HIGHER HUMAN BIOLOGY: UNIT ONE
HIGHER HUMAN BIOLOGY
Unit 1: Cell Function and Inheritance
Homework Booklet
Name
Teacher
Homework
HW 1: Proteins
HW 2: Nucleic Acids
Section C Questions
HW 3: Aerobic Respn
HW 4: Anaerobic Respn
Section C Questions
HW 5: Cell Membranes
HW 6: Cell Defence
HW 7: Viruses
Section C Questions
HW8: Meiosis/ Mono
Inheritance
HW 9: Sex linked
inheritance &
Incomplete Dominance
HW 10: Mutations
Section C Questions
Date
Due
Parental
Signature
Teacher’s Comment
HIGHER HUMAN BIOLOGY: UNIT ONE
Sub-Unit 1A: Proteins
Homework 1: Structure of proteins and Enzymes
Question 1
The diagram shows part of an enzyme molecule.
P represents a molecule in the chain which forms the primary structure of the
protein.
Q is a bond which links these molecules.
R is a bond which maintains the secondary structure of the protein.
(a) (i) Identify molecule P.
(1)
(ii) Name bonds Q and R.
Q
R
(2)
(b) (i) Why are some digestive enzymes produced in an inactive form?
(1)
(ii) Give an example of a substance which can act as an enzyme activator?
(1)
HIGHER HUMAN BIOLOGY: UNIT ONE
(c) The table below contains information about the effect of environmental
factors on enzymes. Complete this table.
Factor
Type of change
High temperature
Effect on enzyme
structure
(1)
alters active site
Question 2 The diagram below shows the primary structure of part of a
protein molecule.
(a) Name bond X.
(1)
(b) Describe one way in which the secondary structure of a protein differs
from the primary structure.
(1)
(c) Where in the cell are proteins packaged and processed immediately
before secretion?
(1)
END OF HOMEWORK 1
HIGHER HUMAN BIOLOGY: UNIT ONE
Homework 2: Nucleic Acids
Question 1 The diagram below shows part of a DNA molecule.
(a) (i) On the diagram, draw a circle around one nucleotide.
(1)
(ii) Name parts X and Y.
X
Y
(1)
(b) Name the two DNA bases not shown in the diagram.
and
(1)
(c) (i) State the mRNA codon which would be formed from the triplet of DNA
bases shown.
(1)
(ii) Apart from nucleotides, name another molecule needed for the synthesis
of mRNA.
(1)
HIGHER HUMAN BIOLOGY: UNIT ONE
(d) A DNA molecule was found to contain 15 000 nucleotides.
What is the maximum number of amino acids which could be coded for by
this molecule?
(1)
Question 2 The diagram below represents the process of RNA synthesis.
(a) Where in the cell does this process take place?
(1)
(b) (Name the components X, Y and Z.
X
Y
Z
(2)
HIGHER HUMAN BIOLOGY: UNIT ONE
(c) State the full names of any two different RNA bases shown in the
diagram.
1
2
(2)
(d) Name another substance, not shown in the diagram, which is essential for
RNA synthesis.
(1)
Question 3 The formation of a mRNA strand on a section of a chromosome is
shown in the diagram below.
(a) Give the names of bases 1, 2 and 3.
1
2
3
(1)
(b) The mRNA strand is constructed from free nucleotides.
Name the two molecules which combine with a base to form a mRNA
nucleotide.
1
2
(2)
HIGHER HUMAN BIOLOGY: UNIT ONE
(c) Once completed, the mRNA strand moves into the cytoplasm.
What is the destination?
(1)
(d) Explain why the formation of mRNA strands is essential to cell
metabolism.
(2)
Question 4
The diagram shows the synthesis of a peptide chain.
(a) Name bond X and molecule Y.
Bond X
Molecule Y
(2)
(b) What term is used to describe the triplet code on the tRNA molecules?
(1)
HIGHER HUMAN BIOLOGY: UNIT ONE
(c) Give the abbreviated names of the next four amino acids which will be
attached to complete the peptide chain.
iso
(1)
(d) What sequence of bases on a DNA molecule will code for the amino acid
labelled thr?
(1)
(e) Amino acids are added to the peptide chain at a rate of about 15 per
second.
How long will it take for the complete synthesis of the peptide chain
shown in the diagram above?
s
END OF HOMEWORK 2
(1)
HIGHER HUMAN BIOLOGY: UNIT ONE
Section C Questions
2002 1A
Give an account of DNA under the following headings:
(i)
(ii)
DNA structure
DNA replication
(7)
(3)
(10)
2004 2B
Describe how proteins are assembled from the code on a mRNA strand
(10)
2006 1B
Give an account of enzymes under the following headings:
(i)
(ii)
factors affecting enzyme activity;
activation of enzymes.
(7)
(3)
(10)
HIGHER HUMAN BIOLOGY: UNIT ONE
Sub-Unit 1B: Respiration
Homework 3: Aerobic Respiration
Question 1 The diagram below represents two stages in the chemistry of
respiration in a cell which is respiring aerobically.
(a) Name the 3-carbon compound and the 6-carbon compound.
3C
6C
(2)
(b) Draw a line across the diagram to indicate where this series of reactions
would stop if oxygen were not available.
(1)
(c) State the precise location of the Krebs cycle within the cell.
(1)
HIGHER HUMAN BIOLOGY: UNIT ONE
(d) Complete the table below to name product X and to describe what
happens to each of the products.
Product
Fate of Products
X ______________
Hydrogen
Question 2
(2)
The diagram below summarises a metabolic pathway within a cell.
(a) Name the process which results in the formation of pyruvic acid.
(1)
(b) Name substance Q.
(1)
(c) How many carbon atoms are removed in one turn of the Krebs cycle?
(1)
(d) What is the role of NAD in the process?
(1)
HIGHER HUMAN BIOLOGY: UNIT ONE
(e) Why does the cytochrome system stop when oxygen is absent?
(1)
(f) Substance R is the main product of the cytochrome system.
Where in this metabolic pathway is substance R required?
(1)
END OF HOMEWORK 3
HIGHER HUMAN BIOLOGY: UNIT ONE
Homework 4: Anaerobic Respiration
Question 1 The table below contains three statements about two stages of
cellular respiration.
(a) Complete the table to indicate whether the statements are True (T) or
false (F) for each stage.
Statement
Stages of Respiration
Glycolysis
Cytochrome System
Occurs in the mitochondrion
Releases carbon dioxide
T
F
Uses oxygen
(2)
(b) The diagram below summarises anaerobic respiration in a muscle cell.
(i) Name substance X.
(1)
(ii) Which substance would need to be present for pathway Y to occur?
(1)
(iii) Why is anaerobic respiration considered to be a less efficient process
than aerobic respiration?
(1)
(iv) Glucose is not stored in muscle cells.
Name the carbohydrate which is stored in muscle cells.
(1)
HIGHER HUMAN BIOLOGY: UNIT ONE
Question 2
The diagram shows the role of ATP in cell metabolism.
(a) Complete the diagram by entering the names of the appropriate
substances.
(3)
(b) (i) Name one stage of pathway X and state where it occurs in the cell.
Stage
Location
(2)
(ii) Name the organelle where process Y occurs.
(1)
(c) Describe two ways in which the diagram would be different under
anaerobic conditions
1
2
(2)
(d) Name a respiratory substrate other than glucose.
(1)
HIGHER HUMAN BIOLOGY: UNIT ONE
Question 3
respiration.
Stage X
Reactions in the
cytoplasm
The diagram below shows three stages that occur during aerobic
Stage Y
Reactions in matrix
of mitochondrion
1
2
Stage Z
Reactions in cristae
of mitochondrion
Metabolic products
(a) Name each stage
X
Y
Z
(2)
(b) (i) Arrows 1 and 2 represent the transfer of molecules from one stage to
another. Complete the table to identify these molecules.
Name of molecule
Arrow
1
2
(2)
(ii) Name the two metabolic products of stage Z.
and
(1)
HIGHER HUMAN BIOLOGY: UNIT ONE
(c) The diagram below shows a mitochondrion from a skin cell.
Describe how the structure of a mitochondrion from an active muscle cell would
differ from the one shown. Give a reason for your answer.
Structural difference
Reason
(2)
END OF HOMEWORK 4
HIGHER HUMAN BIOLOGY: UNIT ONE
Section C Questions
2000 2A
Give an account of the roles of lipids in the body.
2006 1A
Give an account of respiration under the following headings:
(i)
(ii)
The role of ATP within the cell:
The use of different respiratory substrates.
(4)
(6)
(10)
HIGHER HUMAN BIOLOGY: UNIT ONE
Sub-Unit 1C: Cells
Homework 5: Cell Membranes and Transport
Question 1
membrane.
The diagram below shows a structural model of the plasma
(a) (i) What term describes this model of the membrane?
(1)
(ii) Identify components X and Y.
X
Y
(1)
(iii) State a possible function of Z.
(1)
(b) Sodium ions can be moved against a concentration gradient across a
membrane.
(i)
Explain what is meant by a concentration gradient across a
membrane.
(1)
(ii)
What term describes the movement of ions against a
concentration gradient?
(1)
HIGHER HUMAN BIOLOGY: UNIT ONE
(iii)
Explain why a shortage of oxygen might lead to a decrease in the
rate of sodium ion movement.
(2)
Question 2 The diagram below shows a section through a nucleus and
associated cell structures.
(a)
(i)
Name organelle X.
(1)
(ii)
What type of substance is manufactured in organelle X?
(1)
(iii)
Give an example of such a substance.
(1)
(b)
(i)
The structure labelled Y is composed of sheets of membranes.
What name is given to this structure?
(1)
HIGHER HUMAN BIOLOGY: UNIT ONE
(ii)
(c)
Structure Y can transport substances to another organelle within
the cell.
Give an example of such an organelle and state its function.
Example
(1)
Function
(1)
Why is it necessary to have pores in the nuclear membrane?
(1)
Question 3
(a)
The table below shows the relative concentrations of sodium and
potassium ions in red blood cells and plasma.
Sodium
Potassium
(units/litre)
(units/litre)
red blood cells
24
150
plasma
144
5
(i)
Express, as a simple ratio, the concentrations of sodium ions and
potassium ions in the red blood cells and plasma.
Space for Calculation
(ii)
(1)
Sodium
(2)
potassium
Red blood cells
:
plasma
:
:
(1)
Suggest how the red blood cells maintain the potassium
concentration gradient.
(1)
HIGHER HUMAN BIOLOGY: UNIT ONE
(iv)
When glucose is in short supply, the concentration of potassium in
the red blood cells changes.
State whether the concentration will increase or decrease and give a
reason for your answer.
Increase/decrease
Reason
(2)
(b)
Three samples of red blood cells were placed in different concentrations
of sodium chloride solution for two minutes. The results of this
treatment, when viewed under the microscope, are shown in the diagram
below.
Using the information above, explain the appearance of the cells in each diagram.
A
B
C
(2)
END OF HOMEWORK 5
HIGHER HUMAN BIOLOGY: UNIT ONE
Homework 6: Cellular Defence
Question 1 The diagram below shows the sequence of events as a white blood
cell engulfs and destroys a bacterium.
(a) Name the structures A, B and C.
A
B
C
(b) (i)
(2)
What is the name given to this process of engulfing bacteria
(1)
(ii)
Describe the roles of structures B and C in the cell.
B
(1)
C
(1)
(c) What does the lysosome contain?
(1)
HIGHER HUMAN BIOLOGY: UNIT ONE
Question 2
response.
(a)
The diagram below shows three stages in the humoral immune
(i) What type of white blood cell carries out the humoral immune
response?
(1)
(ii) What name is given to foreign molecules which stimulates the immune
response?
(1)
(b)
Describe two responses made by the white blood cell as a result of the
attachment of the foreign molecules.
1
2
(1)
END OF HOMEWORK 6
HIGHER HUMAN BIOLOGY: UNIT ONE
Homework 7: Viruses
Question 1 The diagram below represents the structure of the virus which
causes influenza.
(a)
(i)
Name the substance which makes up the coat of this virus.
(1)
(ii)
Describe how a virus from an influenza vaccine might differ in
structure from the virus shown in the diagram.
(1)
(b)
The following diagrams show a cell being attacked by the influenza virus.
(i) Describe how the virus reproduces over the two day period.
(2)
HIGHER HUMAN BIOLOGY: UNIT ONE
(ii) State how viruses are released from the infected cell.
(1)
(c)
There are three main types of influenza virus.
Why are the antibodies produced against one type not effective against
the others?
(1)
Question 2 The diagrams below show a disease-causing virus and one of the
same type which has been weakened to make it less harmful.
(a)
A woman is vaccinated with the weakened form of the virus.
(i)
Explain why she does not develop the disease from the vaccination.
(1)
(ii)
What feature of the weakened virus results in her gaining
immunity from the disease?
(1)
HIGHER HUMAN BIOLOGY: UNIT ONE
(iii)
Explain why this form of immunity is described as being both
artificial and active.
Artificial
(1)
Active
(1)
(b)
The table below contains information about viruses.
Tick (√) the appropriate boxes to show characteristics which apply to all
viruses.
Characteristic
Tick
(√)
Contains a nucleus
Surrounded by a protein coat
Can be seen by a light microscope
Contains nucleic acid
Can only reproduce inside another cell
Question 3
(a)
(2)
The diagram shows a polio virus.
Viruses can only reproduce within a host cell.
(i)
List two substances, supplied by a host cell, which are required for
viral replication.
1
2
(1)
HIGHER HUMAN BIOLOGY: UNIT ONE
(ii)
What happens after the viruses have been assembled inside the
cell?
(2)
(b)
Viruses can be processed to make vaccines to protect against the disease.
Suggest why it is important that the nucleic acid is damaged in the
process, but not the protein coat.
Nucleic acid damaged
(1)
Protein coat
undamaged
(1)
(c)
The average diameter of a red blood cell is 7 μm.
By how many times is a red blood cell bigger than a polio virus? (1μm =
1000nm)
Space for calculation
(1)
END OF HOMEWORK 7
HIGHER HUMAN BIOLOGY: UNIT ONE
Section C Questions
2001 1B
Give an account of immunisation under the following headings:
(i)
(ii)
Artificial active immunity;
Artificial passive immunity
(6)
(2)
(8)
* additional (iii) on vaccination against childhood diseases from Unit 3 (for 2
marks)
2002 1B
Give an account of immunity under the following headings:
(iii)
(iv)
B-lymphocytes and T-lymphocytes;
Macrophages
(7)
(3)
(10)
HIGHER HUMAN BIOLOGY: UNIT ONE
Sub-Unit 1D: Inheritance
Homework 8: Meiosis and Monohybrid Inheritance
Question 1 Some stages in the process of meiosis are shown in the diagram
below.
Only 6 of the chromosomes are shown in each cell.
(a)
(i)
Place the stages in the correct order.
(1)
(ii)
At which stage would the chiasmata form?
(1)
(iii)
Why are chiasmata important?
(1)
(b)
The diagram below shows a gamete mother cell and four sperm which
would result from meiosis.
(i) Complete the diagram by writing in the normal number of chromosomes
found in each of the cells.
(1)
HIGHER HUMAN BIOLOGY: UNIT ONE
(ii) In how many of these sperm will an X chromosome be found?
(1)
Question 2
in a family.
(a)
(i)
The diagram below shows the inheritance of tongue-rolling ability
Using the symbol R to represent the allele for tongue-rolling, and
the symbol r to represent the non tongue-rolling, state the
genotypes of P and T.
P
(ii)
T
(1)
How many individuals, shown in the family tree, have a genotype
which is homozygous recessive?
(1)
(iii)
Place a cross through a symbol in the family tree which represents
a heterozygous male.
(1)
(iv)
Female S is pregnant. Using information from the family tree, is
it possible to predict whether the child will be a tongue-roller or
not?
Give a reason for your answer.
YES/NO
Reason
(1)
HIGHER HUMAN BIOLOGY: UNIT ONE
(b)
Some characteristics are controlled by several genes.
(i)
State the term used to describe this type of inheritance pattern.
(1)
(ii)
Which two of the following human characteristics show this type
of inheritance pattern? Underline the correct answers.
(1)
blood groups
cystic fibrosis
haemophilia
Question 3
height
skin colour
The family tree shows the inheritance of a bone disorder.
The disorder is caused by a dominant sex-linked allele (B).
(a)
Using appropriate symbols, give the genotypes of individuals P, Q, R and
S.
p
(b)
Q
(i)
R
S
(2)
Explain why all the females in the F1 generation are affected.
(1)
HIGHER HUMAN BIOLOGY: UNIT ONE
(ii)
Explain why only some of the females in the F2 generation are
affected.
(1)
(c)
Is the ratio of affected offspring to unaffected offspring in the F1
generation as expected? Give a reason for your answer.
YES/NO
Reason
(1)
END OF HOMEWORK 8
HIGHER HUMAN BIOLOGY: UNIT ONE
Homework 9: Sex-linked inheritance and Incomplete Dominance
Question 1 Polydactyly is an inherited condition in which individuals are born
with extra toes. The allele for polydactyly is dominant and not-sex-linked.
The family tree below shows the incidence of the condition through three
generations.
(a)
(i)
Using the symbol D for the allele for polydactyly and d for the
normal allele, give the genotypes for the two children.
and
(ii)
(1)
Individuals X and Y are expecting another child.
What are the chances of this child inheriting the condition?
(1)
(b)
(i)
What evidence from the family tree confirms that the
grandfather is heterozygous?
(1)
(ii)
What evidence from the family tree confirms that the
condition is not sex linked?
(1)
(c)
What term is used to refer to chromosomes which are not sexchromosomes?
(1)
HIGHER HUMAN BIOLOGY: UNIT ONE
Question 2 Thalassaemia is an inherited blood disorder in which haemoglobin
is affected. The condition illustrates incomplete dominance in which the
recessive allele has a partial effect. Heterozygous individuals show mild
symptoms.
The diagram below shows the incidence of thalassaemia in three generations of a
family.
(a)
Using the symbol HbA to represent the allele for normal haemoglobin,
and the symbol HbB to represent the recessive allele, complete the table
to show the genotypes of Anne, Philip and Charles.
Individual
Genotype
Anne
Philip
Charles
(2)
(b)
Mark and Carla have a third child. What is the percentage chance that
the child will have the same genotype as the parents?
Space for calculation
%
(1)
HIGHER HUMAN BIOLOGY: UNIT ONE
Question 3 Sickle cell anaemia is a blood disorder in which haemoglobin is
malformed.
The diagram below shows the effect of this disorder on a red blood cell.
The condition is not sex-linked. The allele for normal haemoglobin (H) is
incompletely dominant to the sickle-cell allele (h).
Heterozygous individuals are mildly affected, whereas those with genotype hh
are severely affected.
Two mildly affected parents have two children who are mildly affected like their
parents. The parents are expecting a third child.
(a)
Complete the Punnett square to show the possible genotype of this child.
(2)
(b)
From the Punnett square calculate the percentage chance of the child
being
1
unaffected
2
mildly affected
3
severly affected
END OF HOMEWORK 9
(2)
HIGHER HUMAN BIOLOGY: UNIT ONE
Homework 10: Mutations
Question 1 Achondroplasia is an autosomal disorder of bone growth that is
caused by a gene mutation. A person with this condition has relatively short
arms and legs.
The incidence of achondroplasia in a family is shown in the diagram below.
(a)
(i)
In this family, the mutation has occurred in the ovum.
In which individual did the mutation take place?
(1)
(ii)
Describe a change which takes place in a gene when it mutates.
(1)
(b)
The allele which causes achondroplasia is dominant.
What is the percentage chance that a child of H and J would inherit
achondroplasia>
Space for calculation
%
(1)
HIGHER HUMAN BIOLOGY: UNIT ONE
(c)
The list below contains a number of inherited disorders.
Phenylketonuria
Down’s Syndrome
Haemophilia
Huntington’s chorea
Cystic fibrosis
Select a disorder from the list which is:
(i)
The result of non-disjunction
(ii)
A sex-linked condition
END OF HOMEWORK 10
Section C Questions
2004 2A
Describe the events in meiosis which give rise to variation in gametes
(10)
(2)