Respiration – a chemical reaction
1.
What is the main purpose in respiration?
The process by which organisms release energy from food is called respiration.
There are two types of respiration:
-Aerobic respiration
-Anaerobic respiration
Aerobic Respiration
2.
What are the reactants of aerobic respiration?
Glucose + Oxygen = Carbon dioxide + water + energy
3.
Write a balanced chemical equation for the process of aerobic respiration.
C6H12O6 + 6O2 = 6CO2 + 6H2O + energy
4.
Why are enzymes called biological catalysts?
Enzymes are complex protein molecules which act as a biological catalysts. A
catalyst is something which speeds up a chemical reaction without itself being
used up in the reaction.
5.
Use diagrams to help you explain why enzymes are so specific.
6.
The energy released during respiration is taken up by a special energy-transfer
molecule.
a) They are called ATP and ATD
b) It serves as the immediate source of energy for all cell activities.
7.
List three possible uses of energy in cells
Everything you do requires energy for example:
-Walking up the stairs
-Drinking water
-Running in a race
-Texting a friend
7.1, Questions- Kelsey Fuller
Anaerobic Respiration
8.
What does the term ‘anaerobic respiration’ mean?
Anaerobic respiration uses glucose as its fuel and still provided energy, but it is a
process that needs a steady supply of oxygen.
9.
Write balanced chemical equations for both types of anaerobic respiration.
Glucose  Lactic acid + energy
C6H12O6  2C3H6O3 + energy
10.
Explain why the levels of lactic acid in a person:
A)
Increases when they vigorously exercise
From my understanding lactic acid is produced during exercise because of the
build up that is demanded during anaerobic respiration. Energy is not
supplied fast enough so lactic acid is made and must be removed quickly.
B)
Drop after exercise
Lactic acid is then converted into pyruvate molecules and can then be removed
via ‘normal’ aerobic respiration.
11.
Why do you keep breathing heavily even after you have stopped
running?
If oxygen becomes available this energy can then be released in a subsequent
reaction. Lactic acid is then converted to pyruvate molecules which can then
react with oxygen. Energy is released to be stored in ATP. That is why you
continue to breathe heavy and deep after exercised if finished.
12.
13.
List two industrial uses of the anaerobic respiration of yeast.
- Alcohol: Beer, wine, champagne
What causes the bubbles in champagne?
Enzymes are used to convert yeast to glucose and ethanol. AKA fermentation is
carried out in sealed bottles, which trap the bubbles of carbon dioxide. When the
lid of the bottle is taken off pressure drops and dissolved carbon dioxide bubbles,
which causes the mess during opening the champagne bottle.
Comparing aerobic and anaerobic respiration
14.
Compare the amount of energy released by aerobic and anaerobic
respiration.
It is clear that aerobic respiration releases much more energy than anaerobic
respiration. Because ethanol still contains a store of energy.
Energy sources and uses
15.
List 5 substances from which glucose can be obtained
-Foods and drinks that actually contain glucose
-The conversion into glucose of a substance called glycogen
-The conversion into glucose of protein
-Starchy foods in diet
-Sugary foods and drinks
Metabolism
16.
A. What is meant by the basal metabolic rate (BMR) of a person?
BMR is the minimum energy on which your body can survive on. Your body needs
lots of energy to maintain basic body procedures.
B.
State two factors on which the BMR depends.
-Age
-Sex
-Size
-State of Health
17.
State three reasons why you need energy even when you are resting.
Thinking Question
18.
Why could respiration be called ‘slow combustion’?
Slow combustion is a form of combustion which takes place at low temperatures.
Respiration is a form of slow combustion because the same chemical reaction
takes place in your body. For example it combines with oxygen to release and
make energy.
19.
Enzymes have complex three-dimensional shapes which are altered
by high temperatures. Why does this alteration of shape cause the enzyme to
stop functioning?
Because heat changes the shape of enzymes which results to them and how they
lock into each other. If protein and an enzyme need to lock into each other it is
important that the enzyme is in the right shape to lock with eachotehr. Heat can
alter the size causing other things to lock into it correctly.
20.
When people do not have enough food, they first lose body fat. They
then dangerously lose muscle. Explain why each stage occurs in terms of energy
use and storage.
If glucose is not available energy can be obtained from body fats.