MSB 101
MOI UNIVERSITY
SCHOOL OF MEDICINE
END OF TERM I EXAMINATION (ETE I) 2006/2007
COURSE CODE: MSB 101
COURSE TITLE: CELL BIOLOGY SKIN AND GENETICS
PROGRAMME: M.B.Ch.B. YEAR OF STUDY: 1(ONE)
DATE: 17TH APRIL 2007
TIME: 9.00 A.M. - 12.00 NOON
GENERAL INSTRUCTIONS:(i)
Write your University Registration Number on every piece of paper you use.
(ii)
Do not write your names on any piece of paper you use.
(iii)
This paper consist of four (4) sections, headed Section A: Human Anatomy,
Section B: Biochemistry, Section C: Physiology and Section D: Immunology.
All to be answered in a total time of three (3) hours.
(iv)
For M.B.Ch.B and Nursing students, each section constitutes a Continuous
Assessment Test CAT in the respective discipline.
(v)
Questions in each section must be answered in separate answer booklets or
answer sheets, so that they can be handed in separately at the end of the
examination.
(vi)
Read carefully any additional instructions preceeding each station or
subsection.
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MSB 101
SECTION A: HUMAN ANATOMY (65 minutes)
SUBSECTION AI: MULTIPLE CHOICE QUESTIONS (MCQs) (20 minutes)
TYPE III
INSTRUCTIONS:
(I)
THIS SECTION CONTAINS TWENTY (20) MULTIPLE CHOICE
QUESTIONS (MCQs)
(II)
THERE IS ONLY ONE WRONG STATEMENT AMONG FOUR RIGHT IN
EACH QUESTION
(III)
FIND WRONG STATEMENT AND MARK IT WITH X IN THE ANSWER
SHEET.
1.
Concerning plasma membrane
(a)
(b)
(c)
(d)
(e)
2.
About functions of plasma membrane
(a)
(b)
(c)
(d)
(e)
3.
Its thickness is 75 angstroms
The hydrophilic heads of the lipid bilayer consist of fatty acids
The integral proteins are transmembraneous
Na- K ATPase membrane proteins have Na- binding site on a P-face
The cell coat or glycocalyx is attached to the external surface of the
membrane
Exocytotic vesicles fuse with the plasma membrane and release their
content to the exterior (exocytosis)
Cell take up fluid by pinocytosis
Protein clathrin facilitates the process of formation of an endosome
Phagosome is the secondary lysosome
Diameter of the phagosome is more than 250nm
Regarding endoplasmic reticulum
(a)
(b)
(c)
(d)
(e)
Basophily of the cytoplasm in light microscope corresponds to the
ribosomes of RER in Electron microscope
Smooth endoplamic reticulum is well developed in the protein producing
cells
The polysomes are sites of active protein synthesis for the cell itself
Smooth endoplasmic reticulum detoxificates toxic substances
The membrane of cisternae of RER have a higher protein concentration
than the plasma membrane
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4.
Concerning Golgi apparatus
(a)
(b)
(c)
(d)
(e)
5.
About mitochondria
(a)
(b)
(c)
(d)
(e)
6.
The diameter of lysosomes varies from 0,5 to 0,8 micrometer
The lysosomes originate from the RER
The lysosomes contain hydrolytic enzymes
The peroxisomes contain enzyme catalase
The peroxisomes participate in gluconeogenesis and detoxification
Concerning cytoskeleton
(a)
(b)
(c)
(d)
(e)
8.
They are visible under the light microscope
Outer mitochondrial membrane is continuous
The oxysomes contain enzymes of Krebs cycle
The intermembranous space contains ATP
The mitochondria are capable to self-reproduction due to presence of
DNA in the matrix
Regarding lysosomes and peroxisomes
(a)
(b)
(c)
(d)
(e)
7.
Only external lamella of the “forming face” is of the fenestrated type
Secretory cells have extremely well developed Golgi apparatus
The Golgi complex is active in lysosome production
The Golgi apparatus repairs the cell membrane
During passage through the lamellae of Golgi complex, the proteins and
lipids are enriched with sugar residues
Microtubules form mitotic spindle
Microfilaments are actin filaments
Tonofilaments are found in the epithelial cells
The cilia have a central doublet of microtubules surrounded by nine
triplets of microtubules
Centrioles produce basal bodies of cilia
About nucleus
(a)
(b)
(c)
(d)
(e)
The ribosomes are attached to the external nuclear membrane
Pars granulosa of the nucleolus contains ribosomes
The nuclear pores are closed by the thin membrane
The perinucleolar chromatin is composed of RNA bound to histones
An euchromatin is more active than heterochromatin
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9.
Regarding mitosis
(a)
(b)
(c)
(d)
(e)
10.
Concerning cell death
(a)
(b)
(c)
(d)
(e)
11.
The chromatin pattern is not visible in the piknotic nucleus
The cytoplasm of dead cell is acidophilic and homogenuous
Karyorexis means lysis of the nuclear fragments
The mitochondria become swollen in the dying cell
The number of ribosomes is reduced in the dying cell
About epithelial tissue
(a)
(a)
(b)
(c)
(d)
12.
The chromosomes become visible during prophase
The mitotic spindle is formed during metaphase
The microtubules of the mitotic spindle are attached to the kinetochores
The splitting of the kinetochores occurs during anaphase
Movement of the chromatids during anaphase is due to pulling forces of
the mitotic spindle
Epithelia are nonvascular, receiving nutrients by diffusion from the blood
vessels of the connective tissue
Examples of simple epithelia: alveolar, mesothelium, endothelium,
columnar ciliated
Cornea is covered with stratified squamous nonkeratinized epithelium
The secretory cells of the mammary gland release their secretion by the
merocrine type
The myoepithelial cells are inserted between the base of the secretory cells
and the basement membrane
Regarding connective tissue
(a)
(b)
(c)
(d)
(e)
The plasma cells produce antibodies
Elastic fibers anastomose among each other
The bone collar is developed at the periphery of the epiphyseal cartilage
during fetal period
The osteoclasts are located within Hauship lacunae
The isogeneous groups of cartilage are surrounded by the capsules
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13.
About muscle tissue
(a)
(b)
(c)
(d)
(e)
14.
Concerning nervous tissue
(a)
(b)
(c)
(d)
(e)
15.
The Nissl substance occupies the perikaryon and dendrites of the nerve
cells
The myelin sheath of the nerve fibers in the CNS is formed by the
Sehwann cells
Vater-pacinian corpuscle is a pressure receptor
Meissner corpuscles are located within the papillary layer of the epidermis
Ependymal neuroglia cells line the central canal of the spinal cord,
ventricles of the brain stem, and hemyspheres
Regarding fertilization
(a)
(b)
(c)
(d)
(e)
16.
The sarcomere is part of the myofibril between two M-lines
The nuclei of the skeletal muscle fibers are located under the sarcolemma
The triads of the skeletal musculature are situated at the A-I junction
The smooth muscle tissue is innervated by the autonomic nervous system
The smooth muscle cells establish contacts among each other by the gap
junctions
It takes place within ampulla of the oviduct
It is possible during menstruation
It is possible in one day before or after ovulation
The zona reaction prevents polyspermy
Duplication of the DNA of both pronuclei occurs before their fusion
About cleavage and implantation
(a)
(b)
(c)
(d)
(e)
The morula, consisting of 16 blastomers, enters the uterine cavity on the
4th day after fertilization
The inner cell mass of morula is transformed into the embryoblast
The blastocyst is composed of more than 100 blastomers
The blastocyst is attached to the uterine mucosa on the 5th day after
fertilization
The embryonic pole of the trophoblast, embedded into the uterine mucosa,
is divided into the cytotrophoblast and syncytiotrophoblast
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17.
Concerning second week of development
(a)
(b)
(c)
(d)
(e)
18.
Regarding third week of development
(a)
(b)
(c)
(d)
(e)
19.
All three germ layers develop from the epiblast during gastrulation
The primitive streak is formed by the condensation of the cells of epiblast
The allantois is formed on the 20th day after fertilization
The tertiary chorionic villi have the mesenchymal core pierced by the
capillaries
Outer cytotrophoblast shell is developed at the end of the III week
Ectoderm gives origin to
(a)
(b)
(c)
(d)
(e)
20.
Heither’s membrane is formed by the hypoblast
The amnioblasts originate from the epiblast
The extraembryonic mesoderm is formed by the delamination of the
amnion cells
Implantation bleeding may occur on 13th day after fertilization
The definitive yolk sac is formed at the end of the 2nd week
Central and peripheral nervous system
Epidermis of the skin and its derivates
Thyroid, parathyroids glands, and thymus
Pituitary gland and epiphysis
Epithelial lining of the oral cavity
About derivatives of the endoderm
(a)
(b)
(c)
(d)
(e)
Epithelial lining of the GIT
Cornea, retina, lens of the eye
Respiratory system
Epithelial lining of the urinary passages
Prostate, bulbourethral glands, epithelial lining of the vagina
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SUBSECTION AII: MATCHING QUESTIONS
INSTRUCTIONS:
I)
II)
III)
THERE ARE FOUR (4) QUESTIONS IN THIS SECTION
ANSWER ALL THE FOUR (4) QUESTIONS
TO EACH NUMBERED ITEM (1-5) CHOOSE THE APPROPRIATE
LETTERED ONE (a-h) AND MARK X IN THE BOX PROVIDED
I.
Concerning cell
1.
2.
3.
4.
5.
II.
(a)
(b)
(c)
(d)
(e)
(f)
(g)
(h)
Glycogen synthesis
Synthesis of ribosomes
Synthesis of protein
Glycocalyx
Phagocytosis
Oxisomes
Chromatin
Hydrogen peroxide
(a)
(b)
(c)
(d)
(e)
(f)
(g)
(h)
Endocrine secretion
Microvilli
Production of mucus
Gap junction
Trachea
Holocrine type
Urinary bladder
Desmosome
(a)
(b)
(c)
(d)
(e)
(f)
(g)
(h)
Ribosomes
Sarcomere
Myosin filaments
Actin filaments
Histamine
Axon hillock
Incisure of Schmidt-lantermann
T-tubule
About epithelia
1.
2.
3.
4.
5.
III.
Plasma membrane
DNA
SER
Nucleolus
Peroxisomes
Columnar ciliated
pseudostratified epithelium
Macula adherens
Transitional epithelium
Brush border
Goblet cells
Concerning tissues
1.
2.
3.
4.
5.
Mast cells
Myelin sheath
Nissl substance
A- band
Z-line
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IV.
Regarding skin
1.
2.
3.
4.
5.
Stratum granulosum of epidermis
Langerhans cells
Reticular layer of dermis
Sweat glands
Meissner’s corpuscles
8
(a)
(b)
(c)
(d)
(e)
(f)
(g)
(h)
Merocrine secretion
Touch reception
Keratohyalin granules
Pressure receptors
Reticular fibers
Birbeck granules
Holocrine secretion
Collagen fibers (type I)
MSB 101
SECTION B: BIOCHEMISTRY (25 Minutes)
SUB-SECTION B I: MULTIPLE CHOICE QUESTIONS (MCQs) (25 minutes)
TYPE III
INSTRUCTIONS:(I)
EACH OF THE QUESTIONS IN THIS SUBSECTION CONSISTS OF A
STATEMENT/QUESTION
WHOSE
MOST
APPROPRIATE
COMPLETION/ANSWER IS PROVIDED AMONG THE FIVE OPTIONS
NUMBERED (a) - (e).
(II)
FOR EACH QUESTION SELECT THE MOST APPROPRIATE OPTION
AND INDICATE BY PRINTING AN X IN THE APPROPRIATE BOX IN
THE ANSWER SHEETS PROVIDED.
(III)
A CORRECT RESPONSE EARNS YOU ONE MARK.
1.
The genetic code is
(a)
(b)
(c)
(d)
(e)
2.
Degeneracy in the genetic code means
(a)
(b)
(c)
(d)
(e)
3.
A 4-letter alphabet
A collection f codons
A 3-letter code
A regulatory gene
A structural gene
That the genetic code comprises 64 codons
That the genetic code consists of 3-letter words
That the start and stop signals are called nonsense codons
The existence of multiple codons for one amino acid
Difference amino acids have different number of codons
Initiation of protein synthesis requires all of the following except
(a)
(b)
(c)
(d)
(e)
ATP
Initiation factors
mRNA
Initiation codon
GTP
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4.
Termination of protein synthesis occurs when
(a)
(b)
(c)
(d)
(e)
5.
Which of the following reactions is not included in protein processing?
(a)
(b)
(c)
(d)
(e)
6.
Are all involved in protein synthesis
Are as many as the number of amino acids required
Act as enzymic system catalyzing all amino acids
Are involved in sequential activation of amino acids
Require ATP for their activity
The following is not involved in modification of protein structure
(a)
(b)
(c)
(d)
(e)
8.
Cleavage by protease
Hydroxylation
Elongation
Glycosylation
Phosphorylation
Aminoacyl-tRNA synthetases
(a)
(b)
(c)
(d)
(e)
7.
Nonsense or terminating codon of mRNA appears
GTP combines with water
The protein is released from tRNA
40s or 60s ribosomes dissociates
Releasing factor appears
Deformylase enzyme
Signal peptidase enzyme
Addition of carbohydrate residue
Deletion of unusual amino acid derivatives
Addition of prosthetic group
Which of the following codons is the only methionine codon?
(a)
(b)
(c)
(d)
(e)
AUU
AUC
AUA
AUG
AGU
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9.
Which of the following amino acids has six codons?
(a)
(b)
(c)
(d)
(e)
10.
Which of the following factors would determine the acidic nature of nucleic
acids?
(a)
(b)
(c)
(d)
(e)
11.
Phosphodiester bonds
Electrostatic bonds
Covalent bonds
Hydrophobic bonds
Hydrogen bonds
DNA polymerase enzyme system includes all of the following except
(a)
(b)
(c)
(d)
(e)
13.
Phosphate unit
Adenine base
Ribose sugar
Pyrimidine base
Deoxyribose residue
Which of the following holds complimentary antiparallel strands in DNA
together?
(a)
(b)
(c)
(d)
(e)
12.
Tryptophan
Valine
Lysine
Glycine
Arginine
DNA repair activity
Nucleotide polymerization activity
Topoisomerase activity
5’3’ Exonuclease activity
3’5’ Exonuclease activity
Which of the following enzymes catalyzes the joining of nucleic acid strands
together?
(a)
(b)
(c)
(d)
(e)
Ligase
Primase
Restriction enzyme
Gyrase
Helicase
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14.
Which of the following triplet codons are made of termination codons?
(a)
(b)
(c)
(d)
(e)
15.
Which of the following forms the 5’ cap on mRNA?
(a)
(b)
(c)
(d)
(e)
16.
Adenosine
Guanosine
Cytosine
Uridine
Cytidine
The type of RNA with both structural and regulatory roles is
(a)
(b)
(c)
(d)
(e)
18.
7-Ethyladenosyl triphosphate
7-Ethylguanosyl triphosphate
7-Methylguanosyl triphosphate
7-methyladenosyl triphosphate
Polyadenylate residues
All of the following are nucleosides except
(a)
(b)
(c)
(d)
(e)
17.
UUU, UAG, UGA
UUG, UAG, UGC
UUC, UAG, UGA
UUA, UAC, UGA
UUA, UAG, UGA
snRNA
hnRNA
mRNA
tRNA
rRNA
The type of RNA with a sedimentation coefficient of 4s is
(a)
(b)
(c)
(d)
(e)
mRNA
tRNA
rRNA
snRNA
hnRNA
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19.
Which of the following modification is not involved in posttranscriptional
processing of RNA?
(a)
(b)
(c)
(d)
(e)
20.
Activated amino acids are carried to the ribosome for peptide-bond formation by
(a)
(b)
(c)
(d)
(e)
21.
hnRNA
snRNA
rRNA
tRNA
mRNA
Primary transcripts
(a)
(b)
(c)
(d)
(e)
23.
rRNA
mRNA
tRNA
hnRNA
snRNA
Which of the following nucleic acid is most rapidly degraded in mammalian
cells?
(a)
(b)
(c)
(d)
(e)
22.
Methylation of ribonucleotide in tRNA precursor
Methylation of ribose sugar
Attachment of amino acids
Hydrolysis of terminal nucleotide of RNA chain
Addition of phosphate units
Are larger than the final RNA molecule
Have no modification on the bases and sugars
Contain only A,G,C and U residues
Are by-products of RNA molecule
Are immediate products of RNA transcription
RNA transcription is facilitated by
(a)
(b)
(c)
(d)
(e)
DNA polymerase
RNA transcriptase
DNA-dependent RNA-polymerase
DNA-dependent RNA-polymerase
RNA-dependent RNA-polymerase
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24.
RNA polymerase requires all of the following except
(a)
(b)
(c)
(d)
(e)
25.
CTP
UTP
GTP
ATP
TPP
The direct carrier of genetic information from the nucleus to the cytoplasmic
ribosome is
(a)
(b)
(c)
(d)
(e)
rRNA
tRNA
mRNA
hnRNA
snRNA
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MSB 101
SECTION C: PHYSIOLOGY
MULTIPLE CHOICE QUESTIONS (MCQs) (66 minutes)
MCQ TYPE II: TRUE/FALSE
INSTRUCTIONS:
(I)
(II)
(III)
THIS SECTION CONSISTS OF TTHIRTY-THREE (33) QUESTIONS
ANSWER ALL THE THIRTY-THREE (33) QUESTIONS
EACH QUESTION CONSISTS OF A STEM STATEMENT FOLLOWED BY
FIVE (5) COMPLETIONS NUMBERED (a) TO (e).
(IV) A GIVEN COMPLETION, WHEN ADDED TO THE STEM STATEMENT
MAY PRODUCE A COMPLETE STATEMENT WHICH IS TRUE OR
FALSE.
(V)
INDICATE AGAINST THE APPROPRIATE NUMBER IN THE ANSWER
SHEET PROVIDED WHETHER THE COMPLETE STATEMENT IS TRUE
OR FALSE BY PRINTING AN X IN THE BOX IN THE COLUMN
HEADED T FOR “TRUE” OR F FOR “FALSE”.
(VI) IF YOU DO NOT KNOW WHETHER THE COMPLETE STATEMENT IS
TRUE OR FALSE, PRINT THE X IN THE COLUMN HEADED D FOR “DO
NOT KNOW”.
(VII) A CORRECT RESPONSE EARNS YOU PLUS (+) ONE MARK.
(VIII) AN INCORRECT RESPONSE EARNS YOU MINUS (-) ONE HALF OF A
MARK.
(IX) AN X IN THE ‘D’ COLUMN EARNS YOU ZERO MARK.
(X)
ANY UNASWERED OPTION WILL COUNT AS INCORRECT AND WILL
THEREFORE EARN YOU MINUS (-) ONE HALF (½) OF A MARK.
1.
Regarding nucleic acids
(a)
(b)
(c)
(d)
(e)
2.
DNA is composed of a pentose sugar, phosphate group and only pyrimidines
DNA is composed of only pyrimidines
They are composed of nitrogenous bases only
DNA molecule consists of two long chains of deoxyribonucleic coiled into a
double-helix shape
In DNA the base pairs hold the two chains
Deoxyribonucleic acids
(a)
(b)
(c)
(d)
(e)
Function sa the molecule of heredity
Only undergo semiconservative replicantion
Form only double stranded molecules during transcription
In one individual are identical and different from those of all other
individuals
In humans may have upto 100 million base pairs in a single molecule
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3.
Regarding ribonucleic acid molecules
(a)
(b)
(c)
(d)
(e)
4.
Regarding cell connections
(a)
(b)
(c)
(d)
(e)
5.
Fibrous, Bone, Cartilage and blood
Fibrous, Adipose, Cartilage and blood
Adipose, areolar, cartilage and blood
Hyalina, Fibrocartilage, blood and bone
Blood, Bone, reticular and fibrous
Regarding the bone tissue
(a)
(b)
(c)
(d)
(e)
7.
Immunoglobulins allow communication between cells
Desmosomes hold together the adjacent skin cells
Belt desmosomes appear to completely encircle the cells
Gap junctions are formed through adherence of membrane channels of
adjacent plasma membranes
Gap junctions occur in cardiac muscle cells so that a single impulse can
cause stimulation of many cells at the same time
The four main types of connective tissues are
(a)
(b)
(c)
(d)
(e)
6.
They poses ribose pentose sugar in addition to purines and phosphate groups
Some are temporary copies of segments of DNA code
Some are involved in the synthesis of proteins in the body
They are crucial in regulatory mechanisms and some act as enzymes
They are the main components of the human genome
It is regarded as the least specialized connective tissue which has osteocytes
embended in a calcified matrix
Inorganic component of the matrix account for 65% of the total tissue
It serves as a reservoir for minerals
It only supports the blood forming tissues under disease conditions
It provides the point of attachment for muscles and also gives support and
protection
The epithelial tissues
(a)
(b)
(c)
(d)
(e)
Are divided into glandular and membraneous epithelia
Lines only the serous cavities and the blood and lymphatic vessels
Also form the secretory units of the endocrine and exocrine glands
Serve the protection, sensory, secretion and absorption functions of the body
Have their cells in close proximity, with desmosomes and tight junctions
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8.
In cell communication
(a)
(b)
(c)
(d)
(e)
9.
The stages involved in cell signaling include
(a)
(b)
(c)
(d)
(e)
10.
(d)
(e)
The primary messenger molecules have no functional value
The primary messengers are mainly steroid in nature
Molecules that cross the cell membranes are regarded as the secondary
messengers
The reaction stops when the first signal receptor complex activates a
transducer protein
There is activation of amplifier proteins at the plasma membrane
The following are parts of neuron
(a)
(b)
(c)
(d)
12.
Reception
Retraction
Ejection
Transduction
Response
In the secondary messenger system
(a)
(b)
(c)
11.
The parracrine signaling involves local regulator chemical messengers that
target non specific receptors
Receptor specificity has no significance except in cases where the cells have
impermeable plasma membrane
The endocrine signaling does not require specialized cells
Specialized cells release molecules into the circulatory system which
transports them to distant target cells
Signaling can be more direct with cell-to-cell contact as in the case of gap
junctions but not desmosomes
Cell body
Dendrites
Axoplasm
Centromere
A neuron that is not conducting an impulse
(a)
(b)
(c)
(d)
(e)
Has no ability for registering an action potential
Has a membrane potential of about -70-mV
Maintains a net positive change outside the cell due to the presence of
potassium ions
Maintains a net negative change inside the cell due to the presence of large
negatively changed proteins
Maintains a potential difference through the activity of membrane channels
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13.
In the depolarization of nerve cells
(a)
(b)
(c)
(d)
(e)
14.
At a neuromuscular junction
(a)
(b)
(c)
(d)
(e)
15.
The arrival of an impulse at the nerve ending stimulates the release of
chemical transmitters which have receptors on the pre-synaptic membrane
only
The neurotransmitters are released from the muscle tissue
Binding of the neurotransmitters to their receptors increases the membrane
permeability to Na+
When the muscle membrane permeability is increased, the membrane
potential becomes more negative
An action potential is usually developed in the muscle cells without the
threshold potential criterion
Characteristics of muscles include
(a)
(b)
(c)
(d)
(e)
16.
Sodium ion channels are open
The large proteins move out of the neurons
There is no net movement of ions
Both sodium and potassium ion channels open in the opposite direction
The cell interior become more negative
Extensibility
Elasticity
Attachment to bones
Movement of skeleton
Striations
Regarding the nervous tissue
(a)
(b)
(c)
(d)
(e)
These have a role in the rapid regulation of body activities with limited
integration
The characteristics of the specialized cells include excitability and
conductivity
The specialized cells are localized in the brain and the spinal cord
Neuroglia are specialized in connecting supporting and coordinating the
activities of the neurons
The cells have limited capacity to repair themselves
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17.
Parts of a long bone include
(a)
(b)
(c)
(d)
(e)
18.
The following are types of bone cells
(a)
(b)
(c)
(d)
(e)
19.
Is also known as a diffuse connective tissue
Is also known as the myeloid tissue
Is the site for the process of hemopoiesis
Is found in the medullary cavities of long bones but not in the spongy bone
Occur in two forms namely the red marrow and the brown marrow
The functions of the skin includes
(a)
(b)
(c)
(d)
(e)
21.
Osteoblasts
Osteohepatocytes
Osteoclast
Osteomyeloblast
Osteocytes
The bone marrow
(a)
(b)
(c)
(d)
(e)
20.
Epiphyses
Diaphysis
Periosteum
Articular cartilage
Sarcomere
Barrier against infection and injury
Removal of waste products from the body
Providing protection against ultraviolet radiation from the sun
Production of vitamin D
Retention of body fluids
The muscle cells
(a)
(b)
(c)
(d)
(e)
Are called fibers because of their threadlike shape
Have sarcolemma which is the plasma membrane of the muscle fibers
Have sarcoplasmic reticulum whose function is to pump calcium in from the
sarcoplam into sacs for later release
Contain numerous mitochondria and nuclei in the fibers
Are non-contractile tissues of the body
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22.
Transverse tubules of muscles
(a)
(b)
(c)
(d)
(e)
23.
In cell division
(a)
(b)
(c)
(d)
(e)
24.
(e)
Transverse tubules are absent
The sarcoplasmic reticulum is loosely organized
Calcium ion from outside the cell binds to calmodulin instead of troponin
The arrangements of the thin and thick filaments produce organized
striations
The sarcomeres are more couspicous
Facilitated diffusion
(a)
(b)
(c)
(d)
(e)
26.
Mitosis has two phases unlike meiosis which has only one phase
The interphase stage is only found in mitosis but not meiosis
Prophase usually occur after the metaphase stage
Mitotic daughter cells are diploid (n)
The meiotic daughter cells are usually gamates
In the smooth muscles
(a)
(b)
(c)
(d)
25.
Extend across the sarcoplasm at right angles to the long axis of the muscle
fiber
Are formed by inward extension of the sarcoplasmic reticulum
Have membrane pumps that continually transport calcium ions inward from
the sarcoplasm
Allow electrical impulses traveling along the sarcolemma to move deeper
into the cell
Plays a major role in muscle cell replication
Is a type of passive transport
Moves molecules down the concentration gradient
Is made possible by specific molecules within the membrane
Requires no expenditure of energy
All of the above
Ion channels
(a)
(b)
(c)
(d)
(e)
Only open in response to a signal of some kind
Require input of energy in order to function
Have no limit to the rate at which they can transport ions
Can transport both negative and positive ions through
Allow passage of ions in both directions
20
MSB 101
27.
Homologous chromosomes are chromosomes that
(a)
(b)
(c)
(d)
(e)
28.
The sequence of stages in mitosis are
(a)
(b)
(c)
(d)
(e)
29.
Phosphate groups are hydrophobic
Fatty acids tails are ionized
Fatty acid tails are hydrophilic
Proteins are located only between the two layers
Phosphate heads are oriented toward the exterior of the cell or toward the
cytoplasm
The following cellular process is coupled with the hydrolysis of ATP
(a)
(b)
(c)
(d)
(e)
31.
Prophase, anaphase, prometaphase, metaphase, telophase
Prophase, telophase, anaphase, prometaphase, metaphase
Prophase, prometaphase, metaphase, anaphase, telophase
Telophase, prophase, prometaphase, metaphase, anaphase
Anaphase, telophase, prophase, prometaphase, metaphase
In a phospholipid bilayer the
(a)
(b)
(c)
(d)
(e)
30.
Are found only in identical twins
Are formed during mitosis
Split apart during meiosis I
Resemble one another in shape, size and function
Determine the sex of an organism
Facilitated diffusion
Active transport
Chemiosmosis
Osmosis
Na+ influx into a nerve cell
All of the following are involved in thermal regulation
(a)
(b)
(c)
(d)
(e)
Arteriovenous anastomoses
Accrine sweat glands
Papillary vascular plexus
Hair
Sebaceous
21
MSB 101
32.
The Golgi complexes
(a)
(b)
(c)
(d)
(e)
33.
Consist of stacks of saccules
In animal cells have a forming face and a maturing face
Modify molecules within its lumen of saccules
Bind lysosomes vesicles to enter its saccules
Contains enzymes
The most reliable feature distinguishing prokaryotic and eukaryotic cells is
(a)
(b)
(c)
(d)
(e)
The presence of a plasma membrane
The presence of a nucleus
The eukaryotic cell’s larger size
The presence of DNA
The presence of cell organalles
22
MSB 101
SECTION DI: IMMUNOLOGY (25 MINUTES)
INSTRUCTIONS:(I)
THIS PAPER IS MADE OF TWO (2) SUBSECTIONS: I AND II.
SUBSECTION I CONSISTS OF FIFTEEN (15) MULTIPLE CHOICE
QUESTIONS (MCQs) TO BE ANSWERED IN FIFTEEN (15) MINUTES.
SUBSECTION II CONSISTS OF ONE (1) SHORT ANSWER QUESTION
(SAQ) TO BE ANSWERED IN TEN (10) MINUTES.
(II)
FOR
THE
MCQs,
EACH
QUESTION
CONSISTS
OF
STATEMENT/STEM WHOSE MOST CORRECT RESPONSE
PROVIDED AMONG THE FIVE OPTIONS NUMBERED A TO E.
(III)
FOR EACH MCQ, SELECT ONLY ONE MOST APPROPRIATE OPTION
AND INDICATE BY CIRCLING IT.
A
IS
EXAMPLE:C1 - esterase inhibitor deficiency is associated with
(a)
Reccurent Neisserial infections and SLE
(b)
Hereditary neurotic angiodema
(c)
Selective Ig G4 deficiency
(d)
X - linked agammaglobulinaemia
(e)
CD 8+ T cell dysfunctions
The appropriate response is (b)
(iv)
A CORRECT RESPONSE IN THE MCQs EARNS YOU PLUS ONE (+1)
MARK. AN INCORRECT RESPONSE EARNS YOU MINUS HALF (-½ ) A
MARK. NO PENALTY FOR UNATTEMPTED MCQ.
(v)
ATTEMPT ALL QUESTIONS IN THE TWO SUBSECTIONS.
SUB-SECTION DI: MULTIPLE CHOICE QUESTIONS (MCQs) (15 minutes)
1.
The locational map of Ig locus on chromosome 14 includes the following regions
(a)
(b)
(c)
(d)
(e)
V, D, J & C regions
MHC I, II & III regions
The region 6p21.1 to 6p21.3
Transporter genes (TAP)
2- microglobulin
23
MSB 101
2.
The most polymorphic MHC region is
(a)
(b)
(c)
(d)
(e)
3.
MHC genes are specifically located on the
(a)
(b)
(c)
(d)
(e)
4.
Complement proteins coded for by class II genes
HLA-DP, DM, DO, DQ and DR code for class II molecules
HLA-B, C, E, A, G and F code for class II molecules
Tumour necrosis factor (TNF) coded for by class I genes
Lymphotoxin and heatshock proteins coded for by class II genes
T cell receptor is co-expressed with
(a)
(b)
(c)
(d)
(e)
6.
Long arm of chromosome 6
Short arm of chromosome 14
Shorter arm of chromosome 6
Long arm of chromosome 2
Short arm of chromosome 16
On chromosome 6, MHC molecules are coded as follows
(a)
(b)
(c)
(d)
(e)
5.
HLA-C
HLA-B
HLA-A
HLA-DR
HLA-DQ
CD19
CD20
CD3
CD5
CD6
Class III MHC regions does not code for
(a)
(b)
(c)
(d)
(e)
Tumour necrosis factor (TNF)
Lymphotoxin (LT)
Factor B
21-hydroxylaxe enzyme
TAP 1 & TAP 2
24
MSB 101
7.
Members of immunoglobulin superfamily molecules EXCLUDE
(a)
(b)
(c)
(d)
(e)
8.
The following cells present antigen EXCEPT
(a)
(b)
(c)
(d)
(e)
9.
CD 3….L FA – 3
LFA-1….ICAM
CD28….B7 (CD80/CD86)
CD2…..LFA – 3
CD45R…..CD22
HLA alleles in strong linkage disequilibrium are
(a)
(b)
(c)
(d)
(e)
11.
Platelets
Follicular dendritic cells
Macrophages
Langerhan cells
Dendritic cells
T cell-antigen presenting cell (APC) interaction is NOT mediated by the
following adhesion molecules
(a)
(b)
(c)
(d)
(e)
10.
BCR and TCR
CDI thymocytes
-2 microglobulin
MHC molecules (I + II)
CD2 and C-reactive protein
A1 and B9
A11 and B8
A29 and B5
A1 and B5
A1 and B8
Class II molecules are located on
(a)
(b)
(c)
(d)
(e)
Mesenchymal tissue
Epithelial cells
All nucleated cells
All T ells
B cells, dendritic & thymic epithelial cells
25
MSB 101
12.
Antigen presenting cells (APC) selectively express
(a)
(b)
(c)
(d)
(e)
13.
Characterization of HLA alleles is NOT
(a)
(b)
(c)
(d)
(e)
14.
Essential to ensure successful organ/tissue transplantation
Important in paternity identity
Valuable in resolving blood group typing complications
Well established in dental plagues
Considered in susceptibility to autoimmune disease
Cytotonic T lymphoctytes are
(a)
(b)
(c)
(d)
(e)
15.
HLA – class II gene products
HLA – class I gene products
HLA – class III proteins
HLA – A, B and DR molecules
HLA – DP, DR and F molecules
MHC class I restricted
MHC class III restricted
MHC class II restricted
Express surface IgM & IgD
Similar to natural killer (NK) cells in MHC restriction
Epidermis of the skin is NOT equipped with the following cell types
(a)
(b)
(c)
(d)
(e)
Kuppfer cells
Langerhans cells
Keratinocytes
Epithelial cells
Dendritic cells
26
MSB 101
SUBSECTION D11: SHORT ANSWER QUESTION (10 minutes)
INSTRUCTIONS:
I)
II)
SAQ 1.
THERE IS ONE (1) SHORT ANSWER QUESTION IN THIS
SUBSECTION
ANSWER THE QUESTION
Explain with the aid of annotated diagram describe the structure of MHC
class I molecule.
(10 marks)
27