Download Model Questions 1

‫المملكة العربية السعودية‬
‫جامعة امللك سعود‬
‫كلية العلوم‬
‫قسم الكيمياء احليوية‬
-Choose the correct answer:
1- What kind of connective tissue acts as a sponge
a- Areolar
b- Adipose
c- Reticular
d- Vascular
2- Which of the following would you expect to find in or on cells whose main function is
absorption:
a- Microvilli
b- Cilia
c- Gap junctions
d- Secretory vesicles
3- In which of the following tissue types might find macrophages
a- epithelia tissue
b- connective tissue
c- muscular tissue
4- What type of connective tissue prevents muscles from pulling away from bones during
contraction?
a- Dense connective
b- Areolar
c- Elastic connective
d- Hyaline cartilage
5- Which of the following terms does not describe connective tissue?
a- connecting
b- transport fluids
c- producing heat
d- storing energy
6- What is the organ that has abundant elastin in its structure?
a- Muscle
b- Lung
c- bone
d- nose
7- To what kind of tissues belong the skeletal system
a- Muscular
b- connective
d- epithelial
d- Nervous
8- Which of the following terms describes connective tissue?
a- bone
b- extracellular matrix
c- lymphocytes
d- simple columnar
9- Fibroblasts, Macrophages, adipocytes, melanocytes, mast cells exist in:
a- connective tissue proper
b- dense connective tissue
c- epithelia tissue
10- Which of the following proteins contain 30% glycine, and 30% Pro + HyPro
a- Collagen
b- Keratin
c- Elastin
d- Actin
11- Which of the following proteins contain larger amount of cystein
a- Collagen
b- -Keratin
c- Elastin
d- fibroin
12- Which of the following proteins contain the repeat [Gly-Ala-Gly-Ala-Gly-Ser-Gly-Ala-AlaGly-(Ser-Gly-Ala-Gly-Ala-Gly)8]
a- Collagen
b- Keratin
c- Elastin
d- fibroin
Prepared by Dr. Farid Sh. Ataya
http://faculty.ksu.edu.sa/75112
‫المملكة العربية السعودية‬
‫جامعة امللك سعود‬
‫كلية العلوم‬
‫قسم الكيمياء احليوية‬
13- Which of the following proteins contain 30% glycine, and 30% Ala+Val but no HyPro
a- Collagen
b- Keratin
c- Elastin
d- fibroin
14- Which of the following proteins has unique triple helix structure
a- Collagen
b- Keratin
c- Elastin
d- fibroin
15- Connective tissue proper does not contain
16- a- collagen fibers
b- cartilage
17- Bone contains
a- osteocytes
b- adipocytes
c- reticular fibers
c- collagen fibers
d- elastic fibers
d- epithelial cell
18- Vitamin C (ascorbic acid) is important for formation of:
a- praline
b- hydroxyproline only
c- hydroxylysine only
19- Collagen exists in
a- extracellular matrix
b- cytoplasm
20- -Keratin is predominant in
a- hair
b- silk
21- Dentin
a- Covers root of tooth
c- makes up anatomic crown
22- Spongy bones exist in
a- External ear
b- c- fluid connective tissue
d- (b and c)
c- dentin
d- pulp
c cartilage
d- lymph
b- made up of blood vessels and nerves
d- makes up bulk of tooth
b- Skull
d- non of the above
23- Simple cuboidal epithelia
a- found in ovary, renal medulla
c- found in blood vessels and kidney tubules
b- exchange simple gases
d- has disc shaped nucleus
24- Simple columnar epithelia
a- is composed of several lauers
c- has a nucleus near basement membrane
b- found in mouth and eosophagus
d- protects against abrasion in moist area
25- An epithelium “built” to withstand friction is:
a- Simple squamous
b- Stratified squamous
c- simple columnar
d- Psuedostratified
26- Which of the following may act as glue in the epithelial tissue
a- actin
b- occluding
c- fibrin
d- connexon
27- The muscle that might contain more gap junctions is
a- Cardiac muscle
b- Bone
c- Skeletal muscles
Prepared by Dr. Farid Sh. Ataya
d- Smooth muscles
http://faculty.ksu.edu.sa/75112
‫المملكة العربية السعودية‬
‫جامعة امللك سعود‬
‫كلية العلوم‬
‫قسم الكيمياء احليوية‬
28- A mononucleated branched cell with connexones is found in
a- skeletal muscle
b- fibrous tissue
c- cardiac muscle
d- smooth muscle
29- A long-multinucleated- striated cell is found in
a- skeletal muscle
b- fibrous tissue
c- cardiac muscle
d- smooth muscle
30- A spindle shaped-mononucleted without striation cell is found in
a- skeletal muscle
b- fibrous tissue
c- cardiac muscle
d- smooth muscle
31- Which of the following terms does not describe cardiac muscles?
a- Multinucleted
b- Intercalated discs c- Involuntary
d- Branched
32- Which of the following terms does not describe muscle tissue?
a- covering
b- producing heat
c- maintaining posture
d- movement
33- Myosin II
a- has a long neck region
b- has only one heavy chain
c- Short coiled-coil region flowed by a globular domain at the end of its tail
d- has two heavy chains, each with a globular motor domain
34- Cardiac muscles are
a- short, fat and branched
c- has no striation
b- found in stomach and intestine
d- is voluntary
- Respond to the following statement by writing T (True) or F (False):
1- Bone growth can be regulated by sex hormones
(
)
2- Calcitonin increases renal excretion of calcium and phosphate
(
)
(
)
4- Enamel is incapable of remodeling and repair
(
)
5- Long bones found in ankle and the wrist
(
)
6- Vitamin K is important for protein synthesis in bone
(
)
7- Parathyroid hormone increases serum calcium level
(
)
8- Parathyroid hormone decreases renal excretion of phosphate
(
)
3- The pulp of the tooth contains connective tissue,
which aids interchange between pulp and dentin
9- Cortitical bone has densely patched calcified intercellular matrix that
Prepared by Dr. Farid Sh. Ataya
http://faculty.ksu.edu.sa/75112
‫المملكة العربية السعودية‬
‫جامعة امللك سعود‬
‫كلية العلوم‬
‫قسم الكيمياء احليوية‬
makes it more rigid than cancellous bone
10- Growth hormone increases intestinal absorption of calcium
(
)
(
)
(
)
11- The body stores both retinol and beta-carotene in the adipose tissue,
drawing on this store whenever more vitamin A is needed.
12- Fluoroapatite is converted in acid medium to soluble hydroxyapatite
(
)
13- Hydroxyapatite is converted in acid medium to solid hydroxyapatite
(
)
(
)
14- Hydroxyapatite is converted in presence of fluoride medium to
soluble hydroxyapatite
- Answer the following questions:
1- What are the general structural characteristics of connective tissues?
- All connective tissues share three basic components
a. Specialized cells
b. Extracellular protein fibers
c. Fluid known as a ground substance
2- What are the functions of connective tissues? And how are their functions reflected in their
structure?
- Connective tissue has different functions like:
a. Connect tissues
b. Establish a structural framework
c. Transport fluids and dissolved materials
d. Protect delicate organs
e. Store energy
f. Defend the body from microorganisms
3- Name the most common fibers existing in connective tissues?
a.
Collagen
b.
Elastin
c.
Keratin
d.
Fibroin
4- Compare between connective tissue proper, fluid connective tissue and supporting connective
tissue (give example of each).
- connective tissue proper:
a. Contains varied cell populations
Prepared by Dr. Farid Sh. Ataya
http://faculty.ksu.edu.sa/75112
‫المملكة العربية السعودية‬
‫جامعة امللك سعود‬
‫كلية العلوم‬
‫قسم الكيمياء احليوية‬
-
-
b. Contains various fiber types (loose or dense)
c. A syrupy ground substance
fluid connective tissue
a. Contains a distinctive cell population
b. Watery ground substance with dissolved proteins
c. Two types, Blood and Lymph
supporting connective tissue
a. Less diverse cell population
b. Dense ground substance
c. Closely packed fibers
d. Two types, Cartilage and Bone
5- Name six of the cell population of the connective tissue proper
Fibroblast
Mesenchymal cells
Macrophages
Microphages
Adipocytes
Melanocytes
Lymphocytes
Mast cells
6- Name the different types of cartilage and give examples, location and the function of each.
There are three types of cartilages:
1- hyaline
2- elastic
3- fibrocartilage
7- What are the main features of the secondary structure of collagen?
Collagen is formed from tropocollagen subunits. The triple helix in tropocollagen is highly extended
and strong.
Features:
a. Collagen triple helix is formed from three separate polypeptide chains arranged as a lefthanded helix (note that a-helix is right-handed).
b. 3.3 amino acid residues per turn
c. Each chain forms hydrogen bonds with the other two to make it more strong
 The unusual amino acid composition of collagen is not favorable for alpha helices OR beta sheets
 But it is ideally suited for the collagen triple helix: three intertwined helical strands
Prepared by Dr. Farid Sh. Ataya
http://faculty.ksu.edu.sa/75112
‫المملكة العربية السعودية‬
‫جامعة امللك سعود‬
‫كلية العلوم‬
‫قسم الكيمياء احليوية‬


It is much more extended than alpha helix, with a rise per residue of 2.9 A°
There are long stretches of Gly-Pro-Pro/HyP
8- State the main steps in the biosynthesis of tropocollagen
In the cytoplasm ,Syntheis of peptide chains in ribosomes and their transfer along the Rough
Endoplasmic Reticulum (RER).
Inside RER ,Peptide chains are sent into the lumen of the RER ,
 Cleavage of signal peptides.
 Hydroxylation of Y- prolyl and some Y-lysyl .
 Glycosylation of specific hydroxy lysyl residues.
 Formation of intra and inter chain disulfide bonds.
 Formation of the helical structure starting from the C-terminal.
Inside Golgi apparatus, procollagen is shipped to the Golgi apparatus ,where it is packaging and
secretion of the procolagen.
Outside the cell
 Cleavage of pro sequence .
 Formation of fibrils followed by fibers.
 Assembly of collagen fibers in quarter-staggered alignment.
 Collagen is attached to cell membranes via several types of protein ,including fibronectin and
integrin .
9- Compare between collagen and elastin.
Collagen
Elastin
Genetic types
Shape of fiber
Amino acid structure
Presence of
hydroxylysine
glycosylation
Types of crosslinkes
Presence of extention
during synthesis
10- Explain the role of PTH in bone formation.
a. Increases intestinal absorption of calcium
b. Increases intestinal absorption of Phosphate
c. Decreases renal excretion of calcium
d. Increases renal excretion of phosphate
e. Increases bone resorption
f. Decreases bone formation
g. Promptly increases serum calcium levels
h. Prevents increase in serum phosphate levels
11- Explain the role of calcitonin in bone formation.
a. Increases renal excretion of calcium
b. Increases renal excretion of phosphate
Prepared by Dr. Farid Sh. Ataya
http://faculty.ksu.edu.sa/75112
‫المملكة العربية السعودية‬
‫جامعة امللك سعود‬
‫كلية العلوم‬
‫قسم الكيمياء احليوية‬
c. Decreases bone resorption
d. Decreases serum calcium levels with pharmacologic doses
e. Decreases serum phosphate levels with pharmacologic doses
12- What are the main functions of the epithelial tissue (give examples)?
a. Protection (Against wear and tear, Keratin and mucous prevent drying)
b. Absorption & filtration (Microvilli in kidney and intestine)
c. Surface transport (Via cilia on cell surface)
d. Secretion (all glands are epithelia) (Hormones. Digestive enzymes, mucus)
e. Sensory reception
13- Name four criteria to classify epithelial tissues.
a- Shape
b- Number of layers
c- Specialization
d- Covering and lining vs. glandular
14- What are the main functions of the basement membrane in the epithelial tissue?
a. Structural support via cell-matrix adhesions
b. Allow nutrients and waste to diffuse
c. Filter for macromolecules (Kidney)
d. Zone for differentiation and polarization of cells.
e. Plays a role in regeneration by acting as a “highway” for cell migration.
15- What are the three layers forming the basement membrane in the epithelial tissue?
a) Top two from epithelia, also called basal lamina
• Lamina rara (Lucida)
• Lamina densa
b) Lowest from connective tissue.
• Reticular lamina (Lamina fibroreticularis)
16- Compare between the different intercellular junctions in epithelial tissue?
Junction
Fiber & glue
Function
ZO
occludin
Sealing
ZA
Actin, Cadherin
Adhering
MA
Desmosome
Keratin/
Actin, Integrin
Adhering laterally
Gap
Connexon
Communication
Hemidesmosome
Keratin, Integrin
Adhering from the base
Prepared by Dr. Farid Sh. Ataya
http://faculty.ksu.edu.sa/75112
‫المملكة العربية السعودية‬
‫جامعة امللك سعود‬
‫كلية العلوم‬
‫قسم الكيمياء احليوية‬
17- How do epithelia cells join together? Name the different types of intercellular junctions in
epithelial tissue?
Types of intercellular junctions:
a. Occluding junctions or Tight junction (form seals and are impermeable)
b. Adhering junctions or desmosome junction (glue cells together and are associated with
specific cytoskeletal elements)
c. Communicating junctions or Gap junction
18- What are the functions of muscle tissue?
19- Name the types of muscle tissue and tell where each would be found in the body and the general
difference in structure, tiredness and innervations?
Prepared by Dr. Farid Sh. Ataya
http://faculty.ksu.edu.sa/75112