Botany lecture notes

Botany Lecturer: Kerala PSC Previous Year Question Paper (Original Solved) 2003 – Part 2/5

botany assistant professor psc

Kerala PSC Botany Lecturer / Assistant Professor Original Solved Question Paper: 2003 Exam
(Question Paper Code: 250/2003)

Original solved question paper of Kerala PSC Botany Lecturer/Assistant Professor examination conducted by Kerala PSC (Kerala Public Service Commission) for the recruitment / appointment of Botany Lecturer/Assistant Professor in Government Colleges of Kerala under the Directorate of Collegiate Education, Trivandrum, Kerala. The test was conducted in the year 2003 and the Question Paper Code Number is 250/2003. All questions were in MCQ (Multiple Choice Questions) format. A detailed answer key with explanations is given at end of each set.

Part – 2/5 (Questions 21 – 40)

21.  Pro-phage is:

a.       DNA incorporated with the host DNA
b.      DNA or RNA in the early stages of infection
c.       DNA of bacterial cell before viral infection
d.      DNA present is only an incomplete fragment

22.  ‘Bars of Sanio’ are the crescent shaped bars of cellulose present:

a.       Near the pits on tracheids of Gymnosperm wood
b.      On the secondary wood of Angiosperms
c.       On the tracheids of Pteridophytes
d.      On the extensive periderm of Cycas wood

23.  Bryophytes exhibit alternation of generation:

a.       Homomorphic
b.      Heteromorphic
c.       Isomorphic
d.      No definite change in life cycle

24.  DNA sequences that suppress promoter activity are called:

a.       Enhancers
b.      Reporters
c.       Responsive elements
d.      Silencers

25.  Synthetic seeds are produced by:

a.       Encapsulation of somatic embryo with matrix for storing
b.      Cryopreservation of somatic embryo for long storage
c.       Preservation of seeds by covering with organic polymers
d.      Encapsulation of normal seed with a resistant matrix

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mcq biology

MCQ on Environmental Science with Answer Key

ecology quizzes

(Biology / Life Sciences MCQ: Multiple Choice Questions in Ecology)

MCQ on Environmental Sciences
(Sample/Model/Practice Questions for CSIR JRF/NET Life Science Examination, ICMR JRF Exam, DBT BET JRF Exam, GATE BT and XL Exam, ICAR JRF NE Exam, PG Entrance Exam, JAM Exam, GS Biology Exam and Medical Entrance Exam)


1. Which of the following statement best describe a seral community in an ecological succession?

a.       Less stable
b.      More aggressive
c.       More diversity but less stability
d.      More adaptability but less stability

2. Which of the following is NOT an adaptation of a hydrophyte?

a.       Less parenchyma in the stem
b.      Less cuticle over the epidermis
c.       Stomata on the upper side of the leaf
d.      Poorly developed root system

3. The leaf like structure seen in the Acacia plant is:

a.       Phyllode
b.      Cladode
c.       Phylloclade
d.      Cladophyll

4. Mycorrhizal symbiotic association in plants with fungi helps in the absorption of which component from the soil?

a.       Nitrates
b.      Nitrites
c.       Ammonia
d.      Phosphates

5. The process of dendrochronology cannot be applied to plants living in___

a.       Trees in the tropical areas
b.      Trees in the temperate areas
c.       Trees growing in the region of equators
d.      Trees growing in the alpine regions

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mcq biology

Ecology MCQ 003 with Answer Key

MCQ on Ecology

(Biology / Life Sciences MCQ: Multiple Choice Questions in Ecology)

MCQ on Ecosystem and Environment
(Sample/Model/Practice Questions for CSIR JRF/NET Life Science Examination, ICMR JRF Exam, DBT BET JRF Exam, GATE BT and XL Exam, ICAR JRF NE Exam, PG Entrance Exam, JAM Exam, GS Biology Exam and Medical Entrance Exam)

(1). In ecology, the term ‘biocenosis” specifically explains:

a.       Ecological study of communities
b.      Ecological study of individual species
c.       A group of organism inhabiting a particular area
d.      A group of many species of plants and animals living together in a natural area

(2). The aquatic animals in the polar region survive even in freezing temperature. This can be explained by:

a.       The very thick layer of fat deposition in their skin
b.      By migrating to temperate region during cold times
c.       Due to the high density of water at 4oC
d.      Due to the neutral pH of the soil at very cold condition

(3). Which among the following is the most abundant molecule in the atmosphere?

a.       CO2
b.      Argon
c.       Methane
d.      Water vapour

(4). Which of the following explain thermal stratification?

a.       Non viability of seeds at higher temperature
b.      Adjustment of body temperature according to the temperature of surroundings
c.       Layers of water in a pond with different temperature
d.      Cycling events in the ocean due to lunar cycle

(5). Which of the following temperature range is known as epilimnion?

a.       8 – 20
b.      21 – 22
c.       5 – 9
d.      9 – 24

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Botany lecture notes

Difference between Protoxylem and Metaxylem: A Comparison Table

classification of xylem

Protoxylem vs Metaxylem
Similarities and Differences between Protoxylem and Metaxylem

Vascular bundles (fascicles) are the component of the stelar system in higher plants and their main function is the conduction of water, minerals and food materials. Typically the vascular bundle composed of xylem and phloem arranged together as bundles. In a young stem, both in dicots and monocots, the xylem of vascular bundles are differentiated into PROTOXYLEM and METAXYLEM based on the structural and functional difference of their elements. The present post describes the similarities and differences between Protoxylem and Metaxylem in a primary vascular bundle of a young stem.

Similarities between Protoxylem and Metaxylem

Ø  Both protoxylem and metaxylem can conduct water and minerals.

Ø  Both components contain living and dead cells.

Ø  Both are developed from the primary meristem, the pro-cambium.

Ø  Both contain tracheids, vessels and parenchyma.

Ø  Protoxylem and metaxylem develop only in primary vascular bundles.

Differences between Protoxylem and Metaxylem

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Free Net Life Science Study Materials

CSIR JRF NET Life Sciences Exam: December 2016: Model Question Paper- Set 1/5

csir net jrf december 2016 question paper

CSIR JRF NET Life Sciences Examination: December 2016
Model Question Paper with Answer Key and Explanations – Set 1/5

1. The metal component of Nitrogenase enzyme is:

a.       Mananese
b.      Molybdenum
c.       Copper
d.      Zinc

2. The only plant hormone which is NOT translocated from the cells producing it:

a.       Auxin
b.      Ethylene
c.       Cytokinin
d.      Gibberillic acid

3. Ribosomal rRNA in eukaryotes are transcribed by:

a.       RNA Polymerase I
b.      RNA Polymerase II
c.       RNA Polymerase III
d.      RNA Polymerase I and III

4. RNA-DNA hybrid always adopt A form because of:

a.       Steric hindrance of –OH group in RNA
b.      Steric hindrance of –OH group in DNA
c.       Coiling of the molecule
d.      Presence of Uracil base in RNA

5. Which plant is the most efficient converter of solar energy?

a.       Wheat
b.      Sugarcane
c.       Rice
d.      Banana

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