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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mcq biology

Ecology Multiple Choice Questions Part 2 with Answer Key


environmental science test questions and answers

ECOLOGY MCQ-02
(Biology / Life Sciences MCQ: Multiple Choice Questions in Biochemistry)

MCQ on Ecosystem: Introduction Part 2
(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 is NOT a characteristic of population?

a.       Sex ratio
b.      Natality
c.       Mortality
d.      Stratification

2. Which decade has been designated as the ‘Decade of Biodiversity’ by United Nations?

a.       2021-2030
b.      2011-2020
c.       2001-2010
d.      1991-2000

3. Decomposers which specifically act on the fecal matter of other organisms are called as:

a.       Heterophagic
b.      Allophagic
c.       Coprophagic
d.      Paraphagic

4. In a pond ecosystem, the top area where the production is greater than respiration (P/R >1) is termed as:

a.      Limnetic zone
b.      Profundal zone
c.       Benthic zone
d.      Tidal zone

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mcq biology

Ecology Multiple Choice Questions Part 1 with Answer Key


Ecology Quiz

ECOLOGY MCQ-01
(Biology / Life Sciences MCQ: Multiple Choice Questions in Biochemistry)

Ecosystem Concepts : Introduction Part 1/2
(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. The natural place where the organism or communities live is known as:

a.       Niche
b.      Habit
c.       Habitat
d.      Biome

2. Any features of an organism or its part which enable it to exist under conditions of its habitat is known as:

a.       Adaptive variation
b.      Adjustment
c.       Acclimatization
d.      Adaptation

3. According to Shelford’s low of tolerance, an organism with wide tolerance limit for environmental factor usually show:

a.       Wide distribution with low population size
b.      Wide distribution with high population size
c.       Narrow distribution with low population size
d.      Narrow distribution with high population size

4. Plants which grow under direct sunlight and those growing under shade are called as _______ and _______ respectively.

a.       Heliophytes and Sciophytes
b.      Sciophytes and Heliophytes
c.       Psamophytes and Heliophytes
d.      Heliophytes and Psamophytes

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Botany lecture notes

Kerala PSC Botany Lecturer Recruitment Test 2003 – Original Solved Question Paper Part 1


Kerala psc assistant professor recruitment

Kerala PSC Botany Lecturer / Assistant Professor Question Paper (250/2003)

Original solved question paper of Kerala PSC Botany Lecturer/Assistant Professor examination conducted by Kerala PSC (Kerala Public Service Commission) for the appointment of Botany Lecturer/Assistant Professor in Government Colleges of Kerala under the Directorate of Collegiate Education, Trivandrum, Kerala. Question Paper Code Number 250/2003. Questions are in MCQ (Multiple Choice Questions) format. Detailed answer key with explanations are given at end of each set.

Part – 1/5 (Questions 1 – 20)

1. Shuttle vectors are:

a.       Capable of replicating in two different hosts
b.      Produce in two different hosts
c.       Produced in one microbe but multiply in another
d.      Travel between host and parasite

2. The outer layer of the cell wall in gram negative bacteria is

a.       Secondary wall layer
b.      Primary wall membrane
c.       Peri-plasmic membrane
d.      Capsule membrane

3. A bacterium used as bio-insecticide by creating a transgenic plant:

a.       Bacillus thuringiensis
b.       Streptococcus cremoris
c.       Bacillus licheniformis
d.      Thiobacillus cervicii

4. The heat content which is exchanged between isothermal system and its surrounding in bioenergetics change is described as:

a.       Entropy change
b.      Activation energy change
c.       Free energy change
d.      Enthalpy change

5. Carpogonia are:

a.       Diploid structures
b.      Haploid structures
c.       Triploid structures
d.      Tetraploid structures

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Botany lecture notes

Meristematic Tissue: Structure and Classification (Key Points)


different types of meristematic tissues

What are meristems?

Ø  Meristem is a type plant tissue composed of an undifferentiated mass of cells.

Ø  They are rapidly dividing cells found in the growing portions of the plant and they give rise various plant organs.

Ø  The primary function of meristem is to assist in plant growth.

Ø  Living cells other than meristem can also give rise new cells; however, the meristems carry on such activity indefinitely.

Ø  Meristematic cells not only add new cells to the plant body but also perpetuate themselves.

Ø  Meristematic cells when divide, some portions of division do not differentiate into adult cells but remain meristematic.

Ø  The term meristem was first proposed by Karl Wilhelm von Nägeli (1817–1891) in his book Beiträge zur Wissenschaftlichen Botanik (“Contributions to Scientific Botany”).

Ø  The word meristem is derived from a Greek word ‘merizein’ meaning ‘to divide’.

Characteristics of Meristematic Cells

Ø  The characteristic features of meristematic cells are summarized in the post: Characteristic Features of Meristematic Cells

Classification of meristems

Ø  Meristems are classified according to TWO criterions

(1). Classification based on position in the plant body

§  Apical meristem

§  Lateral meristem

§  Intercalary meristem

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