Topic B2 - Organisation Flashcards
1
Q
Describe cell organisation?
A
Unspecialised cells (stem cells) ==> Specialised cells
Many similar specialised cells ==> Tissue
Many different types of tissues ==> Organ
Many different organs ==> Individual
2
Q
What are three examples of tissues?
A
Muscular tissues
Glandular tissue
Epithelial tissue
3
Q
What is the function of muscular tissue?
A
Contracts/moves to what its attached to.
4
Q
What is the function of glandular tissue?
A
Makes and secrets hormones and enzymes.
5
Q
What is the function of epithelial tissue?
A
Layers certain organs eg. stomach
6
Q
What is an organ?
A
An organ is a collection of specialised tissues to perform a certain function.
7
Q
What is an organ system
A
A combination of organs working together to perform a certain function.
8
Q
The stomach is made up of a group of tissues, what are they?
A
Muscular==>Contacts in order to churn the food
Glandular==>Makes the digestive juices, digest the food
Epithelial==>Covers the inside and outside layer with mucus to prevent damage
9
Q
What are some of the organs in our body?
A
Brain Eyes Ears Nose Mouth Lungs Heart Oesophagus Stomach Small Intestine Large intestine
10
Q
What is the purpose of your mouth?
A
Mechanical Digestion - churning of food via teeth
Chemical Digestion via amylase produced in the salivary gland found in saliva.
11
Q
What is the purpose of the oesophagus?
A
Transporting of food via peristalsis movement and the muscle contractions move the food along
12
Q
What is the function of the stomach?
A
> Mechanical digestion via muscle contractions to churn the food.
Chemical digestion via hydrochloric acid and enzymes such as pepsin which breaks down proteins into amino acids.
It also kills bacteria found in food.
13
Q
What is the function of the liver?
A
The liver produces bile. Bile emulsifies fats and this helps to break them down whilst neutralising stomach acid.
14
Q
What is the function of the gall bladder?
A
To store bile when released into the small intestines.
15
Q
What is the function of the pancreas?
A
The pancreas produces enzymes such as protease, amylase and lipase.
16
Q
What is the function of the small intestine?
A
The small intestine is the main site of digestion and absorption in order to complete digestion. Enzymes such as protease. amylase and lipase.
17
Q
What is the function of the large intestine?
A
Absorption of water from food to produce faeces.
18
Q
What is the function of the rectum?
A
Faeces is stored here via the anus.
19
Q
What is an enzyme?
A
A biological catalyst that speeds up reactions without getting used up.
20
Q
What is the lock and key model.
A
The substrate must be complimentary to the shape of the active site for enzymatic activity to occur.
21
Q
Word equation for lock and key model.
A
e+s==> es ==> e+p
22
Q
What are the two factors that enzyme activity?
A
Temperature (Optimum)
pH levels
N.B different enzymes have different optimum temps and ph level.
23
Q
What happens when the conditions are not met?
A
The enzyme becomes denatured.
24
Q
What are the types of food groups?
A
Proteins
Carbohydrates
Fats
Fibres, vitamins and minerals.
25
What enzymes break down the following: Proteins, Carbohydrates and fats?
Protease, amylase and lipase.
26
What does protease break proteins into?
Amino acids
27
Where are protease produced at?
Stomach - pepsin
Pancreas
Small Intestine
28
What do lipase break lipids into?
Glycerol and fatty acids.
29
Where is lipase produced?
Pancreas
| Small intestine
30
What is starch broken down to?
Maltose (sugars)
31
Where is amylase produced?
Small intestines
Pancreas
Salivary glands
32
What is the function of bile?
Bile emulfises fats and neutralises
33
What test is used to test for sugars?
Benedict's test
34
What happens to the benedict's solution when sugar is present?
From blue green to yellow or brick red.
35
What test is used to test for starch?
Iodine solution
36
What happens to the iodine solution when starch is present?
From brown-orange to blue-black.
37
What test is used to test for proteins?
Biuret test
38
What happens to the Biuret solution when proteins are present?
From blue to pink or purple,
39
What test is used to test for the presence of lipids?
The Sudan III test
40
What happens to the Sudan III solution when lipids are present?
The Sudan III solution will form a red layer if lipids are present.
41
How do you calculate the rate of an enzymatic reaction?
Rate = 1000/time
42
Describe the organisation of the lungs?
Trachea ==> Bronchi ==> Bronchioles ==> Alveoli
43
What is the thorax?
Space between the neck and the diaphragm
44
What muscles can be found between our ribs?
Intercostal muscles
45
What membranes covers the lungs?
Pleural membrane
| > Double layered membrane, which contains pleural fluid.
46
Where does gaseous exchange take place within the lungs?
Inside the alveoli
47
What happens during gaseous exchange within the alveoli?
> CO2 diffuses out of the deoxygenated blood and into the alveolus where it becomes expired.
> O2 diffuses from the alveolus into the deoxygenated blood, oxygenating it as a result. Oxygenated blood then returns to the heart via pulmonary veins.
48
What is the difference between arteries and veins?
ARTERIES carry blood AWAY from the heart.
| Veins carry blood towards the heart.
49
What is a double circulatory system?
The system in which the heart acts like a double circuit deoxygenated blood leaves the heart via the right side, goes to the lungs and returns with oxygenated blood via the pulmonary vein, simultaneously.
50
What is a pacemaker?
Regulates the rate of the heart beat.
51
Where are pacemaker cells located?
They are found in the right atrium. (Sinoatrial node)
52
What does a pacemaker do?
Generates a small electrical impulse generating a beat.
53
Why are artificial pacemakers used?
They are used if natural pacemakers cells do not work properly they treat conditions. To control heartbeat.
54
What are the three types of blood vessels?
Arteries
Veins
Capillaries
55
What is the function of the arteries?
They carry blood away from the heart
56
What is the function of the vein
They carry blood towards the heart
57
What is the function of the capillaries?
The exchange of material at the tissues.
58
What is the structure of an artery?
The heart pumps out blood at high pressure the walls are strong and thick, a regular sized lumen in order to keep the pressure.
59
What is the structure of a vein?
The blood travel back to the heart at low pressure.
They have a bigger lumen to aid blood flow even though pressure is low.
They have valves to keep the blood flowing in the right direction and prevent backflow.
60
What is the structure of a capillary?
Capillaries are very small, they are one cell thick in order aid diffusion.
They carry the blood close to other cells in order to exchange substances such as food and oxygen.
They have permeable walls in order for diffusion to take place easily and the one cell thick structure also allows this.
61
What is rate of blood flow?
rate of bf=volume of blood/minutes
62
What is the function of the red blood cell?
Red blood cells carry oxygen around the body.
63
What is the structure of a red blood cell?
They have a biconcave structure providing them with a large surface area and them not carrying a nucleus allows more oxygen to be carried.
64
What pigment carries 02 found within red blood cells carry oxygen?
Haemoglobin
65
What is haemoglobin known as when bound to oxygen
Oxyhaemoglobin
66
What happens to oxyhaemoglobin in tissues?
In tissues oxyhaemoglobin splits to into haemoglobin and oxygen, releasing oxygen into the cells.
67
What is the function of a white blood cell?
White blood cells fend against infection.
68
How do white blood cells defend against infection?
They engulf and absorb waste, microorganisms, and foreign bodies in the bloodstream and tissues. Some produce antibodies to fight microorganisms as well as antitoxins to neutralise toxins produced via foreign bodies.
69
What are platelets?
Small cluster of cells; they have no nucleus.
70
What is the function of platelets
They aid the blood to clot, preventing microorganisms from entering and prevent blood loss.
71
What is plasma?
Plasma is the liquid that carries substances in the blood.
72
What are examples of substances carried by blood plasma?
```
>Red and white blood cells
>Nutrients - glucose and amino acids
>Carbon dioxide
>Urea
>Hormones
>Proteins
```
73
What is coronary heart disease?
Coronary heart disease is when the coronary arteries get clogged up with fatty deposits which causes the arteries to narrow, restricting blood flow and henceforth a lack of oxygen is provided for the heart, this could possibly lead to a heart attack.
74
What are stents?
Stents are tubes inserted into the arteries, opening up the lumen to increase blood flow.
75
What are the benefits of using a stent?
A stent lowers the risk of a heart attack from occurring and are effective in the long run. The recovery time is fairly quick.
76
What is a drawback of using a stent?
There is a risk of complications from occurring during the experiment as well as risk of infection from the surgery.
There is a risk that patients may develop a blood clot near the stent.
77
What is cholesterol?
A lipid that is required for the body to function. Too much cholesterol can cause health conditions.
78
What happens when you have too much cholesterol?
A high amount of cholesterol can cause fatty deposits to develop in the arteries.
79
What are statins?
Statins are drugs that reduce the high levels of cholesterol in the bloodstream which reduces rate of fatty deposits forming.
80
What are the advantages of using statins?
>By reduce cholesterol levels, they reduce the risk of coronary heart disease, heart attack and strokes.
>As well as reducing harmful cholesterol, they also increase beneficial cholesterol which can remove the bad cholesterol.
81
What are the disadvantages of using statins?
>They are a long term drug that must be taken regularly, there's the risk of forgetting to take them
>Statins can have negative side effects such as headaches. Sometimes it may have serious side effects such as kidney and liver failure, memory loss.
82
What is emulsification?
It breaks down large drops of fat into smaller ones. The larger surface area allows lipase to chemically break down the lipid into glycerol and fatty acids faster.
83
What happens when we ventilate?
>The ribcage moves up and out and the diaphragm moves down causing the volume of the
chest to increase.
> Increased volume results in lower pressure.
>Air is drawn into the chest as air moves from areas high pressure (the environment) to low
pressure (the lungs).
>The opposite happens when exhaling.
84
What happens at heart failure?
>A heart transplant may be required using donor organs from donors; if unavailable an artificial heart may be required.
85
What is the use of an artificial heart?
They are mechanical devices that pump blood, they are a temporary fix until a donor heart is located in order to keep the person alive; some cases its a permanent fix.
86
What is the advantage of using an artificial heart?
They are less likely to be rejected by the immune system due to the materials metal and plastics which the body does recognise as foreign
87
What are disadvantages to the use of an artificial heart?
To fit in the heart can lead to bleeding and infection.
They don't work as well as a normal heart; they wear out and the motor could fail.
Blood doesn't flow smoothly and blood clots may occur leading to strokes
Patient may need to take drugs to thin the blood to prevent this.
88
What can happen to valves?
Valves can be damaged or weakened via heart attacks, infection and age.
89
What can damage do to the valves and treatment?
>This may cause tissue to stiffen so it doesn't open properly.
>A valve may become leaky, blood flowing in both directions which reduces circulation
>Severe damage can be treated by replacing the valves;it is less traumatic than a heart transplant.
90
What do you do when a valve doesn't work?
Replace it either with a biological valve made from humans/mammals or mechanical valves.
91
What is the use of artificial blood?
When someone loses a large amount of blood it can be used to keep one alive. It gives people enough time to produce new blood cells; if not the patient will require a blood transfusion.
92
What is artificial blood?
A substitute to replace the volume of lost blood.
93
What are the two types of disease?
Communicable and non communicable>
94
What is a communicable disease?
Communicable diseases are infectious as they are caused by pathogens (bacteria, viruses, fungi) and are passed on from one person to another.
95
What is a non communicable disease?
Non communicable diseases are not passed on from person to person. eg. cancer, heart disease.
96
What are the effects of different types of diseases?*
>A weak immune system makes one prone to illnesses from communicable diseases as the body is less able to defend itself
>Infections by viruses in certain parts of the body can trigger the growth of cancers. For example, liver cancer can result from infection by hepatitis virus.
> Immune system reactions, can trigger allergic reactions. The reaction may be rashes, or an increase in the severity of asthma attacks
97
What other factors can affect your health?
>Diet - eating too little or too much food prevents you from having a good, balanced diet. This can have an effect on mental and physical health.
> Stress: Physical and mental stress strains our body. This can lead to problems such as heart disease, cancers and mental illnesses.
98
What risk factors can increase the chance of getting a disease?*
>Lifestyle, or substances in the person’s body (asbestos fibres, material used in buildings, found in airways) or
environment (UV rays from the sun).
99
What risk factors can directly cause a disease?
>Smoking causes cardiovascular disease and lung cancer by damaging the walls of arteries.
>Obesity causes type 2 diabetes by making the body less resistant to insulin.
>Alcohol causes damage nerve cells in the brain ad liver disease.
100
What are the two types of tumours?
Malignant
| Benign
101
What the difference between malignant and benign tumours?
Benign==> regulated cell growth, doesn't metastasis(reach another organ via bloodstream)
Malignant ==>uncontrolled, rapid cell growth infiltrates the basement membrane and reaches other organs.
102
What are the different stages of the cell cycle?
Cell prepares itself for division
| Interphase
103
Compare cell cycle and the one of the malignant cell cycle.
Normal cell cycle - checkpoints are established, regulated cell division
Malignant - checkpoints are faulty, unregulated cell division
104
What are risk factors of getting cancer?
```
Obesity
Smoking - lung cancer
UV exposure - skin cancer
Viral infection - HIV/Hepatitis B
Genetic - faulty genes (BRCA1 - breast/ovarian cancer)
```
105
What is the structure of the leaf?
```
Waxy cuticle
Epidermal tissue
Palisade Mesophyll tissue
Spongy Mesophyll tissue
Xylem and phloem
Guard cells and Stomata
```
106
What is the function of the waxy cuticle?
The waxy cuticle prevents excessive water loss (transpiration)
107
What is the function of the epidermal tissue?
The layers cover the plant
108
What is the function of the palisade mesophyll?
Palisade mesophyll is where the chloroplasts are found, photosynthesis takes place here.
109
Why is the palisade mesophyll near the top of the leaf?
To ensure the maximum light absorption takes place
110
What is the function of the spongy mesophyll?
Contains air spaces to allow O2 to diffuse out of the leaf and carbon dioxide inside the plant.
111
What is the function of the guard cells?
They control the size of the stomata
112
What is the function of the stomata?
Enables the movement of gases and water entering or le
113
What is the function of the xylem?
Transports water
114
What is the function of the phloem?
Transports food - sugars, amino acids and minerals
115
Where are meristem cells located?
Tips of the shoots and the roots
116
What is the function of the meristem cells?
Generation of tissues - they are stem cells.
117
What property of the upper epidermis is essential in photosynthesis?
Transparent layer, allowing light to enter
118
How is the phloem tube structured?
Made up of columns of elongated cells, that have no nucleus, with small pores to allow sap through.
Sieve-like structure to compartmentalise the phloem and ensure selective transport between adjacent compartments.
119
How is the xylem tube structured?
Made up of dead cells joined together with a hole down the middle.
120
What is the name for the process in transporting food?
Translocation
121
Compare the flow of nutrients between the phloem and the xylem?
Phloem - bidirectional
| Xylem - unidirectional
122
What is transpiration?
The loss of water.
123
What factors determine the rate of transpiration?
Light intensity - the higher the light intensity, higher the rate of photosynthesis so more O2 produces so stomata is open meaning water is lost at the same time.
Humidity - More water particles on outside, concentration gradient is reduced so water is conserved.
Temperature - increases the rate in which water moves up the xylem and as a result of the increased rate, water is lost.
Wind direction - Water on outside of leaf is less than inside, osmosis is high here, the wind blows away the water increasing the concentration gradient which increases the rate of osmosis and transpiration.
124
What apparatus is used to measure rate of transpiration?
Photometer
125
How does photometer work?
Air bubble in a tube is an indicator of how much water is taken up by the plant. water lost=water gained
126
What causes the stomata to open?
High water and oxygen concentration, water moves into the guard cell making them turgid and causing stomata to open.
127
What causes the stomata to close?
Low water and oxygen concentration and the guard cell is flaccid and this closes the stomata.
128
What impact does light intensity have on a guard cell?
Daytime - open as there is light, which influences the rate of photosynthesis, therefore oxygen production is increased and therefore stomata is open.
Nightime - closed as there is no light which wouldn't affect the rate of photosynthesis therefore no O2 produced and therefore stomata opening is unnecessary.
