Biogenetics Flashcards
(23 cards)
Give one effect that smoking can have on the body. [1]
Imcreased risk of heart disease. [1]
Give two reasons as why energy is transferred from respiration. [2]
To build up larger molecules from smaller ones. [1]
It is used to allow the muscles to contract [1]
Whats the definition of anerobic respiration?[1]
It’s the incomplete breakdown of glucose, making lactic acid.
Why is anaerobic respiration not as efficient as aerobic respiration? [1]
Because it releases a toxic chemical in the muscle called lactic acid.
What are the products of anaerobic respiration in plants and yeast?[1]
Ethanol and carbon dioxide.
What is photosynthesis?[1].
It uses energy to change carbon dioxide and water into glucose and oxygen.
Why does your heart rate increase during exercise?. [2]
To get more oxygenated blood around the muscles faster which removes CO2 more quickly at the same time.
Give two reasons why the breathing rate increases as you exercise?[2]
To supply more oxygen into the blood and to remove carbon dioxide.
Why does anaerobic respiration occur in the body?[1]
When you can’t supply enough oxygen to your muscles. [1]
How do you investigate the effect of exercise on the body. [6]
Have at least 5 people in a group.
The control variable is their age and gender.
Measure each person’s heart rate before and after excerise.
Make each person jog and run and calculate the increase in heart rate for each person after excerise.
Plot your results in a graph.
Compare results for each person
Describe how a student would find out if a liquid extracted from the leave contains glucose.[3]
Add benedict’s solution, heat it, and if glucose is present the blue colour changes to yellow.
Describe how a student would find out if the liquid from the leaf contained starch. [2]
Add a drop of iodine solution and if the strach is present it changes colour to blue.
Explain why excess glucose in the plant is stored as starch. (2)
Because strach is insoluble [1] and a cell with lots of glucose would draw in loads of water and swell up. [1)
Explain why the leaf in the light for four days contained both glucose and starch?. [2)
Glucose made from photosynthesis [1]which causes excess glucose converted to strach. [1]
A man is running in a park.
Explain why the man’s breathing rate increased when he was running. [2]
Because he gets more oxygen (into the blood).
To use in respiration or for releasing energy for ( muscle contraction).
Describe two differences between aerobic respiration and anaerobic respiration in humans. [2]
Anaerobic respiration produces lactic acid and aerobic respiration does not.
Aerobic respiration produces carbon dioxide and water but anerobic does not.
Can plants and yeasts cells aerobically respire?
What do they produce during the process.
[2]
Yes, they both can respire.(1)
In the presence of oxygen yeast and plant cells breakbdown glucose into carbon dioxide and water releasing more energy than anerobic respiration.[1]
Explain why the leaf left in a cupboard with no light for two days did contain glucose but did not contain starch. [3]
Starch have been converted to glucose.[1]
So the glucose can be used for respiration.[1)
Because there is no light to make glucose by photosynthesis. [1]
Suggest two ways the method to investigating photosynthesis using pondweed would improve results so they can become more valid.
Repeat and calculate the mean.[1]
Control the concentration of carbon dioxide.[1]
How would you investigate the effect of light intensity on the rate of photosynthesis?.
The image below shows some of the apparatus you might use like pondweed, beaker, ruler and lamp.
You should include details of:
How would you set up the apparatus and the materials you would use.
The measurements you could make.
How could you make the test fair. [6]
Place a peice of pondweed in a beaker of water and shine a lamp in it from a set distance.
Vary the light intensity by changing the distance of the lamp from the plant, make sure to wait a few minutes at each distance to allow the plant to adjust.
Measure the rate of photosynthesis by counting the number of oxygen needed by a gas in a syringe.
Keep control variables such as the same species of pondweed.
