Selected MCQs in General Biology
1- Synthesis and breakdown of polymers is made by
a- dehydration and condensation
b- dehydration and hydration
c- addition of water molecule only d- removal of water molecule only
2-One of the following macromolecules is not a polymer
a- Cellulose b- Starch c- Nucleic acid d- Sex hormones
3- β- glycosidic linkages is present in the polymers of
a- Amylose b- Amylopectin c- Cellulose d- Glycogen
4- All of the following is true about hydrogenated vegetable oils, EXCEPT ONE
a- They were unsaturated
b- They turned to be saturated
c- Are liquid at room temperatures d- Are solid at room temperatures
5- Phospholipids are amphipatic because of their
a- hydrophobic head and hydrophilic tails b- hydrophilic head and hydrophilic tails
c- hydrophobic tails and hydrophilic heads d- hydrophobic tails and hydrophobic tails
6- Steroids are synthesized from cholesterol by
a- changes in the four fused carbon rings b- different substitutions on the side chains
c- deletion of one ring
d- addition of one more ring
7- Triacylglycerol is a lipid molecule constructed from 3 fatty acids attached to one
molecule of glycerol by
a- α, 1-4 glycosidic linkage b- peptide bond c- ester linkage d- β, 1-4 glycosidic
likage
8- A phospholipids molecule is similar to a fat molecule but it has only------fatty acids
a- three b- one c- two d- four
9- Tertiary protein is
a- single polypeptide with β-helix formation
b- single polypeptide with α-pleated sheets formations
c- single polypeptide with β-helix formation and α-pleated sheets formations
d- with β-helix formation and α-pleated sheets formations on two polypeptides
10- One of the following chemical bonds is not involved in the folding of protein
a- hydrogen bonds b- hydrophobic bonds c- ionic bonds d- peptide bonds
11- Proteins of hair, horns, feathers and other skin appendages is
a- storage protein b- enzymatic protein c- hormonal protein d- structural protein
12- The first step in the cycle of an enzyme is
a- substrate binds to enzyme b- substrate converted
c- products released
d- enzyme become free
13- All polypeptides have the same “backbone” structure but they differ in their “R”
groups only
a- true
b- false
14- The polynucleotide is characterized by the followings EXCEPT ONE
a- usually present in double-strands
b- each strand has 3’ end and 5’ end
c- strands are in a parallel arrangement
d- Nitrogenous bases are in a complementary arrangement between the two strands
15- For sequence of 5’-AGGTCCG-3’, there is a complementary sequence
a- 5’-ACCGTAAG-3’ b- 3’-TCCAGGC-5’
c- 3’-TGGACCX-5’
d- 5’-TCCAGGC-3’
16- Electron microscopy provide high magnification and resolution because it uses
a- a beam of UV
b- the blue light spectrum
c- a beam of electrons d- a beam of protons
17- Prokaryotic cells, they have DNA is present in
a- nucleus b- nucleiod c- nucleolus d- mitochondria
18- All cells are bound by plasma membrane, but not all cells have cell wall
a- true b- false
19- The protein associated with protein folding and discovered in the bacteria E. coli
is called
a- hemoglobin b- collagen c- chaperonin d- lysosome
20- Nucleic acids are polymers of the following monomers
a- nucleosides b- nucleotides c- pentose sugar d- hexose-phosphate sugar
21- A male (man) with a defected dynin is likely to become sterile because his sperms
a- are not formed b- not active c- can not swim d- have no flagellum
22- Nuclear membranes are, EXCEPT ONE
a- part of the endoplasmic membranes system
b- continuous with the endoplasmic membranes
c- outer and inner membranes are connected by pore complexes
d- outer membrane contains no ribosomes
23- Nuclear lamina is made of
a- microtubules
b- microfilaments
c- intermediate filaments d- microtubules and microfilaments
24- Ribosomes are, EXCEPT ONE
a- made of two protein subunits b- some are present on the surface of the rough ER
c- some are present free in the cytosole d- they are bound by single membrane
25- The enzymes of the smooth ER are important to synthesis of; EXCEPT ONE
a- oils b- phospholipids c- steroids
d- carbohydrates
26- Cells in the testes and ovaries are rich in
a- smooth ER
b- rough ER c- lysosmes
d- peroxiosomes
27- One of the following is a mismatch
a- bound ribiosomes—secretory proteins
b- bound reibososmes—nuclear outer membrane
c- free ribosomes—cytoplasmic enzymes
d- free ribosomes—secretory proteins
28- Enzymes of the lysosomes function in the following EXCEPT ONE
a- phagocytosis
b- Autopahgy
c- lipid digestion d- work better in basic(alkaline) medium
29- The free ribosomes of the mitochondria are present in its
a- Inter-membrane space b- Mitochondrial matrix
c- on the outer-membrane d- on the cristae of the inner membrane
30- The grana are made of
a- stacked thylakoids
b- Stroma
c- inner chloroplast membranes d- outer chloroplast membrane
31- Peroxisomes are characterized by the following EXCEPT ONE
a- bound by single membrane b- Produce H2O2
c- Converts H2O2 to water
d- bud from the endo-membrane system
32- Centrosome is characterized by
a- two centrioles each one is made of 9 triplets of microtubules
b- Two ceneriles each one is made of (9+2) pattern of microtubules
c- one centriole made of 9 triplets of microtubules
d- not identical with the basal body
33- Flagella and cilia are; EXCEP ONE
a- bound by the plasma membrane
b- anchored to the basal body
c- have a core of 9 duplets outer plus 2 central microtubules
d- Both are anchored to the plasma membrane
34- Motor protein is involved in one of the following
a- Movement of the flagella in prokaryote cell
b- Pseudopodia formation
c- movement of cilia and flagella in eukaryote cells
d- Cytoplasmic streaming inside plant cells
35- Bilayer phospholipids membranes are
a- fluid when their lipid contains unsaturated fatty acids
b- viscous when their lipid contains unsaturated fatty acids
c- fluid when their lipid contains saturated fatty acids
d- fluid when they contain more cholesterol
36- A hybrid cell made by fusion of mouse and man RBCs indicated
a- proteins of the membrane move side way
b- proteins of the membrane undergo “flip-flap”
c- proteins of the membrane do not move at all
d- phospholipid molecules do “flip-flap”
37- lycoprotein, glycolipid and fibers are components of the
a- ECM or outer surface of the plasma membrane b- Cytoplasmic side of the
membrane
c- both sides of the plasma membrane
d- the inside of the plasma membrane it
self
38- A bacterial transport protein, bacterirhodopsin is characterized by EXCEPT ONE
a- integral protein with 7 transmembrane helices
b- with N-terminus outside cell and C-terminus inside cytoplasm
c- α helix (7 helices) hydrophobic and non-helical hydrophilic
d- It is a peripheral protein attached to microfilaments cytoskeletone
39- Biological membranes are permeable and selective because; EXCEPT ONE
a- made of bilayer of phospholipids and proteins
b- being hydrophobic inside (in their center) and hydrophilic on both surfaces
c- they have channels and carriers
d- some of their transport proteins act only when become phosphorylated
40- Osmosis is characterized by
a- diffusion of water molecules across non - permeable membrane
b- it is an active process requiring ATP
c - water diffusion from hypotonic to hypertonic solution across semipermeable
membrane
d- water diffusion from hypertonic to hypotonic solution across semipermeable
membrane
1-The most prevalent and effective catabolic pathway in living cells is,
a- Fermentation
b- Cellular respiration
c- Photosynthesis d- all of the above is correct
2-Loss of electrons from one substance is called
a-Oxidation
b-Reduction
c-Dehydrogenation d-Phosphorylation
3-Cell division results in
a- Genetically identical daughter cells
b- Genetically not identical daughter cells
c- Daughter cells with different genomes d- All of the above is correct
4- Offspring acquire genes from parents by inheriting
a- Chromosomes b- Cytoplasm c- Neucleotides
d- RNA
5- Addition of electrons to another substance is called
a- Oxidation b- Reduction c- Dehydrogenation
d- Phosphorylation
+
6- NAD becomes NADH+H in conjunction with the enzyme called,
a- Dehydrogenase b- Hydrogenase c- Glucosidase d- Kinase
7- Respiration uses ------- mechanism in a "stepwise" manner of energy release
a- Glycolysis b- Citric acid cycle c- Electron transport chain d- all of the above
8- Living cells generate ATP by
a- Oxidative phosphorylation
b- Substrate level phosphorylation
c- Both of the above
d- none of the above
9- Energy investment phase in glycolysis for one glucose molecule is ----ATP
molecules and energy payoff is ----ATP and ---- NADH molecules
a- 2, 4, and 2 b- 4, 2, and 2
c- 2, 2, and 4
d- 2, 2, and 2
10- One of the following happens in the cytosol
a- Glycolysis b- Citric acid cycle c- Electron Transport Chain d- release of CO2
11- Citric acid cycle produces ----- NADH molecules and ------ATP molecules on
substrate level and -------FADH2 molecules from each one pyruvate molecule
a- 3, 1, and 1 b- 6, 2, and 2 c- 1, 1, and 3 d- 2, 2, and 6
12- The first CO2 produced via cellular respiration comes as
a- the carboxyl group (-COO-) of pyruvate is removed b- acetate react with CoA
c- Acetyle CoA is formed
d- Acetyle CcA breaks down
13- Pyruvate is transported from cytosol into mitochondria via;
a- Active transport b- Passive transport
c- Simple diffusion d- Facilitated passive transport
14- ATP- Synthase ( a Molecular Mill) is a membrane protein complex with it's knob
facing mitochondrial matrix is powered by
a- the flow of hydrogen ions b- ATP
c- ADP d- Pi
15- If the outer membrane of a mitochondrion get rupture (cut or broken) the
following process stop functioning
a- Chemiosmosis b- Glycolysis
c- ETC d- Citric acid cycle
16- Oxidative phosphorylation include
a- ETC and Chemiosmosis
b- ETC only
c- Chemiosmosis only
d- Glycolysis and fermentation
17- The 2NADH produced via glycolysis and upon electron shuttle span membrane
into the mitochondria may go in at energy level of 2FADH then respiration produce--ATP from each one glucose molecule
a- 36 b- 38 c- 30
d- 18
18- Cytokinesis is the division of
a- Cytoplasm b- Nucleus c- Nucleolus d- Cytosol
19- One of the following is not part of the interphase in cell cycle
a- Metaphase b- Gap 1 c- Gap 2 d- S-phase
20- DNA synthesis happens during the ----in the cell cycle
a- S-phase b- G2 c- G1 d- Prometaphase
21- Kinetochore microtubules are established at
a- Prophase b- Prometaphase c- Metaphase d- Anaphase
22- One of the following is the longest phase in mitosis
a- Prophase b- Prometaphase c- Metaphase d- Anaphase
23- The two sister chromatids of each pair suddenly part becoming chromosomes at
the shortest stage of mitosis called
a- Prometaphase b- Metaphase c- Anaphase d- Telophase
24- Kinitochore microtubules actually pull the new chromosomes apart from each
other proved by
a- presence of motor protein at the kinetochore attachment
b- Accumulation of tubulin subunits at this stage
c- Kinetochore microtubules section between marker and chromosomes become
shorter
d- all of the above is correct
25- Cytokinesis in animal cells is accomplished by
a- Cleavage furrow made by contractile ring of microfilaments
b- Cleavage ring made by microtubules
c- Binary fission
d- Cell plate formation
26- An M phase cell fused with another G1 phase cell, and then the chromosomes of
the latter one become made of
a- two sister chromatids b- no chromatids formed
c- long not condensed
d- contains the same amount of DNA as the M cell
27- The following Checkpoint of mammalian cells is called "restriction point"
a- G1 b- G2 c- M d- G and G2
28- Dividing cells will pass G2 checkpoint only when the following molecules reach
high concentration
a- Cdk b- MPF c- Cyclin only d- Kinase
29- One of the following is not an external physical factor on cell division
a- PDGF
b- Density – dependant inhibition
c- Anchoring dependant d- limited number of cells per given surface area.
30- Metastasis is the spread of
a- Cancer cells
b- Benign tumor cells
c- Malignant tumor cells d- a and c is correct
31- The following kind of reproduction does not involve meiosis
a- Asexual reproduction and clone formation b- Alternation of generations
c- Sexual life cycle in animals
d- Sexual life cycle in some fungi
32- A karyotype of a normal somatic human cell at metaphase shows
a- 22 pairs of autosomes plus X and Y chromosomes b- 46 sister chromatids
c- 23 chromosomes
d- 22 + 1 chromosomes
33- As a result of crossing over during meiosis the chromosomes will be
a- Recombinant and parental chromosomes b- Recombinant chromosomes only
c- Paternal Chromosomes only
d- Maternal Chromosomes only
34- In plants and some algae the sexual life cycle involves an "alternation of
generation" where;
a- haploid spores divide by mitosis producing gametophytes
b- Diploid zygote divides by mitosis producing sporophytes
c- Gametes are produced by mitosis and haploid spores are produced by meiosis
d- all of the above is correct
35- In the sexual life cycle of most fungi and some protists the only diploid stage is
a- The zygote b- the multicellular organism c- Gametes d- Spores
36- Meiosis reduces the number of chromosome sets from;
a- diploid to haploid b- n to 1/2 n c- 2n to n d- a and c is correct
37- The diploid number of chromosomes is reduces in half via the following stage of
meiosis
a- Meiosis I b- Meiosis II c- Meiosis I and II d- Interphase
38- Chiasmata and crossing over occurs during the following phase of meiosis
a- Prophase I b- Prophase II c- Metaphase I d- Metaphase II
39- The centromere of each chromosome divide during the following phase of
meiosis
a- Anaphase I b- Anaphase II c- Metaphase I d- Metaphase II
40- Crossing over and exchange of chromatin segments happen between--------of the
tetrads bind together by synaptonemal protein
a- Non-sister chromatids of homolog chromosomes
b- Sister chromatids of homolog chromosomes
c- non-sister chromatids of non-homolog chromosomes
d- Sister chromatids of non-homolog chromosomes