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Flashcards in Unit 2 Deck (116)
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1
Q

Cells group together to form what?

A

Tissues

2
Q

Tissues form what?

A

Organs

3
Q

How to stem cells reproduce?

A

Through mitosis

4
Q

What is the function of an adult stem cell?

A

To repair and replace damaged cells

5
Q

Where does growth in plants take place?

A

Meristems

6
Q

Where are meristems found in plants?

A

Tips of growing shoots and roots

7
Q

Where is an apical meristem found?

A

Root tips

8
Q

Where are lateral meristems found?

A

Surrounds stem of plant

9
Q

What does the central nervous system consist of?

A

The brain and spinal cord

10
Q

What are some of the main functions of the nervous system?

A

Send information, co ordinate workings of internal organs, respond to stimuli on the outside

11
Q

What is the role of the sensory receptors?

A

To send information about what is happening inside and out to the CNS

12
Q

What is the role of the cerebrum in the brain?

A

Enables conscious thought and memory

13
Q

What is the role of the cerebellum in the brain?

A

Controls coordination and balance

14
Q

What is the role of the medulla in the brain?

A

Controls breathing and heart rate

15
Q

What is a reflex?

A

An unconscious action such as pulling away from a hot object

16
Q

What is your reflex arc?

A

A simple pathway for the reflex action and is made up of three neurons

17
Q

What are the three neurons that makes up the reflex arc?

A

Sensory neuron, reflex neuron and motor neuron

18
Q

What is the role of the sensory neuron?

A

It carries information from a receptor to a relay neuron

19
Q

What is the role of a relay neuron?

A

It connects a sensory neuron to a motor neuron

20
Q

What is the job of a motor neuron?

A

Carries information to an effector (a muscle or gland)

21
Q

What are the gaps between neurons called?

A

Synapses

22
Q

Has the exocrine system got a faster or slower response compared to the nervous system?

A

Slower

23
Q

What is controlled by the endocrine system?

A

Hormonal control

24
Q

In the endocrine system, what releases hormones into the blood stream?

A

Endocrine glands

25
Q

What is the name of cells sensitive to hormones?

A

Target tissues

26
Q

What molecule is the only source of energy for brain cells?

A

Glucose

27
Q

What is the definition of multicellular?

A

An organism made up of many cells

28
Q

After eating is the level of glucose high or low?

A

High

29
Q

What is excess glucose stored in the form of and where?

A

Glycogen in the liver

30
Q

What helps to promote the conversion of glucose to glycogen?

A

Insulin produced in the pancreas

31
Q

The hormone glucagon helps to convert what substance?

A

Glycogen back into glucose

32
Q

What causes diabetes?

A

When someone unable to control blood sugar levels dues to problems producing insulin

33
Q

What does diploid mean?

A

A cell that has a double set of chromosomes

34
Q

What does haploid mean?

A

A cell that has a single set of chromosomes

35
Q

What are gametes and where are the produced?

A

Sex cells, produced in structures called gonads

36
Q

Where is sperm produced?

A

In the testes

37
Q

What is produced in the ovaries?

A

Eggs or ova

38
Q

What is fertilisation?

A

When a male and female gamete fuse to form a zygote

39
Q

Where does fertilisation in animals take place?

A

In the oviduct

40
Q

In plants, what is the female gamete called and where is it produced?

A

Ovules, produced in the ovary

41
Q

In plants, what is the male gamete and where is it produced?

A

Pollen grains, formed in the anther

42
Q

To reach the ovule, what does the pollen grain have to grow?

A

A pollen tube

43
Q

Where does fertilisation happen in plants?

A

Inside the ovule

44
Q

What is pollination?

A

The transfer of pollen in plants

45
Q

What is variation?

A

Differences within the same species

46
Q

What is discrete variation?

A

When feature can be divided into two or more groups (eg - eye colour)

47
Q

What is continuous variation?

A

When a feature has a wide range of values (eg - height)

48
Q

What is the definition of polygenic?

A

When something is controlled by more than one gene (continuous variation is polygenic)

49
Q

What is the definition of monogenic?

A

When something is controlled by only one gene (discrete variation)

50
Q

What is phenotype?

A

The physical appearance of an organism

51
Q

What is a way of recoding patterns in inheritance?

A

A family tree

52
Q

What is albinism?

A

A condition that results in a lack of skin pigmentation

53
Q

What is genetic counselling?

A

When people get advice from family trees

54
Q

What is inheritance?

A

How characteristics are passed on from one generation to another

55
Q

What are characteristics controlled by?

A

Genes

56
Q

Genes can exist in different forms called what?

A

Alleles

57
Q

What does dominant mean?

A

When one gene masks the other

58
Q

What is homozygous?

A

Two same forms of a gene (BB)

59
Q

What is heterozygous?

A

When it is two different forms of a gene (Bb)

60
Q

What is meant by genotype?

A

Genetic characteristics of an organism

61
Q

What is the transpiration stream?

A

The movement of water from the roots to the leaves

62
Q

What is transpiration?

A

The loss of water by evaporation

63
Q

Where does transpiration take place?

A

Through openings in the leaves called stomata

64
Q

What controls the opening and closing of stomata?

A

Guard cells

65
Q

Where are stomata found?

A

On the surface layers of the leaf or upper and lower epidermis

66
Q

What is the upper epidermis covered in?

A

A waxy layer called the cuticle

67
Q

What does the cuticle layer on a leaf help to do?

A

Cut down on water loss

68
Q

What does the palisade layer consist of?

A

Tall cylindrically-shaped cells packed with chloroplasts

69
Q

What is the spongy mesophyll layer of a leaf?

A

Layers of green cells which take in CO2 and gives out oxygen during photosynthesis

70
Q

Water enters the leaf by what process and where?

A

Osmosis through root hair cells

71
Q

What is the role of the xylem in a plant?

A

Helps to transport water up the plant

72
Q

What does the xylem contain to support the plant?

A

Lignin

73
Q

What is role of the phloem in a plant?

A

Transports sugar and other nutrients to all parts of the plant

74
Q

Is energy needed to drive transpiration?

A

No only sunlight

75
Q

Why can’t organisms carry out diffusion?

A

As it gets bigger, surface area to volume ration gets smaller

76
Q

What is the circulatory system?

A

Blood transports nutrients and oxygen to body and removes CO2

77
Q

What makes up the circulatory system?

A

Heart and vessels

78
Q

How many chambers are in the heart?

A

Four

79
Q

What are the two upper chamber of the heart called?

A

Atria

80
Q

What are the two lower chamber of the heart called?

A

Ventricles

81
Q

Which chambers of the heart receives blood?

A

Atria

82
Q

Which chambers of the heart discharge blood?

A

Ventricles

83
Q

What to valves do?

A

Ensure there is no back flow of blood

84
Q

Blood flows into the heart through what?

A

Veins

85
Q

Blood flows out of the heart through what?

A

Arteries

86
Q

What are capillaries?

A

Very thin, connects arteries and veins, large surface area for diffusion

87
Q

What is blood made up of?

A

Red blood cells, white blood cells, plasma and platelets

88
Q

What feature helps the red blood cell do its job?

A

Bi-concave in shape, no nucleus. Extra space to carry oxygen

89
Q

What is haemoglobin?

A

A carrier molecule that’s combines oxygen in the lungs

90
Q

What does the white blood cells do?

A

Helps to fight infections

91
Q

What does plasma in the blood do?

A

Dissolves CO2

92
Q

What do platelets in the blood do?

A

Helps to clot blood

93
Q

What takes place in the lungs?

A

The exchange of oxygen and CO2

94
Q

What lines the trachea and why?

A

Cilia, moves germs and dirt up and out of the lungs

95
Q

What helps to keep the trachea open?

A

Incomplete rings of cartilage

96
Q

What is mucus and what is its role?

A

A sticky substance that traps dust and germs

97
Q

What is at the end of the bronchioles?

A

Alveoli

98
Q

What takes place in the alveoli?

A

Where gas exchange takes place, thin walled and huge surface area

99
Q

Blood flows through the lungs through what?

A

Capillaries

100
Q

How is air moved in and out of the lungs?

A

The diaphragm contracting

101
Q

Why is food broken down in the mouth?

A

To expose a larger surface area for enzymes to act on

102
Q

What is the oesophagus?

A

A tube to the stomach

103
Q

What movement helps to push food down the oesophagus?

A

Waves of peristalsis

104
Q

What is in saliva to help break down starch into maltose?

A

Amylase

105
Q

What does the liver do?

A

Removes toxins and produces bile

106
Q

Which body part absorbs nutrients in food?

A

Small intestines

107
Q

What is the role of the large intestine?

A

Removes water from fecal matter

108
Q

What is the lining of the small intestine covered in?

A

Villi

109
Q

Why is the villi in the lining of the small intestine?

A

Increases surface area for absorption

110
Q

What is in the centre of each villus and what does it do?

A

A lacteal, absorbs end products which are fatty acids and glycerol

111
Q

What is the name of the fluid that connects the lacteal with the secondary transport system?

A

Lymph

112
Q

What does nicotine do the human body?

A

Causes arteries to narrow. Increases blood pressure

113
Q

Name two lung diseases caused by smoking

A

Bronchitis and emphysema

114
Q

What disease will result if a person is iron deficient?

A

Anaemia

115
Q

Why are fat rich diets bad for the human body?

A

It can create deposits in blood vessels which can restrict blood flow

116
Q

What organs can long term use of alcohol damage?

A

Liver, stomach and kidneys