Download Biology

GCSE to AS Biology…
In this pack you will find:
 An introduction to A-level Biology
 A copy of the AS Specification
 Information on the 1st topic covered at AS
 2 tasks (presentation and exam questions)
 Useful websites
 Success criteria for the presentation
An introduction to AS Biology:
 Syllabus: Edexcel Salters-Nuffield Biology AS
 2 exams (Unit 1 6BI01 and Unit 2 6BI02)
 Coursework (Unit 3 6BI03): Assessed on core practicals written up during the course and an issue
report.
Topic 1

The first unit that we will study in September is Lifestyle and Risk
To prepare you for AS Biology you will need to revise some of the GCSE work that you have covered
in Biology. This will be from B2 (Keeping Healthy) and C3 (Food Matters)
Your task:
1. To prepare a short presentation (5-7) minutes on one of the following topics:
a. The structure and function of the heart
b. The structure and function of blood vessels – arteries, veins and capillaries
c. The chemical structure of carbohydrates
d. The chemical structure of lipids
2. To answer the attached exam questions


You will need to revise B2 and C3 (use your notes, revision guide, SAM learning, BBC bitesize).
Here are a list of useful websites:
 www.s-cool.co.uk
 www.biologyguide.net
 www.biologymad.com
 www.biology-innovation.co.uk
What to include in your presentation:
Topic
The structure and function of the heart
Specification points
Explain why many animals have a heart and
circulation.
Describe the cardiac cycle (atrial systole,
ventricular systole and diastole) and relate the
structure and operation of the mammalian
heart to its function.
The structure and function of blood
vessels – arteries, veins and capillaries
The chemical structure of carbohydrates
Explain how the structures of blood vessels
(capillaries, arteries and veins) relate to their
functions.
Distinguish between monosaccharides,
disaccharides and polysaccharides (glycogen
and starch – amylase and amylopectin) and
relate their structures to their roles in
providing and storing energy.
Describe how monosaccharides join to form
disaccharides (sucrose, lactose and maltose)
and polysaccharides (glycogen and amylase)
through condensation reactions forming
glycosidic bonds and how these can be split
through hydrolysis reactions.
Describe the synthesis of a triglyceride by the
formation of ester bonds during condensation
reactions between glycerol and three fatty
acids and recognise differences between
saturated and unsaturated lipids.
The chemical structure of lipids
Answer the following:
1.
The table below refers to two disaccharides, sucrose and maltose. If the statement is correct,
place a tick ( ) in the appropriate box and if the statement is incorrect, place a cross ( ) in the
appropriate box.
Statement
Sucrose
Maltose
Contains glucose
Is a reducing sugar
Contains glycosidic bonds
Is transported in the phloem
of flowering plants
(Total 4 marks)
2.
The table below refers to some disaccharides, their constituent monomers and their roles in
living organisms.
Complete the table by writing in the appropriate word or words in the empty boxes.
Disaccharide
Constituent monomers
One role in living
organisms
Carbohydrate source in
mammalian milk
Lactose
Glucose + glucose
Form in which sugars
are transported in
plants
(Total 5 marks)
3.
Starch is a storage carbohydrate found in plants. Starch is composed of many α-glucose
molecules that bond together by condensation reactions.
(a)
The diagram below shows the structure of α-glucose.
(i)
In the space below, draw a diagram to show the products formed when two αglucose molecules join together by means of a condensation reaction to form
maltose.
(3)
(ii)
Name the bond that joins the two α-glucose molecules together.
...........................................................................................................................
(1)
(b)
Describe the structure of starch and explain why this structure makes it a suitable
molecule for storing energy.
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(4)
(Total 8 marks)
4 (a) The diagram below shows the structure of a triglyceride.
Ch2 O
Bond A
CHO
CH2 O
O
C
O
C
O
C
triglyceride
(i)
Name Bond A on the diagram.
...........................................................................................................................
(1)
(ii)
Name the type of reaction that will break down the triglyceride into its constituent
parts during digestion by lipase enzymes.
...........................................................................................................................
(1)
(iii)
Name two products formed when triglycerides are completely digested.
1 ........................................................................................................................
2 ........................................................................................................................
(2)
(iv)
Some triglycerides have several double bonds (C C), others have none.
Describe one way in which the physical property of triglycerides which include
several double bonds will differ from triglycerides which have no double bonds.
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(1)
5
The diagram below shows cross-sections of three different types of blood vessel, A, B and C.
A
B
5 mm
(a)
C
5 mm
0.005 mm
Name the blood vessels A and B.
A ...............................................................................................................................
B ...............................................................................................................................
(1)
(b)
State two ways in which blood vessel C is adapted to enable the formation of tissue fluid.
1 ................................................................................................................................
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2 ................................................................................................................................
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(2)
(c)
Give one function of tissue fluid.
……………………………………………….………………………………………
(1)
(d)
When tissue fluid is not efficiently reabsorbed, it collects in tissues causing swelling
(oedema). Suggest one factor that could cause oedema.
……………………………………………….………………………………………
……………………………………………….………………………………………
(1)
(Total 5 marks)
6 The diagram below shows a transverse section of a blood vessel, as seen using low magnification of a light
microscope.
A
(a)
Name the type of blood vessel shown in the diagram.
.....................................................................................................................................
(1)
(b)
The layer labelled A contains smooth muscle fibres, collagen and elastic fibres.
(i)
Name layer A.
...........................................................................................................................
(1)
(ii)
Describe the function of the collagen fibres.
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(2)
7 The diagram below shows the structure of the heart and some associated blood vessels.
(a)
Name the parts labelled A, B and C.
A ...................................................................................................................................
B ...................................................................................................................................
C ...................................................................................................................................
(2)
(b)
Describe how the structure of the left ventricle and the parts labelled B and C enable
the left ventricle to carry out its function.
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(4)
(c)
Many organs such as the uterus, heart and kidneys of a pregnant woman use more
oxygen than when she is not pregnant. The graph below shows the increased usage of
oxygen by these organs near the end of pregnancy, as compared with the oxygen used
before pregnancy.
8
7
6
Increase in 5
oxygen used
/ cm3 min–1 4
3
2
1
0
Uterus
Heart
Kidneys
Suggest why the use of oxygen by each of the following organs increases during
pregnancy.
(i)
Uterus
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(ii)
Heart
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(4)
(Total 10 marks)
8 (a) The diagram below shows a ventral (front) external view of a mammalian heart.
X
Y
Z
(i)
Name the structures labelled X, Y and Z.
X .......................................................................................................................
Y .......................................................................................................................
Z .......................................................................................................................
(3)
(ii)
There are four boxes on the heart diagram. Place a tick (�) in the box that correctly
identifies the position where electrical activity of the heart is initiated.
(1)
(iii)
Name the structure that initiates electrical activity in the heart.
...........................................................................................................................
(1)
(b)
Blood pressure within the heart varies throughout the cardiac cycle.
(i)
Explain what is meant by the term cardiac cycle.
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(2)
(ii)
The table below shows the range of blood pressures found in the left ventricle and
in the right ventricle during one complete cardiac cycle.
Ventricle
Blood pressure / kPa
Right
0.0 to 3.3
Left
0.0 to 15.8
Explain why the maximum blood pressure is higher in the left ventricle than in the
right ventricle.
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(2)
(iii)
Explain why blood pressure varies in a ventricle during the cardiac cycle.
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(2)
(c)
Apart from high blood pressure, state two other risk factors for heart disease.
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(1)
(Total 12 marks)
9.
The figure below shows a simplified diagram of the heart.
(i)
Draw arrows on the diagram to show the direction of blood flow through both sides of the
heart during diastole.
(1)
(ii)
Name the part of the heart responsible for the initiation of the cardiac cycle.
.....................................................................................................................................
(1)
(Total 2 marks)
10.
The diagrams below show the left side of the heart at two stages of the cardiac cycle.
X
Diagram A
(a)
(i)
Diagram B
Name structure X shown on the diagram.
X .......................................................................................................................
(1)
(ii)
Name the part of the cardiac cycle illustrated by diagram B.
...........................................................................................................................
(1)
(iii)
With reference to structures shown on diagram B, describe and explain what
happens during this phase of the cardiac cycle.
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(3)
(b)
Balloon angioplasty is regularly used to unblock coronary arteries that have been affected
by atherosclerosis. The procedure is shown in the diagram below.
Guiding catheter
Narrowed coronary artery
Balloon catheter with
uninflated balloon
Balloon catheter with
partially inflated balloon
Balloon catheter with
inflated balloon
Unblocked coronary artery
(i)
Suggest why the patient may experience chest pain as a result of this partial
blocking of one of the coronary arteries.
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(3)
(ii)
Suggest why the walls of the artery return to their original position once the balloon
is removed.
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(1)
(c)
Explain why doctors may advise a patient to try a balloon angioplasty in preference to an
operation such as a coronary bypass.
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(2)
(d)
Suggest why atherosclerosis usually affects coronary arteries but not coronary veins.
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(1)
(Total 12 marks)