Human Physiology Lecture Notes

Difference between Rod Cells and Cone Cells (Comparison Table)


Rod cells vs cone cells

Rod cells vs Cone Cells
Similarities and Differences between Rod Cells and Cone Cells

Rod cells and Cone cells are the two types of photoreceptor cells found in the retina of eyes. These cells are capable of absorbing light and converting the light into signals that can trigger a change in the membrane potential, which results in visual phototransduction. In other words, these cells assist in vision in presence of light.

Rod cells: A type of photoreceptor cells in the eye found concentrated at the outer edges of the retina. Rod cells are responsible for vision in low light conditions.

Cone cells: The second type of photoreceptor cell in the eye concentrated in the fovea of the retina. Cone cells are responsible for the vision in bright light and colour vision.

rod vs cone cells

image source: wikipedia

The present post explains the similarities and differences between Rod cells and Cone cells with a comparison table.

Similarities between Rods and Cones

Ø  Both rods and cones are photoreceptor cells of the eye.

Ø  Both can absorb photon (light)

Ø  Both cells possess photoreceptor proteins to absorb the photons (light).

Ø  Both are modified nerve cells.

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Zoology lecture notes and study materials

Kerala PSC Zoology Lecturer Previous Year Question Paper 2014 – Original Solved (Part 1 of 5)


Zoology Lecturer Paper

Kerala PSC Zoology Lecturer / Assistant Professor Recruitment Exam 2014
Question Paper (Q. Code 56/2014)

Original solved question paper of Kerala PSC Zoology Lecturer/Assistant Professor examination conducted by Kerala PSC (Kerala Public Service Commission) on 29/04/2014 (Question Paper Code 56/2014) for the appointment of Zoology Lecturer/Assistant Professor in Government Colleges of Kerala under the Directorate of Collegiate Education, Trivandrum, Kerala. Questions are in MCQ (Multiple Choice Questions) format.

Part – 1 of 5 (Questions 1 – 20)

1. The naturalist who independently conceived the idea of Natural Selection along with Darwin:

a.       Alfred Russell Wallace
b.      Charles Lyell
c.       Joseph Hooker
d.      John Henslow

Ans. (a)

2. The theory proposed by Stephen Jay Gould and Niles Eldredge to explain Evolution:

a.       Theory of Genetic drift
b.      Theory of punctured equilibrium
c.       Theory of genetic equilibrium
d.      Theory of Orthogenesis

Ans. (b)

3. A system of classification based on the phylogenetic relationships and evolutionary history of groups of organisms:

a.       Phenetics
b.      Phyletics
c.       Cladistics
d.      Phylogenetics

Ans. (c)

4. Eight kingdom classification was proposed by:

a.       R.H. Whittaker
b.      Carl Woese
c.       Carlous Linnaeus
d.      Cavalier Smith

Ans. (d)

5. Protein that was used to create the first phylogenetic tree based on molecular data:

a.       Cytochrome A
b.      Cytochrome B
c.       Cytochrome C
d.      Cytochrome D

Ans. (c)

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Zoology lecture notes and study materials

Lecturer In Zoology: Kerala PSC Previous Year Question Paper 2014 – Original Solved (Part 2 of 5)


Kerala PSC Old Question papers

Kerala PSC Zoology Lecturer / Assistant Professor Recruitment Exam 2014
Question Paper (Q. Code 56/2014)

Original solved question paper of Kerala PSC Zoology Lecturer/Assistant Professor examination conducted by Kerala PSC (Kerala Public Service Commission) on 29/04/2014 (Question Paper Code 56/2014) for the appointment of Zoology Lecturer/Assistant Professor in Government Colleges of Kerala under the Directorate of Collegiate Education, Trivandrum, Kerala. Questions are in MCQ (Multiple Choice Questions) format.

Part – 2 of 5 (Questions 21 – 40)

21.  From the following, select the correct combination. The immunoglobulin class produced in a primary response to an antigen and the first immunoglobulin to be synthesized by the neonate are:

a.       IgM, IgM
b.      IgM, IgG
c.       IgM, IgA
d.      IgM, IgD

Ans. (a)

22.  In Grave’s disease, auto-antibodies:

a.       Bind to receptor for TSH
b.      Its action mimic the normal action of TSH
c.       Over stimulate the thyroid
d.      All the above

Ans. (d)

23.  Which of the following is correct with respect to the function of complement system?

a.       Lysis
b.      Opsonization
c.       Clearance of immune complexes
d.      All the above

Ans. (d)

24.  Haptens are:

a.       Antigenic
b.      Immunogenic
c.       Both antigenic and immunogenic
d.      Non-antigenic and non-immunogenic

Ans. (a)

25.  George Kohler and Cesar Milstein are associated with:

a.       Transplantation
b.      Hybridoma technology
c.       Vaccine development
d.      Complement system

Ans. (b)

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Zoology lecture notes and study materials

KPSC Zoology Lecturer Exam Previous Year Question Paper 2014 – Original Solved (Part 3 of 5)


Zoology Lecturer previous papers

Kerala PSC Zoology Lecturer / Assistant Professor Recruitment Exam 2014
Question Paper (Q. Code 56/2014)

Original solved question paper of Kerala PSC Zoology Lecturer/Assistant Professor examination conducted by Kerala PSC (Kerala Public Service Commission) on 29/04/2014 (Question Paper Code 56/2014) for the appointment of Zoology Lecturer/Assistant Professor in Government Colleges of Kerala under the Directorate of Collegiate Education, Trivandrum, Kerala. Questions are in MCQ (Multiple Choice Questions) format.

Part – 3 of 5 (Questions 41 – 60)

41.  U-rich mRNA participate in pre-mRNa splicing are:

a.       U1, U2, U3, U4, U5
b.      U1, U3, U5, U7, U5, U9
c.       U2, U4, U6, U8, U10
d.      U1, U2, U4, U5, U6

Ans. (d)

42.  Extent of interference can be measured by coefficient of co-incidence. Therefor:

a.       C = (Expected frequency of double cross overs/Observed frequency of double cross overs) X 100
b.      C = (Expected frequency of double cross overs/Observed frequency of double cross overs)
c.       C = (Observed frequency of double cross overs/Expected frequency of double cross overs)
d.      C = (Observed frequency of double cross overs / Expected frequency of double cross overs) X 100

Ans. (c)

43.  During replication in E.coli the unwinding of DNA is catalyzed by:

a.       DNA helicase
b.      ssDNA binding protein
c.       DNA topoisomerase
d.      DNA polymerase

Ans. (a)

44.  47XXY in man indicates:

a.       Down’s syndrome
b.      Klinefelter’s syndrome
c.       Turner syndrome
d.      Cri-du-chat syndrome

Ans. (b)

45.  Trichothiodystrophy is associated with:

a.       Structural gene mutation
b.      Defect in nucleotide excision repair
c.       Defect in DNA metabolism
d.      Defect in mismatch repair mechanism

Ans. (b)

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Zoology lecture notes and study materials

Kerala PSC Zoology Lecturer Previous Year Question Paper 2014 – Original Solved (Part 4 of 5)


Assistant professor Jobs in Zoology

Kerala PSC Zoology Lecturer / Assistant Professor Recruitment Exam 2014
Question Paper (Q. Code 56/2014)

Original solved question paper of Kerala PSC Zoology Lecturer/Assistant Professor examination conducted by Kerala PSC (Kerala Public Service Commission) on 29/04/2014 (Question Paper Code 56/2014) for the appointment of Zoology Lecturer/Assistant Professor in Government Colleges of Kerala under the Directorate of Collegiate Education, Trivandrum, Kerala. Questions are in MCQ (Multiple Choice Questions) format.

Part – 4 of 5 (Questions 61 – 80)

61.  A three dimensional image of a bacterium is achieved by using:

a.       Phase contrast microscopy
b.      Transmission electron microscopy
c.       Scanning electron microscopy
d.      Bright field microscopy

Ans. (c)

62.  Tow dimensional gels are used to:

a.       Separate DNA fragments
b.      Separate DNA from RNA
c.       Separate different proteins
d.      Observe protein in two dimensions

Ans. (c)

63.  In reversed phase HPLC:

a.       A hydrophobic stationary phase is combined with a polar mobile phase
b.      A hydrophobic stationary phase is combined with a polar mobile phase
c.       A hydrophobic stationary phase is combined with a non-polar mobile phase
d.      A hydrophilic stationary phase is combined with anon-polar mobile phase

Ans. (b)

64.  Human genome comprise of:

a.       20 billion nucleotides
b.      5 million nucleotides
c.       3.1 billion nucleotides
d.      5 billion nucleotides

Ans. (c)

65.  CpG islands and codon bias are tools used in eukaryotic genomics to

a.       Final regular sequences
b.      Identify a gen’s function
c.       Identify open reading frames
d.      Look for DNA binding domains

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