Respiration

Question 1

What is the definition of respiration

Answer 1

The controlled release of energy from organic compounds to produce ATP

Question 2

What is the equation for aerobic respiration

Answer 2

ATP
Glucose + oxygen ————-> carbon dioxide + water

                           C10H16N5O13P3 C6H12O6 + 6O2 —————————> CO2 + H2O

Question 3

What is the definition of ventilation

Answer 3

Breathing, getting air in an out of the lungs

Question 4

Are ventilation and respiration the same

Answer 4

No

Question 5

What is anaerobic respiration, when is it used and where is it used commonly

Answer 5

It is respiration when energy demand exceeds oxygen supply, it does not require oxygen.

It is commonly used in areas deprived of oxygen e.g. mangroves

Question 6

What is the word equation for anaerobic respiration in animals and bacteria

Answer 6

ATP
Glucose ———> lactic acid

Question 7

What is the word equation for anaerobic respiration in plants and fungi

Answer 7

ATP
Glucose ————> ethanol + carbon dioxide

Question 8

What are the disadvantages of anaerobic respiration (3)

Answer 8

1. It is 19x less efficient than aerobic
2. Toxic by-products are produced (lactic acid in animals and bacteria and ethanol in plants and fungi)
3. It can only be sustained for a short period of time (in animals)

Question 9

What compound can be used to measure change in CO2 concentration

Answer 9

Hydrogen carbonate - it changes colour when the CO2 concentration is increased or decreased

Question 10

What is the atmospheric concentration of CO2

Answer 10

0.04%

Question 11

Describe an experiment for measuring the rate of respiration of small animals

Answer 11

Équipement needed: wire gauze, water bath, plastic tubing, clip, bung, capillary tube, soda lime and coloured water

1. Put the soda lime at the bottom of a test tube, then add the wire gauze further up and place the small animals on it.
2. Place the tube in a water bath to keep the temperature constant.
3. Place a bung on the test tube and place a capillary tube from this bung to the coloured water
4. Measure the distance the coloured water goes up the tube and time take, to get the rate of oxygen uptake. This works because oxygen is intaken by the organisms, but the CO2 released is absorbed by the soda lime.
5. Repeat for accuracy and average results

Question 12

Describe an experiment to show the respiration of germinating peas

Answer 12

Equipment list: 3 test tubes, a conical flask, piping, a suction pump, germinating peas, lime water and potasssium hydroxide

1. Fill the conical flask with peas, 2 test tubes with lime water and 1 test tube with potassium hydroxide
2. Put two pipes in each one, with the following setup: potassium hydroxide connects to air and limewater, which connects to germinating peas, which connects to limewater, which connects to the suction pump.
3. The potassium hydroxide will absorb CO2 coming in from the air, so the first limewater should stay clear. However, as the germinating peas respire and air is sucked out of the germinating peas flask, into the final test tube and into the suction pump, the CO2 produced by the germinating peas should make the limewater in the final test tube cloudy.

Question 13

What are the muscles between the ribs called

Answer 13

Intercostal muscles

Question 14

What is the diaphragm

Answer 14

A powerful set of muscle separating the thorax from the abdomen

Question 15

What is the trachea

Answer 15

The windpipe. Connects the larynx to the bronchioles

Question 16

What is the larynx

Answer 16

The voice box (creates your voice)

Question 17

What is a bronchiole

Answer 17

Small, thin walled air passages in the lungs that branch off from the bronchi and lead to alveoli, where gas exchange occurs. They transport air to the alveoli.

Question 18

What is the alveoli

Answer 18

Tiny air sacs at the end of the bronchioles where gas exchange occurs. Exchanges oxygen and CO2 between the lungs and bloodstream via their thin walls

Question 19

What is expiration

Answer 19

Breathing out

Question 20

What is inspiration

Answer 20

Breathing in

Question 21

What happens when we breathe in (5)

Answer 21

1. The external intercostal muscles contract and raise the ribs upwards and outwards
2. The diaphragm muscle contracts and flattens
3. The volume of the thorax increases
4. The air pressure in the thoracic cavity falls below that of atmospheric air
5. Air rushes into the lungs along a pressure gradient

Question 22

What happens when we breathe out (5)

Answer 22

1. The external intercostal muscles relax and the ribs move downwards and inwards
2. The diaphragm muscle relaxes and becomes dome-shaped
3. The volume of the thorax decreases
4. The air pressure in the thoracic cavity rises above that of the atmospheric pressure
5. Air rushes out of the lungs along a pressure gradient

Question 23

How to draw a lung

Answer 23

See Human Gas Exchange note

Question 24

Why are alveoli suited to a fast rate of diffusion (3)

Answer 24

1. A huge number of alveoli create a large surface area
2. The cells are very thin, only one cell thick
3. A strong blood supply maintains a high concentration difference

Question 25

How to draw an alveoli

Answer 25

See Human Gas Exchange note A circle with a tube going into it, then a ring of red blood cells in a tube around it

Question 26

What is the gas exchange in the alveoli and what parts of the blood are affected

Answer 26

Oxygen enters the haemoglobin from the alveoli Carbon dioxide leaves the blood plasma and enters the alveoli

Question 27

What is systolic blood pressure

Answer 27

The maximum blood pressure experienced

Question 28

What is a sphygomomanometer (probably not required for gcse)

Answer 28

A device that measures heart rate

Question 29

What structure should you use to design a biological experiment

Answer 29

CORMSS C- what **changes** O - what **organism** will you use and what needs to be kept the same about it R - how many **repeats** will you do to ensure reliability and what must be done if you get unreliable results M - what is one thing you will **measure** (dependent variable) S - **what** three factors will you keep the **same** S - **how** will you keep these factors the **same**

Question 30

What technique should be used for drawing graphs

Answer 30

SLAPUK S- scale L - line of best fit or other if requested A - axes. Independent variable on x-axis. Label axes P - points plotted correctly U - units K - key (if applicable)

Question 31

What is important to answering biology questions

Answer 31

Use key words related to the question e.g. if the question asks how enzymes work, words like catalyst, active site, lower activation energy etc are going to be on the mark scheme

Question 32

What is the definition of osmosis

Answer 32

The movement of water molecules from an area of low solute concentration to an area of high solute concentration through a selectively permeable membrane

Question 33

What is the definition of active transport

Answer 33

The movement of particles through a selectively permeable cell membrane for a a region of lower concentration to a region of higher concentration using ENERGY from respiration

Question 34

What is the definition of diffusion

Answer 34

The net movement of particles from an area of high concentration to an area of low concentration

Question 35

Which is not passive (requires energy): active transport, osmosis or diffusion

Answer 35

Active transport

Question 36

Which does not involve the transport of solutes (only water transported): active transport, osmosis or diffusion

Answer 36

Osmosis

Question 37

Which of these occur in nature: active transport, osmosis or diffusion

Answer 37

All

Question 38

Which of these need a semi-permeable membrane: v active transport, osmosis or diffusion

Answer 38

All

Question 39

Which is high to low concentration (follows concentration gradient) and which is low to high concentration (against the gradient): active transport osmosis and diffusion

Answer 39

Active transport is against, diffusion is with

Question 40

What is the C:H:O ratio almost always in carbs

Answer 40

1:2:1 e.g glucose is C6H12O6

Question 41

Are carbohydrates soluble or insoluble

Answer 41

Some are soluble, some are insoluble

Question 42

Give an example of a soluble and insoluble carbohydrate

Answer 42

Soluble: glucose Insoluble: starch

Question 43

What are starch and glycogen examples of

Answer 43

Long chains of glucose molecules

Question 44

Which is quicker to turn into glucose: glycogen or starch

Answer 44

Glycogen

Question 45

How to test for starch

Answer 45

Add iodine - brown-yellow will become blue-black

Question 46

How to test for glucose

Answer 46

Boil with Benedict’s solution: blue to brick red if glucose is present.

Question 47

When testing for glucose, what do the following colours mean: blue, green, yellow, orange, brick red

Answer 47

Blue - no glucose Green - a low concentration of glucose Yellow - a moderate concentration of glucose Orange - between a moderate and high glucose concentration Brick red - high concentration of glucose

Question 48

What is the structure of lipids

Answer 48

Glycerol + 3 fatty acids. Glycerol is drawn pill shaped and the fatty acids are drawn as parallel lines coming off of the glycerol

Question 49

What breaks the bond between glycerol and the 3 fatty acids

Answer 49

Lipase

Question 50

What are lipids for

Answer 50

Insulation and support

Question 51

How to test for lipids

Answer 51

Emulsion test: dissolve the lipid, add water and ethanol, then shake. If cloudy, lipids are present, if clear, no lipid

Question 52

How to test for lipids

Answer 52

Emulsion test: dissolve the lipid, add distilled water and ethanol, then shake. If cloudy/white, lipids are present, if clear/colourless then they are not

Question 53

How do we get proteins and in what form

Answer 53

From the food we eat - amino acid form

Question 54

What are proteins used for

Answer 54

Growth and repair

Question 55

What are proteins determined by

Answer 55

DNA

Question 56

How to test for protein

Answer 56

Add the burette reagent - blue to lilac if protein is present, stays blue if not

Question 57

List the structures that air passes through on its way from the nose to the alveoli

Answer 57

Nasal cavity -> pharynx -> larynx -> trachea -> Alveoli

Question 58

Why do animals need lungs rather than exchanging gas through the skin (2)

Answer 58

1. The surface area of lungs is larger than skin, allowing for more gas exchange to happen 2. Ventilation can be done as much or as little as needed with lungs but not with skin

Question 59

What is the difference in composition between inhaled air and exhaled air

Answer 59

Inhaled has a lot more oxygen, but exhaled has a lot more CO2

Question 60

Why does breathing get faster and deeper during exercise

Answer 60

The body needs more oxygen because it needs more energy, which is produced through respiration, which requires oxygen

Question 61

What chemicals are in cigarette smoke and what are they (3)

Answer 61

1. Nicotine - addictive drug 2. Tar - a sticky brown substance that is deposited in the lungs. It is a carcinogen 3. Carbon monoxide - reduces the oxygen carrying capability of blood

Question 62

Is smoking bad for you and should it be stopped

Answer 62

Yes it is bad for you and yes it should be stopped

Question 63

What are some regulations (UK) to limit smoking and passive smoking

Answer 63

1. The purchase age of cigarettes is 18, with the government planning to put this up 1 year every year, so those born in and after 2009 can never legally buy cigarettes 2. Smoking in public places is now banned 2. The packets have bad messages and pictures showing the damage they can do to try and discourage people from smoking 3. They are taxed a lot to increase the price - 76% of cigarette price is tax

Question 64

What is passive smoking

Answer 64

When you breathe in cigarette smoke but you are not the smoker