Topic 2: Organisation

Question 1

A tissue is…?

Answer 1

A group of similar cells that work together to carry out a particular function

Question 2

An organ is…?

Answer 2

A group of different tissues that work together to perform a particular function

Question 3

An organ system is…?

Answer 3

A group of organs that work together to perform a particular function

Question 4

A catalyst is…?

Answer 4

A substance which increases the speed of a reaction, without being changed or used up in the reaction. (it LOWERS the activation energy) enzymes are biological catalysts

Question 5

Factors affecting enzymes?

Answer 5

Temperature and pH
If the temperature gets too hot, the bonds holding the enzyme together break. This changes the shape of the enzyme’s active site so the substrate won’t fit anymore.

If the pH is too high or low, the pH interferes with the bonds too

The enzyme will DENATURE

Question 6

Enzyme RP

Answer 6

Put a drop of iodine into every well on a spotting tile
Use a water bath to control the temperature of the amylase, buffer solution and starch
Use continuous sampling to record how long it takes for the amylase to break down all of the starch. USe a pipette to take a fresh sample from the boiling tube every 30 secs and put a drop into the well. When the iodine solution is browny orange, starch is no longer present

Question 7

Carbohydrases convert…?

Answer 7

Carbohydrates into simple sugars

in the salivary glands
pancreas
small intestine

Question 8

Proteases convert…?

Answer 8

Proteins into amino acids
the stomach
pancreas
small intestine

Question 9

Lipases convert…?

Answer 9

Lipids into glycerol and fatty acids
pancreas
small intestine

Question 10

amylase breaks down…?

Answer 10

Starch and is made in the salivary glands, pancreas and small intestine

Question 11

The function of bile?

Answer 11

Bile neutralises the stomach acids and emulsifies fats. It’s produced in the liver and stored in the gall bladder before being released into the small intestine.

Question 12

The salivary glands…?

Answer 12

Produce amylase enzymes in the saliva

Question 13

The liver…?

Answer 13

Produces bile which neutralises the stomach acids and emulsifies fats

Question 14

The large intestine…?

Answer 14

Absorbs excess water from the food

Question 15

The stomach…?

Answer 15

Pummels food with its muscular walls
Produces the protease enzyme: pepsin
Produces hydrochloric acid to kill bacteria and to give the right pH for pepsin to work

Question 16

The pancreas…?

Answer 16

Produces protease, amylase and lipase enzymes and releases them into the small intestine

Question 17

The small intestine…?

Answer 17

Produces protease, amylase and lipase enzymes to complete digestion
And is also where digested food is absorbed into the blood.

Question 18

The rectum…?

Answer 18

Is where faeces is stored before it travels out of the body through the anus.

Question 19

Food testing RP?

Answer 19

Break up a food specimen with a pestle and mortar
Add distilled water and stir to dissolve some of the food
Filter to get rid of big lumps
Then add certain chemicals to determine what chemicals are present…

Question 20

Testing for Sugars?

Answer 20

Use Benedict’s solution to test for simple sugars. Heat the solution. In the presence of sugars, it will turn from blue to either green, yellow or brick-red depending on how much sugar is in the food.

Question 21

Testing for Starch?

Answer 21

Use iodine solution. It should change from browny-orange to black or dark blue.

Question 22

Testing for Proteins?

Answer 22

Use biuret solution. It should change from blue to pink or purple

Question 23

Testing for Lipids?

Answer 23

Use Sudan III stain solution. It should stain the lipids and the mixture will separate into two layers. The top layer will be bright red. If no lipids are present, no red layer will form.

Question 24

How does the heart work?

Answer 24

The blood flows into the two atria from the vena cava (from the body) and the pulmonary vein (from the lungs)

The atria contract, pushing the blood into the ventricles

the ventricles contract, forcing the blood into the pulmonary artery ( to the lungs) and the aorta (to the body), and out of the heart

The blood then flows to the organs through the arteries and returns through the veins.

Question 25

Arteries and Veins

Answer 25

Arteries go Away from the heart | veINs go INto the heart

Question 26

The pulmonary vein

Answer 26

A vein on the left side, going into the heart from the lungs

Question 27

The pulmonary artery

Answer 27

An artery on the right side, taking blood away from the heart to the lungs

Question 28

Aorta

Answer 28

An artery on the left side going away from the heart to the body

Question 29

Vena cava

Answer 29

A vein on the right side, going into the heart from the body

Question 30

Ventricles are...?

Answer 30

The two bottom chambers of the heart

Question 31

Atria (atrium sng.) are...?

Answer 31

The two top chambers of the heart

Question 32

Where is the natural pacemaker located inside the heart?

Answer 32

The pacemaker is located in the right atrium wall and produces small electrical impulses which cause the muscles to contract.

Question 33

The coronary arteries are...?

Answer 33

Arteries which branch off of the aorta and surround the heart, making sure it gets all of the oxygenated blood it needs.

Question 34

Three different types of blood vessels and their function?

Answer 34

Arteries - these carry the blood away from the heart Capillaries - Involved in the exchange of materials at the tissues. Veins - carry the blood to the heart.

Question 35

Arteries...?

Answer 35

Carry blood under pressure The walls are thick compared to the size of the lumen (hole down the middle) Thick muscle layers to strengthen and elastic fibres allowing them to stretch

Question 36

Capillaries...?

Answer 36

Very small They have permeable walls, so substances can diffuse in and out They supply food and oxygen and take away waste Their walls are usually only 1 cell thick, increasing the rate of diffusion

Question 37

Veins...?

Answer 37

have a bigger lumen than arteries to help blood flow despite the lower pressure They also have valves to keep blood flowing in the right direction

Question 38

Red blood cells...?

Answer 38

Carry oxygen from the lungs around the body Are biconcave, giving a large surface area for absorbing more oxygen They don't have a nucleus Contain a red pigment called haemoglobin, which binds to the oxygen to become oxyhaemoglobin.

Question 39

Platelets...?

Answer 39

Help the blood to clot

Question 40

Plasma is the...?

Answer 40

The straw-coloured liquid that carries everything in the blood Red and white blood cells and platelets Glucose and amino acids (nutrients) Carbon dioxide from the organs to the lungs Urea from the liver to the kidneys Hormones Proteins Antibodies and antitoxins produced by the white blood cells

Question 41

What is coronary heart disease?

Answer 41

Is when the coronary arteries that supply blood to the muscle of the heart get blocked by layers of fatty material building up. Causing the arteries to become narrow, so blood flow is restricted and there's a lack of oxygen to the heart muscle. - can result in a heart attack

Question 42

How do stents help coronary heart disease?

Answer 42

``` They are tubes that are inserted inside the arteries. They keep them open, making sure blood can pass through to the heart. Effective for a long time Short recovery Infection from surgery Blood clot developing - thrombosis ```

Question 43

What are statins?

Answer 43

Drugs that reduce the amount of 'bad' cholesterol present in the bloodstream

Question 44

Adv and Disadv of statins?

Answer 44

Reduces the risk of strokes, CHD and heart attacks can increase the amount of 'beneficial' cholesterol May also help prevent other diseases Long-term drugs that must be taken regularly Negative side effects - headaches Serious side effects - kidney failure, liver damage and memory loss

Question 45

Other ways to prevent or treat CHD?

Answer 45

An artificial heart/ valves could wither be mechanical or biological Biological - less likely to be rejected Bleeding, infection and clotting from surgery

Question 46

Communicable and non communicable diseases?

Answer 46

Communicable - can be spread from person to person or between animals and people Bacteria, viruses, parasites and fungi Measles and malaria Non - Cannot spread between people or animals. Last for a long time Get worse slowly Asthma cancer and coronary heart disease

Question 47

Risk factors for getting non-communicable diseases

Answer 47

``` Lifestyle exercise environment - pollution substances in your body - asbestos in developed countries, non-c diseases are more common as people have a higher income and can buy high-fat food ``` Smoking Too much alcohol Smoking when pregnant can harm the baby Cancer caused by exposure to certain substances or radiation - carcinogens. Ionising radiation (x-rays) = carcinogen

Question 48

Cancer is caused by...?

Answer 48

Uncontrolled cell growth and division

Question 49

Benign and malignant tumours

Answer 49

Benign - Tumour grows until there's no more room. Doesn't invade other tissues in the body and isn't dangerous or cancerous Malignant - tumour grows and spreads to neighbouring healthy tissues. Cells can break off and spread to other parts of the body through the blood. Dangerous, and can be fatal - CANCER

Question 50

Risk factors for cancer?

Answer 50

Smoking Obesity UV Exposure Viral infection - HPV virus can lead to cervical cancer for women

Question 51

Epidermal tissue...?

Answer 51

covers the whole plant. Covered with a waxy cuticle, which helps to reduce water loss by evaporation Upper epidermis is transparent so that light can pass through to the palisade layer

Question 52

Palisade mesophyll tissue...?

Answer 52

Is the part of the leaf where most of the photosynthesis happens. A lot of chloroplasts, near to the top to get the most light.

Question 53

Spongey mesophyll tissue...?

Answer 53

Also in the leaf, and contains big air sacs to allow gasses to diffuse in and out.

Question 54

Xylem and Phloem...?

Answer 54

transport water, mineral ions (XYLEM) and food (PHLOEM) around the plant. They form a network of vascular bundles and help support the structure.

Question 55

Meristem tissue...?

Answer 55

Is found at the growing tips of shoots and roots and is able to differentiate into different cell types. Allowing the cell to grow.

Question 56

Phloem?

Answer 56

Made of columns of elongated LIVING cells with small pores in the end walls to allow cell sap to flow through. They transport food substances (mainly dissolved sugars) made in the leaves to the rest of the plant for immediate use or for storage. BOTH DIRECTIONS called TRANSLOCATION

Question 57

Xylem?

Answer 57

Made of DEAD cells joined end to end with NO end walls between them and a hole down the middle Carry water and mineral ions from the roots to the stem and leaves The movement of water from the roots, through the xylem and out of the leaves is called TRANSPIRATION.

Question 58

Transpiration is the...?

Answer 58

Loss of water from the plant

Question 59

What affects the rate of transpiration?

Answer 59

Light intensity - the brighter the light, the greater the TR - stomata begin to close as it gets darker and photosynthesis cant happen in the dark Temperature - The warmer, the greater rate - Water particles have more energy to evaporate and diffuse out of the stomata Airflow - the better the air flow, the greater the rate - If airflow is poor, the water vapour just surrounds the leaf and there's a higher concentration of water particles outside the leaf as well as in it so diffusion is slowed. Humidity - The drier the air around the leaf, the faster transpiration happens - If air is humid, not much of a concentration gradient

Question 60

How are guard cells adapted?

Answer 60

They open and close stomata and are adapted for gas exchange and controlling water loss in a leaf. Kidney Shape Lots of water in the plant to fill it and it will go turgid, makes the stomata open and gasses exchange for photosynthesis The plant is short of water - lose water and become flaccid making them close - helps stop water vapour escaping Thin outer walls and thin inner walls Sensitive to light and will close at night to save water More on undersides of leaves - cooler and shaded so less water is lost than if they were on the upper side.

Question 61

How do you measure the rate of transpiration?

Answer 61

By measuring the uptake of water by a plant Use a potometer and record the starting position of the air bubble, record the distance moved by the bubble per time unit. Keep conditions (temp / humidity) constant throughout.