Biology June 2017 Higher Tier Unit 1 Past Paper Questions Flashcards
The table gives information about food molecules. (See screenshots)
Complete the table.
(List smaller Molecules that make up Food Molecules and their main function in the body)
(4 marks)
Carbohydrates: Sugar/glucose - Energy source/respiration.
Fats: Fatty acids and glycerol - (Energy store)
Proteins: Amino acids - (Growth and Repair)
The diagram shows part of a food web found in a woodland. (See screenshots)
a) Describe the role of plants in this food web.
(3 marks)
Plants are Producers - Use (trap/absorb) energy from sunlight for photosynthesis; make their own food.
- Provide food/energy for animals in food web.
The diagram shows part of a food web found in a woodland. (See screenshots)
In this woodland, Disease killed many Red Squirrels.
(b) Explain how this would affect the number of Field Mouse.
(2 marks)
Give one of: Field mice decrease; - More eaten by hawk, fox and weasel. or Field mice increase; - due to less competition (from red squirrels)/more food; or Field mice stay the same; - more food but more predation.
The photograph shows how a plant responds to light from one direction. (See screenshots)
Look at the photograph.
Name the plants response to light (bending towards light).
(1 mark)
Phototropism
The Hormone Auxin causes the plant to bend.
Explain how.
(2 marks)
Shoot tip is sensitive to light and produces uneven distribution of Auxin which accumulates on the shaded side
- (Auxin) causes cells on this side to elongate faster than the illuminated side in differential growth.
The stem bends towards light.
Suggest why this response (Phototropism) may benefit the plant.
(2 marks)
Phototropism may benefit the plant as it allows more light to be absorbed for photosynthesis and Plant growth.
A class of students set up an investigation into the effect of amylase and lipase Enzymes on starch solution.
They set up two test tubes each containing 5cm^3 of starch solution.
They added 2cm^3 of amylase solution to tube A.
They added 2cm^3 of lipase solution to tube B.
The students then placed Tubes A and B in a water bath at 35°C for 30 minutes.
After 30 minutes the students added 5 drops of iodine to each tube.
The colour solution in each tube was recorded.
The table shows their results. (See screenshots)
Explain the results for Amylase and Lipase.
Use your knowledge of Enzyme structure and action to support your answer.
(In this question you will be assessed on your written communication skills, including the use of specialist scientific terms.)
(6 marks)
The colour changes in tube A from Blue/Black to yellow/brown, showing Amylase breaks down starch.
- Amylase has an active site (/ molecule) shape that complimentary to the Starch substrate which allows the reaction to catalyse and break down the starch into Simple Sugars.
- Lipase (tube B) remains blue/black showing starch is still present and has not been digested as it cannot be broken down by Lipase.
- Lipase’s Active site is of a different shape and unlike Amylase does not fit starch.
- Similar to a key, an Enzymes Active site only fits into specific locks which allows the Starch to easily connect to the Amylase but not the Lipase. This connection is known as the Lock and Key model.
- This demonstrates Enzyme Specificity.
Explain the results for Amylase and Lipase (how it reacts when added to a solution of starch)
Use your knowledge of Enzyme structure and action to support your answer.
(In this question you will be assessed on your written communication skills, including the use of specialist scientific terms.)
(6 marks)
Simplified
- colour change in tube A to yellow/brown;
- shows amylase breaks down starch (into simple sugars);
- amylase has active site (/ molecule) shape that fits (/complimentary) with
starch; - lipase/tube B remains blue/black showing starch still present/not digested;
- lipase has (active site which is) different shape/does not fit starch;
- result demonstrates enzyme specific(ity);
- appropriate reference to lock and key model;
Accept: bullet points which start with capital letter, contain a verb and end in full stop as sentences.
The table shows the mass of some gases released into the atmosphere between 2009 and 2013 in the UK. (See screenshots)
(a) Give one similarity and one difference in the trend in mass of sulfur dioxide and nitrogen oxides between 2009 and 2013.
(2 marks)
Similarity – both reduce (over the 5 years).
Difference – SO2 reduces continuously, NOX fluctuates/Less NOX than SO2.
Factories and power stations release large masses of Sulfur Dioxide into the atmosphere.
Describe how this Sulfur Dioxide is produced.
(2 marks)
Burning/combustion of fossil fuels (coal/oil).
Describe how Sulfur Dioxide in the atmosphere can lead to acid rain.
(2 marks)
Emitted into the atmosphere, Sulfur Dioxide is transported by wind/air current.
- It the reacts with (/dissolves in) water (vapour) O2 and other chemicals in the clouds to form Sulfuric Acid which makes the rain more acidic than normal.
Describe and explain how acid rain the Biodiversity of a forest ecosystem.
(2 marks)
Acid rain damages the waxy layer on the leaves of trees/plants making it more difficult for trees to absorb the minerals they need for healthy growth. Plants and some trees die as a result.
Biodiversity is reduced as some animals will lose their habitats and many aquatic creatures die as rivers/lakes become too acidic due to acid rainfall.
Classification is used to identify different species of organisms.
(a) What is a Species?
(2 marks)
- Group of organisms with shared features/characteristics/DNA.
- Can interbreed to produce fertile offspring
This key can be used to classify organisms into five kingdoms. (See screenshots)
(4 marks)
- (A) Bacteria: No Nucleus present.
- (B) Protoctista: Nucleus present, Multicellular.
- (C) Animal/Animalia: Nucleus present, Multicellular, Cell Wall present.
- (D) Fungi: Nucleus present, Multicellular, Cell Wall present, Saprophytic.
Give two other uses for classification.
(apart from identifying different species of Organisms)
(2 marks)
Any two from:
• Compare biodiversity
• Conservation of species
• Study how animals have changed over time
