Biology B1-B4 Flashcards
(118 cards)
1
Q
What equipment do we use to see things too small for our eyes?
A
Microscope
2
Q
What are the three main steps to follow when looking at something through a microscope?
A
- Start with the lowest magnification objective lens
- Focus using the focus wheels
- Increase magnification (if you need to)
3
Q
What happens to an image when we focus a microscope?
A
The image becomes sharp enough to see (clearer)
4
Q
What is an organism?
A
A living thing
5
Q
What is a unicellular organism?
A
An organism made of only one cell
6
Q
What is a multicellular organism?
A
An organism made of more than one cell
7
Q
What is a cell?
A
The basic building block of all life
8
Q
What is sub-cellular structure?
A
A small part of a cell with a specific function (job)
9
Q
Name four sub-cellular structures found in all cells.
A
Cell membrane, cytoplasm, genetic material and ribosomes
10
Q
Name five sub-cellular structures found in animal cells.
A
Cell membrane, cytoplasm, ribosomes, mitochondria, nucleus
11
Q
Name eight sub-cellular structures found in plant cells.
A
Cell membrane, cytoplasm, ribosomes, mitochondria, nucleus, chloroplasts, cell wall, vacuole
12
Q
What is the function of the nucleus?
A
To control the activities of the cell/contains the DNA
13
Q
What is the function of the cell membrane?
A
To control what substances enter and leave the cell
14
Q
What is the function of the cytoplasm?
A
To allow chemical reaction to take place
15
Q
What is the function of the mitochondria?
A
To allow respiration to take place
16
Q
What is the function of the ribosomes?
A
To allow proteins to be made
17
Q
What is the function of the cell wall?
A
To support the cell
18
Q
What is the function of the vacuole?
A
To keep the cell rigid
19
Q
What is the function of the chloroplasts?
A
To allow photosynthesis to take place
20
Q
What word do we use to describe how much bigger microscopes make things look?
A
Magnification
21
Q
What word do we use to describe how big something really is?
A
Actual size
22
Q
What word do we use to describe how big something looks through a microscope?
A
Image size
23
Q
What is the equation for working out image size?
A
Image size = actual size x magnification
24
Q
What is the difference between magnification and focus?
A
Magnification make the image appear bigger; focus makes the image clearer
25
Name six common sub-cellular structures found in bacterial cells.
Cell membrane, cell wall, genetic material, ribosomes, slime capsule, flagellum
26
In bacteria, what is the function of the flagellum?
To allow the cell to move
27
Name six common sub-cellular structures found in yeast cells.
Cell membrane, cell wall, cytoplasm, nucleus, ribosomes, vacuole
28
What is diffusion
The movement of a substance from an area of high concentration to an area of low concentration
29
In cells, what two factors affect the rate of diffusion?
Temperature, cell surface area
30
How does temperature affect the rate of diffusion?
As temperate increases, the rate of diffusion increases
31
How does cell surface area affect the rate of diffusion?
As cell surface area increases, the rate of diffusion increases
32
Name two specialised animal cells.
Red blood cell, muscle cell (other examples: sperm cell, nerve cell, ciliated cell, white blood cell)
33
What is the function of a red blood cell?
To carry oxygen around the body
34
Give two adaptations of a red blood cell.
No nucleus, biconcave shape
35
Give two reasons why a red blood cell has a biconcave shape.
Easier to move through blood vessels; increases the surface area
36
What is the function of a muscle cell?
Contracts and moves things (e.g. bones, food)
37
Give one adaptation of a muscle cell.
Many mitochondria for energy to contract
38
Give two examples of specialised cell in plants.
Root hair cell, palisade cell
39
What is the function of a root hair cell?
To absorb water (and nutrients) from the soil
40
Give two ways in which a root hair cell is specialised for its function.
Large extension, no chloroplasts
41
What is the function of a palisade cell?
To carry out a lot of photosynthesis
42
Give one way in which a palisade cell is specialised to it function.
Many chloroplasts
43
What are the four function of the skeleton?
Support for the body, movement, protection of vital organs, making and storage of blood cells
44
In the skeleton, what is a joint?
Where two bones meet
45
What is a ligament?
Tissue that connects bone to bone
46
Why are bones covered by cartilage?
To stop them rubbing together
47
What is the function of the synovial fluid?
To reduce friction when bones move within a joint
48
What is a muscle?
Tissue that contracts and relaxes
49
What is then function of muscles?
To bring about movement
50
Name three main types of muscle.
Smooth, cardiac and skeletal muscle
51
Where is smooth muscle found in the body?
Wall of hollow organs (e.g. intestines, stomach)
52
Where is cardiac muscle found in the body?
Heart
53
Where is skeletal muscle found in the body?
Covers the skeleton
54
What is a tendon?
Tissue that connects muscle to bone
55
What name antagonistic muscles?
Muscle pairs that oppose the action of each other
56
Name an example of a pair of antagonistic muscles.
Biceps and triceps
57
What do muscles do to bones when they contract?
Exert a force of the bones
58
What is the function of a nerve cell?
To send electrical signals around the body
59
How is a nerve cell adapted to its function?
Long cell body (axon); lots of connections to other cells (dendrites)
60
What is a tissue?
A group of similar cells working together
61
What is an organ?
A group of different tissues working together
62
What is an organ system?
A group of different organs working together
63
Name two organ systems.
Digestive system, respiratory system (other examples: reproductive, nervous, circulatory)
64
Which specialised cells make up nervous tissues?
Nerve cells
65
Name seven major components of a healthy human diet.
Carbohydrates, fats and oils, proteins, vitamins, minerals, fibre and water
66
Why do we need carbohydrates in our diet?
To provide energy
67
Why do we need fats and oils in our diet?
For energy storage and insulation
68
Why do we need proteins in our diet?
For growth and repair of cells and tissues
69
Why do we need vitamins in our diet?
Important for body processes and general health
70
Why do we need minerals in our diet?
Heeded to make blood, bones, etc.
71
Why do we need fibre in our diet?
Bulks up food to allow it to pass easily through the digestive system
72
Why do we need water in our diet?
For chemical reactions and transporting substances
73
Name two major factors that affect our energy requirements.
Age and amount of exercise done
74
What is a deficiency disease?
A disease caused by lacking a component of a healthy diet
75
What does underweight mean?
A diet in which less energy is taken in than is used by the body
76
What are the symptoms of being underweight?
Tiredness, headaches, dry skin and teeth problems
77
What is obesity?
A disease in which a person has a lot of body fat
78
What is the cause of obesity?
A diet in which more energy is taken in than is used by the body
79
Name three effects of obesity.
Increased risk of type 2 diabetes, heart disease and cancer
80
What is anaemia?
When a person does not make enough red blood cells
81
What is the cause of anaemia?
Lack of iron
82
What are the symptoms of anaemia?
Tiredness, lack of energy and shortness of breath
83
What is the function of the mouth?
Breaks down food into smaller pieces
84
What is an enzyme?
A protein that speeds up chemical reactions
85
What is the function of saliva?
Contains enzymes that break down carbohydrates and softens food
86
What is the function of the stomach?
Churns food; contains stomach acid and enzymes that break down food further
87
What is the roles of stomach acid?
Kills bacteria in food
88
What is the function of the pancreas?
Produces digestive enzymes
89
What is the function of the small intestine?
Digests and absorbs nutrients into the bloodstream
90
What is the purpose of the villi and microvilli in the small intestine?
Increase the internal surface area for greater absorption
91
Where is bile produced?
Liver
92
What is the function of the large intestine?
Absorbs water from digested food back into the body
93
What are the functions of the gut bacteria?
To digest some carbohydrates, reduce the chance of harmful bacteria causing disease and provide vitamins B and K
94
How do gut bacteria protect against harmful bacteria?
By competing with them
95
Why are some bacteria harmful to humans?
They release toxins
96
What is the respiratory system?
A system that allows air to pass in and out of the body
97
In the respiratory system what is ventilation?
The movement of gases into and out of the lungs
98
What happens to the intercostal muscles and rib cage when we breathe in?
Intercostal muscles contract and rib cage expands
99
What happens to the diaphragm when we breathe in?
Diaphragm contracts and flattens
100
What happens to lung pressure when we breathe in?
Lung pressure decreases
101
What happens to the intercostal muscles and rib cage when we breathe out?
Intercostal muscles relax and rib cage drops inwards
102
What happens to the diaphragm when we breathe out?
Diaphragm relaxes and moves up
103
What happens to lung pressure when we breathe out?
Lung pressure increases
104
What is the function of the goblet cells in the trachea?
To release mucus into the trachea
105
What is the function of the mucus in the trachea?
To trap dust and bacteria
106
What is the function of the ciliated epithelial cells in the trachea?
To sweep mucus up and out of the trachea
107
Where does gas exchange take place in the lungs?
Alveoli
108
Which gas diffuses from the alveoli into the bloodstream?
Oxygen
109
Which gas diffuses from the bloodstream into the alveoli?
Carbon dioxide
110
Name four ways in which alveoli are adapted for gas exchange.
Good blood supply, membrane is one cell thick, large surface area, moist surface
111
What happens to a person’s breathing rate when they exercise?
Increases
112
What is asthma?
When the lining of the airways from the mouth to the lungs becomes irritated and swells up
113
What are the symptoms of asthma?
Coughing wheezing, chest tightness and shortness of breath
114
What happens during an asthma attack?
The airways leading to the lugs become narrower, more inflamed and congested with mucus
115
What can trigger and asthma attack?
Pollen, pathogens, pet hair and cigarette smoke
116
What effect does smoking have on the bronchi?
Irritates them, leading to lung disease
117
What effect does smoking have on the alveoli?
Reduces their surface area, so less gas exchange takes place
118
What is the effect of tar in cigarette smoke?
Can cause mouth, throat or lung cancer
