Respiration Flashcards
Introduction
Q1: What is respiration?
Q2: What processes do we need energy for?
Q1: Release of energy from food substances in all living cells Q2: - muscle contraction - active transport - cell division - protein synthesis - growth - passage of nerve impulses - maintenance of constant body temperature
Aerobic Respiration
Q1: What is aerobic respiration?
Q2: What is the equation for aerobic respiration?
Q3: Where exactly does this reaction actually take place?
Q1: the release of a relatively large amount of energy by the breakdown of food substances in the presence of oxygen
Q2: glucose + oxygen → carbon dioxide + water.
C6H12O6 + 6O2 → 6CO2 + 6H2O
Q3: In the mitochondria, which then produce a compound called ATP, which is used as a source of energy for other chemical reactions in the body.
Anaerobic respiration
Q1: What is anaerobic respiration?
Q2: Equation for anaerobic respiration in humans?
Q3: Equation for anaerobic respiration in yeast?
Q4: What happens when we respire anaerobically?
Q1: The release of a relatively smaller amount of energy, in the absence of oxygen.
Q2: C6H12O6 → 2C3H6O3
Glucose → Lactic acid
Q3: glucose → ethanol + carbon dioxide
C6H12 6 → 2C2H5OH + 2CO2
Q4: Lactic acid is produced by the muscles and removed in the bloodstream.
- On reaching the liver, it is oxidised into carbon dioxide and water, using oxygen
- This means our oxygen need remains high, even after we stop exercising.
- The build-up of lactic acid is said to create oxygen debt.
Practicals
Q1: How do we test to prove respiration is happening?
Q2: How to check whether oxygen is being used up?
Q3: How to check whether carbon dioxide is being released?
Q1: Whether energy is being released, whether oxygen is being used, and whether carbon-dioxide is being released.
Q2: Set up a respirometer: Two test tubes in a water bath (for constant temperature), with seeds, cotton wool and soda lime (absorbs carbon-dioxide that is given out), attached to manometers.
Boiled (killed) seedlings in one tube (control)
Germinating seeds in other tube
The manometer level of germinating seeds will rise more than the control.
This does not prove that the gas taken up was oxygen, test using a lighted splint.
Q3: Two large test tubes: one with germinating, one with boiled wheat grains.
Cover the test tube with aluminium foil.
After some time, take gas from above them using a syringe.
Push syringe into limewater and shake it.
The one with germinating seeds should go milky.
Q4: How to check if energy is being released?
Q5: How to check if anaerobic respiration in yeast is happening?
Q6: What is the purpose of having a control in experiments?
Q4: 2 vacuum flask: put sanitised germinating wheat grains in one, dead in the other.
Cover with cotton wool and place a thermometer into both, with its bulb inside the seeds.
Place for 2 days, taking thermometer readings whenever possible.
The living seeds’ temperature should be 15-20 C higher than the dead ones.
Q5: Boil some water (to get rid of oxygen) and make glucose and dry yeast suspension solution.
Put in a test tube, with a layer of liquid paraffin over it. (to exclude atmospheric oxygen)
Put a delivery tube going into a test tube with limewater, and cover with a rubber bung.
Limewater should go milky.
Control: repeat with boiled yeast.
Q6: To make sure the results of the experiment are due to the conditions being studied, and not some other case.
Human Gas exchange
Q1: What are they like, and how do the lungs work?
Q2: How is friction between lungs and thorax reduced?
Q1: They have a spongy texture
They can be expanded and compressed in a way that air is sucked in and blown out
They do not have muscle fibres. They move by the movement of the thorax: by movements of the ribs and diaphragm.
Q2: The outside of the lungs, and inside of thorax are lined with a smooth membrane called pleural membrane
This produces a layer of liquid called pleural fluid which reduces friction between the lungs and the inside of the thorax
Lung capacity
Q1: What is lung capacity when they are fully inflated?
Q2: Air inspired when normally breathing?
Q3: Extra air inspired and expired during exercise?
Q4: What is residual volume?
Q1: 5 litres
Q2: 300 cm cube
Q3: 3 litres
Q4: 1.5 litres of air in the lungs that cannot be breathed out no matter how hard you breathe
Inspired and expired air
Q1: How to find difference in inspired and expired air?
Q1: Oxygen: place a jar in a bowl of water sideways, turn it upside down and put a rubber tube in it (still full of water). breathe into the tube. place a lid on the jar, place a burning candle in it. it will stay alight for lesser time than in a normal jar.
- Carbon-dioxide: Place limewater in two test tubes. rubber bung and short tubes into both. breathe into one and out of one. the one you breathe into turns milky
- Water: breathe onto cobalt chloride paper. turns from blue to pink in the presence of water
Q2: What is the difference between inspired and expired air?
Q3: How to find the effect of physical activity on breathing depth and rate?
Q4: How to find the volume of air in lungs?
Q2: oxygen: inspired: 21%. expired: 16%.
carbon-dioxide: inspired: 0.04%, expired: 4%
water vapor: inspired: variable, expired: saturated (because water from alveoli’s lining evaporates
Q3: Using a spirometer: measures the air breathed in and out of lungs, and the oxygen consumption
Q4: Fill a 5 litre bottle with water. place it upside down in a tub containing some water. put a tube into it and breathe out as hard as you can. this + residual air is volume of air in lungs.
Respiratory System Q1: What is the larynx? Q2: What is the trachea? Q3: What is the bronchus? Q4: What are the bronchioles?
Q1: The area of the throat used for breathing, talking.
Q2: The airway leading from larynx to bronchioles. It joins the lungs to the mouth
Q3: The place where trachea divides into two and enters the lungs. It is a passageway into the lungs.
Q4: Bronchi divide into smaller tubes once they enter the lungs, these deliver air to the alveoli, and are called bronchioles.
Q5: Functions and characteristics of the alveoli?
Q6: Location, function and characteristics of ciliated cells?
Q7: What is ventillation?
Q5: - They have elastic walls, formed from an epithelium.
- They are lined with a film of moisture, so oxygen can dissolve
- beneath the epithelium: a dense network of capillaries, supplies with deoxygenated blood from the heart
- have very large absorbing surface for gaseous exchange.
Q6: location: the epithelium which lines the inside of trachea, bronchi and bronchi has ciliated cells.
- they secrete mucus which forms a thin film over the internal lining: it traps dust particles and bacteria
- movement of the cilia carries it upward, away from the lungs
- once it reaches the top: carried down during swallowing by the esophagus
Q7: The movement of air into and out of lungs which renews our oxygen supply
Exchange of gases
Q1: In what forms does gaseous exchange happen?
Q2: What is the diaghragm?
Q3: Role of ribs in breathing?
Q1: Oxygen: gas dissolves into water, combines with hemoglobin to form oxy-hemoglobin.
- carbon-dioxide: dissolves in water. is released from the plasma when hydrogen-carbonate ions break down to Carbon-dioxide and water
Q2: A sheet of tissue separating the thorax and abdomen which contracts and relaxes to increase and decrease internal volume of lungs
Q3: Ribs cause expansion and contraction of lungs by the movement of intercostal muscles
Q4: Movement of intercostal muscles while breathing?
Q5: Describe diaphragm, ribs, intercostal muscles while inhaling.
Q6: Describe diaphragm, ribs, intercostal muscles while exhaling.
Q4: - external: pull ribs upward and outward
- internal: pull ribs downward and inward
Q5: diaphragm: contracts and flattens
- ribs: move upward and outward
- intercostal: internal: relax. external: contract
Q6: diaphragm: relaxes and becomes dome shaped
- ribs: move downward and inward
- intercostal: internal contract, external relax
