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Biology Multiple Choice Questions and Answers for Different Competitive Exams

Practice Test on Algae - Diversity in Living World

Algae are pigmented thallophytes. They prepare their own food materials with the help of chlorophyll and sunlight. So they are said to be autrotrophs. Besides chlorophyll there are other colored pigments in algae. Structure and reproduction of algae was written by Fritsch. He is known as father of phycology. Fritsch classified algae into 11 classes on the basis of type of pigments, nature of reserve food material and mode of reproduction. Read more>>
Biology Practice Test: Algae
When you've finished answering as many of the questions as you can, scroll down to the bottom of the page and check your answers by clicking 'get score'.
Dictyota dichotoma (Phaeophyceae)
1. What among the following do you consider the best evidence to show that two species of algae are closely related?
they both have same type of pigments
they both have reproduce sexually
they both respire and release carbondioxide
they both have same type of pigments
2. In eukaryotic algae and fungi, flagella and cilia of zoospores and gametes are
have 1+0 arrangement of fibrils
The peripherals fibrils are triplets and central are doublets
have 9+0 arrangement of fibrils
generally similar and have 9+2 arrangement of fibrils. The peripheral fibrils are doublelets and central fibrils are just canal like
3. Filaments of Ulothrix produce
Isogametes
Anisogametes
Heterogametes
None of these
4. Vaucheia, a siphonaceous alga, belongs to
Chlorophyceae
Xantophyceae
Cyanophyceae
Charophyceae
5. Trumpet hyphae in certain brown algae resemble
Tracheids
Trachea
Sieve tubes
Sclerenchymatous fibres
6. Non motile gamaetes are characteristically found in
Rhodophyta
Cyanophyta
Phaeophyta
Chlorophyta
7. Fairly good yield of rice can be had over a number of years without adding any nitrogenous manure because
they require very minute quantities of nitrogen.
Rice plants do not require any nitrogen
There are nitrogen fixing blue green algae in the rice fields
Their roots have nitrogen fixing bacteria associated with them
8. The algal component in lichen generally belongs to the class
Xanthophyceae
Phaeophyceae
Cyanophyceae
Rhodophyceae
9. Among the following which is obtained from algae
Agar agar
Wax
Chocolate
butter
10. Water bloom is generally caused by
Hydrilla
Bacteria
Blue green algae
Green algae
Score =
Correct answers:
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MCQ on Modern Techniques In Disease Diagnosis

1. The device used to study the activity of brain is
a)EEG
b)ECG
c)Autocatalyser
d)Dialyser

2. The techniques uses the body’s water molecules are the bases for its images
MRI scan
a)sonography
b) MRI
c)radioactive traces.
d)digital substraction angiography

3. Cross sectional image of internal body structure can be obtained by using this medical technique
a)ECG
b)CAT
c)NMR
d)ECG

4. Blood dialysis is also called
a) Artificial lung
b) Artificial kidney
c) Artificial heart
d) Artificial brain

5. During amniocentesis chromosomal abnormalities of the fetus can be detected by taking the sample of
a) Foetal blood
b) Mother’s blood
c) Body fluid from the mother
d) Fluid surrounding the foetus

6. ELISA is commonly used to detect
ELISA plate
a)Mumps
b)Rabies
c)AIDS
d)Tetanus

7. Who is considered as the father of electrocardiography?
a)Jenner
b)Purcell
c)Housfield
d)Einthovan

8. Which one of the following is an imaging technique?
a)MRI scan
b) ELISA
c)Widal test
d)ECG

9. The technique used to detect foetal movement is
a)PET
b)CT scan
c)PET
d) Ultrasound scan

10. First human EEG was recorded by
a)Purcell
b) Jeffrey
c) Hans Berger
d) Einthovan

11. ELISA is used to detect viruses where the key reagent is
a) catalase
b) DNA probe
c) RNAase
d)Alkaline phosphatase

12. Cornea transplantation is successful because
a)cornea is easy to preserve
b) cornea is easy available
c) cornea is not linked up with blood vascular and immune system.
d)the technique involved is very simple
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Answers
1. a)EEG
2. b) MRI
3. b)CAT
4. b) Artificial kidney
5. d) fluid surrounding the foetus
6. c)AIDS
7. d)Einthovan
8. a)MRI scan
9. d) Ultrasound scan
10. c) Hans Berger
11. d)Alkaline phosphatase
12. c) cornea is not linked up with blood vascular and immune system.
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Multiple Choice Questions on Digestive glands

1. Secretion of gastric juice is stimulated by
a) enterogastrin
b) gastrin
c) cholecstokini
d) None of these

2. Bile acts as activator of which enzyme
a) lipase
b) pepsinogen
c) pancreatic amylase
d) trypsinogen

3.HCI of the gastric juice
a)activates both pepsin and ptyalin
b) inactivates both pepsin and ptyalin
c) activates pepsin and inactivates ptyalin
d) activates ptyalin and inactivates pepsin

4. Cholecystokinin stimulates
a) pancreas
b) gall bladder
c) gastric gland
d) none of these

5. Brunner’s glands are present in
brunners gland
a)stomach
b) ileum
c) duodenum
d) oesophagus

6. Crypts of Lieberkuhn are present in
a)intestine
b)stomach
c) oesophagus
d)all of these

7. Succcus entericus is secreted by
a) Crypts of Lieberkuhn
b) Peyers patches
c) Auerbach’s plexus
d)Brunner’s gland

8. Oxyntic cells secrete
a) trypsin
b) HCI
c)NaoH
d)pepsin

9. The largest gland in the human body is
a)pancreas
b) brain
c) liver
d)gall bladder

10. The hepatic cells which act as phagocytes are
a)kuffer cells
b)acinar cells
c)Hansen’s cells
d)none of these
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Answers
1. b) gastrin
2. a) lipase
3. c) activates pepsin and inactivates ptyalin
4. b) gall bladder
5. c) duodenum
6. a)intestine
7. a) Crypts of Lieberkuhn
8. b) HCI
9. c) liver
10. a)kuffer cells
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Multiple Choice Questions on Proteins

16. 4-hydroxy proline is present in
a)      Collagen
b)      Plant cell wall
c)       Keratin
d)      Both plant cell wall and collagen

17. Peptide bonds between amino acids are highly stable and have a half-life of seven years in intracellular condition. This is due to
a)      High activation energy required for hydrolysis
b)      Low activation energy required for hydrolysis
c)       Peptide bond is a covalent bond
d)      Peptide bond is rigid and planar

18. Tri-peptide consists
a)      3 amino acids and 3 peptide bonds
b)      2 amino acids and 3 peptide bonds
c)       3 amino acids and 2 peptide bonds
d)      3 amino acids and 4 peptide bonds

19. All the following statements are true except
a)      Ornithine and citrulline are uncommon aminoacids
b)      Ornithine is an  intermediates in Urea cycle
c)       Ormithine and citrulline are uncommon amino acids present in many proteins
d)      Both ornithine and citrulline are intermediates in urea cycle

20. The characteristic strong absorbance of 280nm of proteins is due to
a)      All amino acids can absorb at 280nm
b)      Only Tryptophan and tyrosine can absorb at 280 nm
c)       Tryptophan is responsible for the absorbance
d)      Tryptophan, tyrosine and phenylalanine can absorb at 280 nm

21. The formation of cystine occurs at
a)      ER
b)      Golgi
c)       Cytosol
d)      Mitochondria

 22. Which of the following interaction contributes most in protein folding
hydrophobic interaction

a)      Covalent bond
b)      Ionic bond
c)       Hydrophobic interaction
d)      Vander walls interaction

23. Which of the following aminoacid has pKa near neutrality
a)      Tryptophan
b)      Arginine
c)       Histidine
d)      Asparagine

24. Desmosine is an unusual amino acid found in
a)      Myosin
b)      Elastin
c)       Troponin
d)      Actin

25. How many small peptides are formed upon cleavage by trypsin if a protein has 5 lysine residues
a)      4
b)      5
c)       6
d)      7
                       
26. EF-1α and EF-Tu are
a)      Analogs
b)      Homologs
c)       Paralogs
d)      Syllogs

27. All the statements  regarding peptide bond are true except
a)      Peptide bond is a co-valent bond
b)      Peptide bond is rigid and planar
c)       Peptide bond has partial double bond character
d)      Peptide bond is formed by non-condensation reaction

28. Αlpha-helix has
a)      3.6 residues/turn and  is a right handed helix
b)      3.8 residues/turn and is a right handed helix
c)       3.6 residues/turn and is a left handed helix
d)      3.8 residues/turn and is a left handed helix

29.Which of the following amino acids are rarely present in alpha helix
a)      Glycine and proline
b)      Proline and tryptophan
c)       Tryptophan and glycine
d)      Proline only

30. PDI is an enzyme involve in
a)      Protein synthesis
b)      Protein degradation
c)       Protein folding
d)      Protein quaternery structure formation
Free MCQ Test on Biomolecules->Amino acids->Proteins -> Protein Structure
Answers with explanation
 16.d) 
Both plant cell wall and collagen
Explanation: 4-hydroxyproline, 5-hydroxy lysine, selenocysteine, desmosine, carboxy glutamate all are uncommon  amino acids

17.a)
18.c) amino acids and 2 peptide bonds

19.c) 
Ormithine and citrulline are uncommon amino acids present in many proteins
Remember, these two amino acids are not present in any proteins.

20.d
Tryptophan, tyrosine and phenylalanine can absorb at 280 nm. These are aromatic amino acids. Tryptophan and tyrosine absorbs strongly at 280nm where as phenylalanine has comparatively low absorbance.

21.a) ER.
Two cysteine amino acids are linked by di-sulphide bond to form cystine. Di-sulphide bonds are formed only in the highly oxidizing environment of ER.

22.c Hydrophobic interaction (Bonds in Proteins)

23.c histidine has a pKa of 6.0 and has buffering capacity

24.b) Elastin

25.c) 6 Trypsin cleave at C-terminal of lysine or arginine residue

26.b) homologs.
EF-Tu elongation factor is involved in protein synthesis of bacteria. The protein counterpart in eukaryote is EF-1α. Both are members of the same family with a common ancestry.

27.d Peptide bond is formed by non-condensation reaction. Actually Peptide bond is formed by condensation reaction.

28.a) 3.6 residues/turn and is a right handed helix in all proteins. You have to read the options carefully before picking one.

29.a) glycine and proline.
Proline is an alpha helix terminator as it cannot form H- bond with other residues. Glycine is the simplest amino acid and has high conformational flexibility. Polymers of glycine form coiled structures entirely different from alpha helix.

30.c 
PDI (protein di sulphide isomerase) is an enzyme involved in shuffling of di sulphide bonds in protein folding. Refer our post protein folding.
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Multiple Choice Questions on Carbohydrates

36.  The most abundant biomolecule on earth
a) proteins
b) lipids
c) nucleic acids
d) Carbohydrates

37.  Carbohydrates are
a) polyhydroxy alkynes or aldehydes
b) polyhydroxy phenols or aldehydes
c) polyhydroxy ketones or aldehydes
d) polyhydroxy alkenes and aldehydes


38.  Carbohydrates occur naturally in
a) L- form and D-form
b) L- form only
c) D- form only
d) Dependent on the pH

39. Which of the following polysaccharide has α-1-3 linkage 
Dextran
a) cellulose
b) dextran
c) starch
d) glycogen

40. The most important interaction that contribute to polysaccharide folding 
a) Ionic bond
b) hydrophobic interaction
c) Vanderwalls interaction
d) hydrogen bond

41.  All of the following are extracellular heteropolyscacharides except
a) dextran
b) chondroitin
c) hyaluronate
d) dermatan sulpahte

42.  Functions of carbohydrates include
a) cell recognition
b) cell to cell interaction
c) imparting structure and store energy.
d) All of the above

43.  Lipopolysaccharide in the outer membrane is responsible for the antigenic property in
a) Gram positive bacteria
b) Gram positive and gram negative bacteria
c) Gram negative bacteria
d) Actinomycetes

44.   Many plasma glycoproteins has a terminal sialic acid residue that helps in
a) cell to cell recognition
b) cells interaction with extracellular matrix
c) protection form degradation by liver
d) generating signals that favours degradation by liver

45.   Lectins are
a) Carbohydrate degrading proteins
b) proteins that binds to carbohydrates with high affinity and specificity
c) are glycoproteins that binds to carbohydrates
d) are glycoproteins present in bacteria

46. Selectins are  
a) Plasma membrane lectins involved in cell-cell recognition
b) cytosolic lectins involved in intracellular signalling
c) Plasma membrane glycoproteins involved in cell to cell interaction
d) Plasma membrane glycoproteins that functions as second messengers

47. Lectins binds preferentially to
a) more polar region of the carbohydrate residue
b) less polar region of the carbohydrate residue
c) both polar and non-polar region of the carbohydrate residue
d) All of the above

48. Glycosylation takes place in  
a) SER and golgi
b) RER and golgi
c) SER, RER and golgi
d) RER, golgi and mitochondria

49. O- linked oligosaccharides are attached to the protein via  
a) OH group of serine or tyrosine
b) OH group of serine or threonine
c) OH group of tyrosine or threonine
d) OH group of threonine only

50. N-linked oligosaccharides are linked to protein via NH2 groups of Asparagine. The sequence containing asparagine is usually asp-X-ser/thr. X can be any amino acid except  
a) glycine
b) histidine
c) proline
d) serine
Free MCQ Test on Biomolecules -> Carbohydrates
Answers
36. d) carbohydrates
37. c) polyhydroxy ketones or aldehydes
38. c) D- form only
39. b) dextran
40. d) hydrogen bond
41. a) dextran
42. d) All of the above
43. c) Gram negative bacteria
44. c) protection form degradation by liver
45.  b) proteins that binds to carbohydrates with high affinity and specificity
46. a) Plasma membrane lectins involved in cell-cell recognition
47. a) more polar region of the carbohydrate residue
48. b) RER and golgi
49. b) OH group of serine or threonine
50. c) proline
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Multiple Choice Questions on Nucleic acid

1. The pentoses in nucleotides are 
a) in β-furanose form
b) in α-furanose form
c) Both
d) none of the above

2. To identify self DNA from non-self DNA, the self DNA may be
a) glycosylated
b) carboxylated
c) phosphorylated
d) methylated

3. Functions of nucleotide includes
a) information storage and transmission
b) storage of chemical energy
c) cell signalling
d) All of the above

4. Choose the best option
a) proteins has catalytic activity
b) Proteins and RNA have catalytic activity
c) Proteins, RNA and antibodies have catalytic activity
d) Proteins, RNA, antibodies and phospholipids have catalytic activity

5. The backbone of DNA is
a) hydrophilic
b) hydrophobic
c) nuetral
d) Both hydrophilic and hydrophobic

6. Which is the most stable form of DNA under normal physiological conditions
a) A-DNA
b) B-DNA
c) Z-DNA
d) H-DNA

7. As far as the absorbance of DNA at 260nm. Which of the following is correct?
a) individual nucleotides>ss DNA>dsDNA
b) dsDNA>ssDNA> individual nucleotides
c) ssDNA>dsDNA> individual nucleotides
d) absorbance remains same

8. Which of the following statement is true?
a) DNA is more stable than RNA in alkaline condition because of the presence of 3’OH
b) DNA is more stable than RNA in alkaline condition because of the presence of 2’ H compared to RNAs 2’OH
c) RNA is more stable than DNA in alkaline condition because of the presence of 2’ and 3’OH compared to DNAs 2’H and 3’OH
d) Both are equally stable in alkaline condition

9. Dehydration of DNA samples may induce the formation of
a) A-DNA
b) B-DNA
c) Z-DNA
d) H-DNA

10. An increase in temperature of a DNA sample causes change in
a) absorbance at 260nm
b) viscosity
c) phosphodiester linkage
d) absorbance and viscosity

11. RNA-DNA hybrids are
a) more stable than  DNA-DNA hybrid
b) more stable than  RNA-RNA hybrid
c) less stable than RNA-RNA hybrid
d) less stable than RNA-RNA hybrid and DNA-DNA hybrid

12. An increase Tm (melting temperature) for a ds-DNA may be due to high content of
a) A+G
b) A+T
c) C+G
d)none of the above

13. Thymine is present in
a) prokaryotic mRNA
b) mammalian mRNA
c) ribosomal RNA
d) tRNA

14RNA is genetic material in
a)  some virusus and prokaryotes
b) some viruses only
c) some virusus, prokaryotes and some primitive eukaryotes
d) none of the above

15. DNA has
a) autocatalytic function
b) heterocatalytic function
c) both autocatalytic and heterocatalytic function
d) none of the above

Free online MCQ test on:  Nucleic acid -> DNA -> DNA Structure-> RNA
Answers: 
1- a) in β-furanose form (closed 5-membered ring
2- d) methylated.
3- d) All of the above
4-    c) Proteins, RNA and antibodies have catalytic activity.
RNA with catalytic activity: ribozymes
Antibodies with catalytic activity-abzymes
5- a) hydrophilic. The OH group  of sugar residue form H-bond with water
6- b) B-DNA
7- a) individual nucleotides>ss DNA>dsDNA
The reason for absorbance (A260 in DNA) is N2 bases. In ss DNA, N2 bases are  exposed so more A260 than ds DNA. In free nucleotides, N2 bases are much more exposed and free so high A260 than ss and ds DNA.
8- b) DNA is more stable than RNA in alkaline condition because of the presence of 2’ H compared to RNAs 2’OH
9- a) A-DNA
10- d) absorbance and viscosity
11- d) less stable than RNA-RNA hybrid and DNA-DNA hybrid
12- c) C+G has three H-bonds compared to two in A=T. So more temperature is needed for denaturation.
13- d) tRNA. t RNA has thymine and many unusual bases.
14- b) some viruses only
15- c) both autocatalytic and heterocatalytic function
Autocataytic function: DNA replication
Heterocatalytisc function:  directs synthesis of RNA and proteins
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