach is too acidic. Bile is alkaline. Enzymes in small intestines work best in akaline conditions.

33

What does bile do?

It emulsifiers fat, meaning it breaks down the fat into tiny droplets, increasing the surface area of fat for enzymes to work on, making digestion faster.

34

What is the purpose of HCl in the stomach?

To kill bacteria and to give right pH for protease enzyme to work

35

4 things you must do to prepare a food sample.

Break up food using pestle and mortar
Transfer food to beaker and add water
Stir mixture with glass rod to dissolve food
Filter solution using filter paper to get rid of solid bits of food.

36

What is the name of the test for sugar

Benedict's test

37

Describe the test for sugar

Prepare food sample and transfer 5 cm^3 to test tube and set water bath to 75°c. Add Benedict's solution (10 drops) to test tube and leave in bath for 5 mins. If reducing sugar is present, the colour will change from blue to green, yellow or brick red.

38

Test for starch

Make food sample and transfer 5 cm^3 to test tube. Add iodine solution and shake to mix. Solution will change from brown orange to black or blue black

39

Test for proteins

Prepare sample and transfer 2cm^3 to test tube. Add 2 cm^3 of Buiret solution to sample and shake to mix. If protein present, colour will change from blue to pink or purple.

40

Test for lipids

Prepare sample and transfer 5 cm^3 to test tube. Add 3 drops of Sudan III stain solution and shake to mix. If lipids present, it will separate to top layer bright red.

41

What is the thorax?

The top part of your body

42

How is the top part of your body separated from the lower part?

The diaphragm

43

What are the lungs surrounded by?

Pleural membranes

44

Where does gas exchange take place?

Small bags at the end of bronchioles called alveoli

45

Diffusion in alveoli

Oxygen diffuses out of the alveoli into blood and CO^2 diffuses out of blood into alveoli.

46

Red blood cells action after gas exchange

Red blood cells release oxygen and diffuses into body cells and body cells release CO^2 which diffuses into blood and carried back to lungs.

47

Formula to calculate breathing rate.

Breaths per minute= number of breathes
---------------------
Number of minutes

48

Describe the double circulatory system

The right side of the heart pumps deoxygenated blood to the lungs and returns with oxygen to the heart.
The left side of the heart pumps oxygenated blood to the rest of the body and returns with deoxygenated blood.

49

What is the walls of the heart mostly made of?

Muscular tissue

50

What do valves in the heart do?

They make sure blood flows in the right direction, preventing it from flowing backwards.

51

How many chamber are there in the heart and what are they called?

Right atrium, right ventricle, left atrium, left ventricle

52

What is the equivalent of the pulmonary vein called on the right side?

Vena cava

53

What do the atria do when blood flows into them?

They contract, pushing blood into ventricles.

54

What is the equivalent of the pulmonary artery called on the left side?

Aorta

55

What do the ventricles do when blood flows in?

They contract pushing blood through the pulmonary artery and aorta, out of the heart.

56

The blood flows through _ _ _ _ _ _ _ _ and returns through _ _ _ _ _ .

Flows through arteries and returns through veins

57

What are the coronary arteries?

They branch off the aorta supply the heart with its own oxygenated blood supply

58

What is your heart rate controlled by?

A group of cells in the right atrium wall

59

What do the group of "pacemaker" cells do?

They produce a small electrical impulse which spreads to surrounding muscle cells causing them to contract.

60

What is done if the patient has irregular heartbeat?

An artificial pacemaker is implanted under the skin and has a wire going to heart.

61

What do veins do?

Carry blood to the heart

62

What do capillaries do?

Involved in material exchanges at tissues

63

What do arteries do?

Carry blood away from heart

64

2 features of artery walls

Strong and elastic

65

What is the name of the hole in the middle of an artery

Lumen

66

How are the arteries strong and elastic?

They contain a thick layer of muscle for strength and have elastic fibres to allow them to stretch.

67

A features of arteries

They carry blood under high pressure

68

How are the walls of capillaries adapted for diffusion

They have permeable walls and it is also one cell thick, which decreases the diffusion distance

69

How are arteries, capillaries and veins connected?

Arteries branch into capillaries and capillaries eventually join up to form veins

70

Is the blood pressure high or low in the veins?

Low, so the walls don't need to be as thick as arteries

71

How do the veins keep the blood flowing in one direction

They have valves

72

Do veins have bigger or smaller lumen than arteries?

Bigger because the walls are thinner

73

Formula to calculate rate of blood flow?

Rate of blood flow= volume of blood flow
----------------------
Number of minutes

74

What is the shape of red blood cells?

Biconcave

75

What is the name given to haemoglobin binded with oxygen in the lungs?

Oxyhaemoglobin

76

What are red blood cells like in people who live in high altitude?

There is less oxygen in the air so they produce more red blood cells

77

What do white blood cells have that red blood cells don't?

A nucleus

78

What are platelets?

They are fragments of cells, which have no nucleus.

79

How do platelets help?

They help blood clot at a wound to stop blood loss and microbes entering.

80

Name 8 things that plasma carries

Red and white blood cells and platelets.
Nutrients (glucose and amino acids)
CO^2 - organs to lungs
Urea- liver to kidneys
Hormones
Proteins
Antibodies
Antitoxins

81

What is coronary heart disease?

It is when coronary arteries get blocked by layer fatty material building up. This causes passage to become narrow, so blood flow is restricted and lack of oxygen to heart muscle, resulting in a heart attack

82

How do stents work?

They keep the passages open, making sure blood passes to heart muscles, by pushing wall out.

83

2 advantages of stents

Thy are effective, and recovery time is quick

84

2 disadvantages of stents

Risk of complications and risk of infection

85

Definition of thrombosis

Risk of patients developing a blood clot near stent

86

What could cause coronary heart disease

Too much bad cholesterol which can cause fatty deposits

87

What are statins

Drugs that reduce amount of bad cholesterol present in blood.

88

3 advantages of statins

Reduce risks of strokes, coronary heart disease and heart attacks
Increase amount of good cholesterol, which can remove bad cholesterol
May prevent other diseases

89

3 disadvantages of statins

Long term drugs, must be taken regularly, could forget
Negative side effects (headaches, kidney failure, memory loss)
Isn't instant, takes time for effect

90

What are artificial hearts?

Mechanical devices that pump blood for a person whose own heart has failed.

91

Are artificial hearts permanent or temporary?

Most cases, temporary until donor heart can be found or to allow heart to rest or heal, but some cases, permanent

92

Advantage of artificial hearts

Less likely to be rejected. Made from metals or plastics, so not recognised as "foreign"

93

Disadvantages of artificial hearts

Don't work as well as natural ones, electrical motor could fail
Blood doesn't flow as smoothly could cause clots and strokes.
Patient has to take drugs to thin blood, could cause problems when hurt

94

3 ways that could cause heart valves to be damaged

Heart attacks, infection or old age.

95

Describe how a faulty heart valve could lead to poor blood circulation

Could stiffen, so it won't open properly
Could become leaky and blood flow could be both directions

96

How can valve damage be fixed?

Valve replacement from humans or mammals (cows or pigs) which are biological valves or man made which are mechanical valves

97

What is artificial blood?

It is a blood substitute and it may give the patient enough time to produce new blood cells.

98

Definition of health

Health is a state of physical and mental wellbeing.

99

4 things that cause communicable diseases?

Bacteria, virus, protists and fungi

100

3 factors that affect health

Balanced diet
Stress level
Life situations (access to medicine or healthy food)

101

What are risk factors

Things that are linked to an increase in the likelihood that a person will develop a certain disease during their lifetime

102

Types of risk factors

A person's lifestyle
Presence of a certain substance in the environment
Substance in your body

103

Some risk factors that directly cause a disease

Smoking- cardiovascular disease, lung disease and lung cancer
Obesity- type 2 diabetes
Smoking when pregnant- health problems for unborn baby
Cancer- exposure to certain substances or radiation

104

Things that cause cancer are known as what?

Carcinogens

105

3 things to do with the financial side of non communicable diseases

Cost of NHS research and treatment is huge
Families having to move for treatment is also costly
If someone dies, reduction in income and affects country's economy

106

What results to the formation of tumours?

Uncontrolled growth and division of cells and results in tumour

107

Definition of tumour

A mass of cells

108

Definition of benign

Tumour grows until there's no room, and it stays in one place. Isn't normally dangerous and isn't cancerous

109

Definition of malignant

Tumour grows and spreads. Cells can break off and travel to other parts of the body. Can form secondary tumours. Dangerous and can be fatal, cancers

110

5 risk factors for cancer

Smoking
Obesity
UV exposure (sun beds, hot climate)
Viral infection
Genes

111

Where does most photosynthesis happen in a plant?

Palisade mesophyll tissue

112

Where and why are there air spaces in a leaf?

In the spongy mesophyll tissue for gases to diffuse in and out of cells

113

What is the meristem?

It is found at the growing tips of shoots and roots and is able to change into lots of different types of plant cells.

114

How is the lower epidermis adapted for gas exchange?

Full of little holes called stomata which let CO^2 diffuse directly into leaf

115

What does the phloem transport?

Food substances made in leaves to rest of plants for use or storage.

116

What are phloem tubes like?

Made of columns of living cells with small pores at the ends to allow cell sap.

117

Definition of translocation

Transportation of food substances from leaves to the rest of plant

118

What are xylem tubes like?

Made of dead cells joined end to end with no walls between them.

119

What do xylem tubes transport?

Water and mineral ions from roots to stem and leaves.

120

Definition of transpiration stream

Movement of water from roots through xylem and out of the leaf.

121

Definition of transpiration

Evaporation and diffusion of water from a plant's surface (mostly at leaves)

122

4 main things that affect that transpiration rate

Light intensity- stomata closes as it darkens. Stomata closed means less water escape
Temperature- the warmer,the faster. Warm,more energy, diffuse out.
Air flow- good airflow means water vapour is swept away main into the lower concentration outside, so diffusion rate increases
Humidity- drier the air, faster transpiration. Air is humid means lots water already, not much difference

123

Why are there normally more stomata on the underside of leaves than the top?

The lower surface is shaded and cooler, so less water is lost

124

What 2 things are guard cells adapted for?

Gas exchange and controlling water loss