Download Unit 1 – Human Cells Key Areas 1

Unit 1 – Human Cells
Key Areas 1-3
HOMEWORK BOOKLET
Name: _________________________________________
Homework
Key Area 1
Division and differentiation
in human cells
Key Area 2
Structure and replication of
DNA
Key Area 3
Gene Expression
Date Due
Mark
MCQ:
Section B:
Essay:
TOTAL:
MCQ:
Section B:
Essay:
TOTAL:
MCQ:
Section B:
TOTAL:
%
/7
/8
/10
/25
/12
/5
/5
/22
/7
/24
/31
Key Area 1 – Division and differentiation in human cells
1. Which of the following is not a use of stem
cells?
A.
B.
C.
D.
5. Which of the following statements regarding
stem cells is TRUE?
Skin grafts
Drug testing
IVF treatment
Bone marrow transplant
A. Stem cells are specialised cells that
continue to divide.
B. Stem cells cannot differentiate into
specialised cells
C. Stem cells are unspecialised cells that
can differentiate into specialised cells.
D. None of the above
2. Which line in the table below describes
correctly cell division in a specific cell type?
Type of
Chromosome
Cell Type
cell
number in cells
division
produced
A
somatic
meiosis
diploid
B
somatic
meiosis
haploid
C germline mitosis
haploid
D germline mitosis
diploid
6. Cancer cells can divide excessively to produce
a mass of abnormal cells known as a tumour.
A tumour cell can double every 40 minutes. If
one tumour cell starts to divide how many
tumour cells will be present after 12 hours?
A.
B.
C.
D.
3. Which of the following statements about
cancer cells is TRUE?
720
32768
131072
262144
7. The cell shown below is magnified six
hundred times. What is the actual size of the
cell?
A. Cancer cells respond to regulatory
signals
B. Cancer cells cannot spread through
the body
C. Cancer cells cannot divide excessively
D. Cancer cells can form secondary
tumours
4. Which of the following statements is TRUE?
A.
B.
C.
D.
A. Blood cells and muscle cells are
undifferentiated germline cells
B. Blood cells and muscle cells are
differentiated germline cells
C. Blood cells and muscle cells are
undifferentiated somatic cells
D. Blood cells and muscle cells are
differentiated somatic cells
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1080 μm
108 μm
30 μm
3 μm
8.
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9. List 3 therapeutic uses of stem cells.
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(2)
10. Tumours can be found in patients suffering from cancer.
(a) Describe what a tumour is
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(b) Describe how a secondary tumour develops
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11. Give an account of cell differentiation under the following headings:
a. Stem cells (4 marks)
b. Somatic cells (4 marks)
c. Germline cells (2 marks)
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[END OF HOMEWORK]
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Key Area 2 – Structure and Replication of DNA
1. A DNA molecule consists of 4000 nucleotides
of which 20% contain the base adenine.
How many of the nucleotides in this DNA
molecule will contain guanine?
A. 800
B. 1000
C. 1200
D. 1600
6. How many adenine molecules are present in a
DNA molecule of 4000 bases, if 20% of the
base molecules are cytosine?
A. 400
B. 600
C. 800
D. 1200
7. Which of the following statements about DNA
replication is correct?
A. Polymerase adds nucleotides to the 3’
end of a DNA strand
B. Polymerase adds nucleotides to the 5’
end of a DNA strand
C. Ligase adds nucleotides to the 3’ end
of a DNA strand
D. Ligase adds nucleotides to the 5’ end
of a DNA Strand
2. A fragment of DNA was found to have 120
guanine bases and 60 adenine bases. What is
the total number of sugar molecules in this
fragment?
A. 60
B. 90
C. 180
D. 360
3. If ten percent of the bases in a molecule of
DNA are adenine, what is the ratio of adenine
to guanine in the same molecule?
A. 1:1
B. 1:2
C. 1:3
D. 1:4
8. Thirty percent of bases in a DNA molecule are
adenine. The percentage of cystosine bases
in the same molecule is:
A. 20%
B. 30%
C. 40%
D. 70%
4. A DNA nucleotide could be formed from a
molecule of phosphate together with
A. Ribose sugar and guanine
B. Ribose sugar and uracil
C. Deoxyribose sugar and guanine
D. Deoxyribose sugar and uracil
9. If the mass of DNA in a human liver cell is 6.6
x 10-12g, the mass of DNA in a human sperm is
likely to be:
A. 3.3 x 10-6g
B. 3.3 x 10-12g
C. 6.6 x 10-6g
D. 6.6 x 10-12g
5. If a DNA molecule contains 8000 nucleotides
of which 20% are adenine, then the number
of guanine nucleotides present is:
A. 1600
B. 2000
C. 2400
D. 3200
10. The two components which make up the
backbone of each DNA strand are:
A. Ribose and phosphate group
B. Deoxyribose and base pairs
C. Deoxyribose and phosphate group
D. Phosphate group and thymine
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11. Which of the following diagrams correctly
represents part of a DNA molecule?
The letters A, T, U, C and G represent bases.
A.
3’
5’
B.
3’
C.
5’
D.
3’
A
C
T
A
T
T
A
C
U
A
C
G
3’
5’
12. Which of the following statements about the
structure of DNA is TRUE?
A. In DNA the base pairs are held together by
peptide bonds.
B. Fragments of DNA are joined together by
polymerase
C. Fragments of DNA are joined together by
polymerase
D. DNA contains the bases represented by
the letters A, U, C and G.
5’
13.
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14. Name the 2 enzymes involved in DNA replication and state the function of each one.
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15. Give an account of the replication of DNA (5 marks)
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[END OF HOMEWORK]
Page 8
Key Area 3 – Gene Expression (TASK 1)
1. The function of tRNA in cell metabolism is to :
A. Transport amino acids to be used in
synthesis
B. Carry codons to the ribosomes
C. Synthesise proteins
D. Transcribe the DNA code
4. The table below contains statements which
may be TRUE or FALSE with regard to DNA
replication and mRNA synthesis.
Which line in the table is correct?
Statement
2. The following information refers to protein
synthesis.
tRNA anticodon
GUG
CGU
GCA
AUG
UAC
UGU
DNA
mRNA
Replication synthesis
Occurs in the
nucleus
Involved in
B
protein
synthesis
Requires free
C
nucleotides
Involves
D specific base
pairing
A
amino acid carried
by tRNA
Histidine (his)
Alanine (ala)
Argomome (arg)
Tyrosine (tyr)
Methionine (met)
Threonine (thr)
TRUE
FALSE
TRUE
TRUE
TRUE
FALSE
TRUE
TRUE
5. The diagram represents part of a molecule of
DNA on which a molecule of RNA is being
synthesised.
What order of amino acids would be
synthesised from the base sequence of DNA
shown?
Base sequence of DNA:
C G T T A C G T G
A.
B.
C.
D.
arg
ala
ala
arg
-
tyr met tyr
tyr
-
his
his
his
thr
What does component X represent?
A.
B.
C.
D.
3. DNA controls the activities of a cell by coding
for the production of:
A. Proteins
B. Carbohydrates
C. Amino acids
D. Bases
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Ribose sugar
Deoxyribose sugar
Phosphate
Ribose phosphate
6. A section of DNA has the following base
sequence
A A T C G C T T C
7. The mRNA codon for the amino acid
theronine is ACU. What is the corresponding
anti-codon?
A.
B.
C.
D.
Identify the anti-codons of the three tRNA
molecules which would align with the mRNA
molecule transcribed from this section of
DNA.
A.
B.
C.
D.
AAU
AAT
TTA
UUA
CGC
CGC
GCG
GCG
UUC
TTC
AAG
AAG
8.
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ACT
UCT
UGA
TGA
9.
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10.
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11.
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12.
[END OF HOMEWORK]
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