Biology paper 1 b1-5 Flashcards
1
Q
Define a cell
A
The basic unit of living things
2
Q
Name five organelles found in animal and plant cells
A
Nucleus, cytoplasm, cell membrane, ribosome, mitochondria.
3
Q
Name the three organelles only found in plant cells
A
Cell wall, chloroplasts, vacuole.
4
Q
Define a eukaryotic cell
A
A cell with a true nucleus.
5
Q
Define a prokaryotic cell
A
A cell without a true nucleus.
6
Q
Give the function of the nucleus
A
Controls all activities of the cell.
7
Q
Give the function of the mitochondria
A
Does aerobic respiration which produces energy.
8
Q
Give the function of the ribosomes
A
Protein synthesis.
9
Q
Give the function of the cytoplasm
A
Chemical reactions.
10
Q
Give the function of the cell membrane
A
Controls the movement of substances in and out of the cell.
11
Q
Give the function of the cell wall
A
Provides structure and support.
12
Q
Name the chemical that makes the cell wall
A
Cellulose.
13
Q
Give the function of the chloroplasts
A
Photosynthesis.
14
Q
Define a specialised cell
A
A cell adapted to perform a specific function.
15
Q
Name 4 different types of specialised animal cells
A
Nerve cells, muscle cells, sperm cells, red blood cells.
16
Q
Name 3 different types of specialised plant cells
A
Xylem cells, phloem cells, root hair cells, photosynthetic cells.
17
Q
Give the equation to calculate magnification
A
Magnification = Size of Image / Size of real object
18
Q
Calculate how many micrometres are there in a millimetre
A
1000.
19
Q
Define diffusion
A
Movement of particles from high to low concentration.
20
Q
Name 3 factors that affect the rate of diffusion
A
Surface area, concentration gradient, temperature.
21
Q
Define osmosis
A
Diffusion of water from dilute to concentrated solution, across a partially permeable membrane.
22
Q
Define active transport
A
Movement of substances from low to high concentration. Requires energy.
23
Q
Describe how the alveoli in the lungs are adapted for gas exchange
A
Large surface area, good blood supply, thin walls.
24
Q
Describe how the microvilli in the small intestine are adapted to absorb glucose
A
Large surface area, good blood supply, thin walls, lots of mitochondria.
25
Name the three stages of the cell cycle
Replication, Mitosis, division.
26
Describe what happens during replication.
Cell grows and DNA is copied.
27
Describe what happens during mitosis.
Contents of the cell are rearranged - one set of chromosomes are pulled to each end of the cell. Nucleus divides.
28
Describe what happens during division.
Cytoplasm and cell membrane divides. Two identical daughter cells are produced.
29
Define a stem cell.
Unspecialised cell.
30
Define differentiation
Process by which cells become specialised.
31
Give the three types of stem cells.
Embryonic, adult and plant stem cells.
32
State the advantage of using embryonic cells
They can differentiate into almost all types of cells.
33
Give the location of adult stem cells.
Bone marrow.
34
Give the location of plant stem cells.
Meristem tissue in shoots and root tips.
35
Give the advantages of using stem cells.
Cure diseases, increases our knowledge, can be used to increase crop production.
36
Give the disadvantages of using stem cells.
Expensive, research is slow, health effects unknown, adult stem cells can carry viruses, religious/ethical objections.
37
Define cell
Basic unit of living things.
38
Define tissue
Groups of similar cells performing the same function.
39
Define organ
Group of tissues performing the same function.
40
Define organ system
Groups of organs performing the same function.
41
List the three types of tissue
Muscular, glandular and epithelial.
42
Describe the role of bile
Neutralises stomach acid and breaks fats down into droplets.
43
Name the organ where bile is produced
Liver.
44
Name the organs involved in digestion
Mouth, oesophagus, stomach, liver, small intestine, large intestine, anus.
45
Give the function of the small intestine
Reabsorbs glucose from digested food.
46
List the adaptations of the small intestine
Lots of microvilli, good blood supply, thin walls, lots of mitochondria.
47
Name the substance the stomach contains
Hydrochloric acid (pH 3).
48
Name the part of the digestive system responsible for reabsorbing water
Large intestine.
49
Describe the test for starch
Iodine solution. It turns dark blue/black.
50
Describe the test for simple sugars (glucose)
Benedict's solution. It turns brick red when heated.
51
Describe the test for protein
Biuret solution. It turns purple.
52
Describe the test for Lipids (fats)
Ethanol - milky emulsion is formed.
53
What are proteins broken down into?
Amino acids.
54
What are carbohydrates broken into?
Glucose.
55
What are lipids broken down into?
Glycerol and fatty acids.
56
Define enzyme
Biological catalyst (speeds up reactions).
57
Name the three types of digestive enzyme
Amylase (carbohydrase), proteases, lipases.
58
Where is Amylase produced?
Mouth, pancreas, small intestine.
59
Where are protease enzymes produced?
Stomach, pancreas, small intestine.
60
Where are lipase enzymes produced?
Pancreas, small intestine.
61
Describe what happens to an enzyme when the temperature is too hot.
It denatures.
62
Describe how the enzyme changes when it denatures
The active site changes shape irreversibly. The substrate no longer fits. The enzyme won't work.
63
Describe the lock and key mechanism for enzyme action
The active site of each enzyme is specific to one substrate.
64
List the four components of blood
Red blood cells, white blood cells, platelets, plasma.
65
State the function of red blood cells
Carry oxygen.
66
State the 3 functions of white blood cells
Engulf pathogens, make antitoxins, make antibodies.
67
State the function of platelets
Clot the blood.
68
State the function of plasma
Transports substances around the body.
69
Name the three types of blood vessel
Artery, vein, capillary.
70
Describe the structure of an artery
Thick walls, lots of elastic tissue, small lumen.
71
State the function of an artery
Carries oxygenated blood at high pressure, away from the heart.
72
Describe the structure of a vein
Thin walls, small amounts of elastic tissue, large lumen, valves to prevent backflow.
73
State the function of a vein
Carries deoxygenated blood at a low pressure towards the heart.
74
Describe the structure of a capillary
Small lumen, walls one cell thick.
75
State the function of a capillary
Links arteries and veins and helps with diffusion.
76
List the 4 chambers in the heart
Right atrium, right ventricle, left atrium, left ventricle.
77
Describe where the 2 atria are found
At the top of the heart.
78
Describe where the two ventricles are found
At the bottom of the heart.
79
State which side of the heart pumps oxygenated blood
Left.
80
State which side of the heart pumps deoxygenated blood
Right.
81
State the function of the valves in the heart
To stop the blood flowing backwards.
82
Name the blood vessel that takes deoxygenated blood to the lungs
Pulmonary artery.
83
Name the blood vessel through which oxygenated blood is pumped to the body
Aorta.
84
Explain why the human circulatory system is called a double circulation system.
Our circulatory system is split into two loops. One loop takes blood to the lungs, the other takes blood to the body.
85
List 3 methods of treating cardiovascular diseases.
Drugs (statins), mechanical devices (stents, pacemakers, artificial valves/hearts) and transplants.
86
Define coronary heart disease
The narrowing of coronary arteries due to a buildup of fat. This reduces the amount of oxygen reaching the heart and can cause heart attacks.
87
Name 4 plant organs
Roots, stem, leaves, flowers.
88
Name 3 tissues in a leaf
Upper/lower epidermis, palisade mesophyll, spongy mesophyll.
89
State the function of the xylem
Transport water and mineral ions from the roots to the leaves.
90
State the function of the phloem
Transport dissolved sugars from the leaves using translocation.
91
Define stomata
Pores (holes) on the underside of a leaf. Controlled by guard cells.
92
Define transpiration
Evaporation of water via the stomata.
93
List 4 factors that affect the rate of transpiration
Light, temperature, wind, humidity.
94
Describe a communicable disease
Contagious. Caused by pathogens.
95
Describe a non-communicable disease
Non-contagious. Not caused by pathogens.
96
Define a pathogen
Microorganisms that cause disease.
97
List the 4 types of pathogen
Bacteria, Virus, Fungi, Protist.
98
Explain how bacteria cause diseases
Produce toxins.
99
Explain how viruses cause diseases
Take over and destroy cells.
100
Describe how pathogens are spread
Air, water, direct contact.
101
List ways to prevent an infection from spreading
Hygiene, isolation, destroying vectors, vaccines/antibiotics.
102
List three viral diseases
Measles, HIV/AIDS, Tobacco Mosaic Virus (TMV).
103
Describe the characteristics of Measles
Spread by air. Causes fever and a red rash. No treatment, vaccination prevents spread.
104
Describe the characteristics of HIV/AIDS
Spread by sexual contact/exchange of body fluids. Causes flu-like illness and attacks the immune system.
105
Describe the characteristics of TMV
Spread by direct contact and insect vectors. Reduces photosynthesis and growth because leaves lack chlorophyll.
106
List two bacterial diseases
Salmonella, Gonorrhoea.
107
Describe the characteristics of Salmonella
Spread by unhygienic food. Causes stomach cramps, diarrhoea, and vomiting. Poultry vaccinated in the UK.
108
Describe the characteristics of Gonorrhoea
Caused by sexual contact. Causes thick yellow/green discharge and pain on urination. Treated with antibiotics.
109
Describe rose black spot
Fungal disease. Causes black spots on leaves. Reduces photosynthesis and growth. Spread in the air and rain. Treated by fungicides and removing/burning infected leaves.
110
Describe Malaria
Protist disease. Spread by mosquitoes. Infects red blood cells and liver. Causes fever, shaking, and weakness.
111
Explain how we can prevent the spread of malaria
Net to avoid being bitten. Prevent mosquitoes breeding.
112
List the body's primary defences against pathogens
Skin - physical barrier. Nose - hairs and mucus trap pathogens. Trachea - hairs that sweep mucus up throat. Stomach - Hydrochloric acid.
113
List three ways that white blood cells protect us from infection
Phagocytosis - white blood cells engulf pathogens. Antibodies - latch onto and kill pathogens. Antitoxins - chemicals that counteract harmful substances released by pathogens.
