mcq biology

MCQ on Environmental Science with Answer Key


ecology quizzes

ECOLOGY MCQ-04
(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

ECOLOGY MCQ-03
(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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Botany lecture notes

Anatomy of Dicot Stem: The Primary Structure – Key Points with PPT


Stem Structure Anatomy

Anatomy of Dicot Stem
Anatomy of the Primary Structure of Dicot Stem

“Biology is the study of complicated things that have the appearance of having been designed with a purpose….”
Richard Dawkins

Ø  The anatomy of dicot stem is studied by a T.S. (transverse section) took through the internode of the stem.

Ø  The components of cortex and stele are together known as Ground Tissue.

Ø  Anatomically the dicot stem has the following regions:

(1). Epidermis

(2). Cortex

a).  Hypodermis
b).  Outer cortex
c).   Inner cortex
d).  Endodermis

(3). Stele

a).  Pericycle
b).  Vascular bundles
c).  Medullary rays
d).  Pith

(1). Epidermis

Ø  Epidermis is the outermost layer, composed of parenchymatous cells.

Ø  Usually, epidermis composed of single layer of cells.

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