Question

Aim of experiment: Identification of parenchyma,collenchyma and sclerenchyma tissues in plants, stripped,smooth and cardiac muscle fibre and nerve cells in animals from prepared slides .Drawing of their labelled diagram
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Answer 1

Answer:

PROCEDURE

Observe the prepared slides of all the plant tissues one by one.

First focus the slide at low power and then observe it at high power.

Study the characters and draw the diagrams in your notebook.

OBSERVATIONS

IDENTIFYING FEATURES

I. Parenchyma

Cells of Parenchyma tissue are isodiametric.

Intercellular spaces are present in between the cells.

Parenchymatous cells possess large central vacuole and peripheral cytoplasm with a nucleus.

These are generally present in the soft parts of plants like leaves, roots, flowers, etc.

The important functions of parenchymatous cells are storage, photosynthesis, etc.

II. CoIIenchyma

Collenchymatous cells are somewhat oval to elongated.

Each cell possesses large central vacuole and peripheral cytoplasm with prominent nucleus.

Thickenings are present at corners of cells. Thickening comprise of cellulose and pectin.

Intercellular spaces are absent.

Collenchymatous cells are commonly present below the epidermis in petiole, leaves and stems. Its

main function is to provide mechanical strength.

III. Sclerenchyma

Cells of sclerenchyma tissue are dead with highly thickened walls.

Thickenings consist of lignin.

There are two types of sclerenchyma cells:

fibres which are elongated cells with tapering ends and

sclereids (also called stone cells), which are roughly isodiametric cells with narrow cavities.

Sclerenchymatous cells have pits which act as connections with adjacent cells.

The main function of sclerenchyma is to provide support and mechanical strength to the plant.

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AIM

To identify striped muscle fibres and nerve cells in animals, from prepared slides and to draw their labelled diagrams.

MATERIALS REQUIRED

Prepared slides of non-striated, striated and cardiac muscle fibres and nerve cells, compound microscope.

I. Striated Muscles or Striped or Skeletal Muscles

Striated muscle cells are cylindrical, elongated and enclosed in a membrane called sarcolemma.

These muscle cells are multinucleated.

Striated muscles show presence of light and dark bands which gives it striped appearance.

These muscles are present attached to the skeleton of the body.

They are voluntary muscles (i.e., work according to our will).

II. Non-striated Muscles or Unstriped or Smooth Muscles

The cells are spindle-shaped.

Nucleus is centrally located.

These muscles do not show striations {i.e., no light and dark bands).

Non-striated muscles are involuntary in nature.

They are commonly found in alimentary canals and blood vessels.

III.Cardiac Muscles

Cardiac muscle cells are long, branched and uninucleate.

These show the presence of intercalated discs.

They show alternate light and dark bands.

These are involuntary muscles and responsible for rhythmic contraction and relaxation of heart.

Cardiac muscles are present only in walls of heart.

NERVE CELL

Nerve cell comprises of a cell body or cyton with a single nucleus and cytoplasm.

Many small cytoplasmic projections arise from cyton which are called dendrons. The dendrons divide further to form dendrites.

A long cytoplasmic projection arising from cell body is called axon.

A myelin sheath is present over the axon in some nerve fibres, these are called myelinated nerve fibre and when myelin sheath is absent these are called non-myelinated nerve fibres.

Myelin sheath is not continuous. There are gaps along the entire length. Each gap is called nodes of Ranvier.

Nerve cells help in conduction of nerve impulse.

HOPE IT HELPS UH!

MARK AS BRAINLIEST!

Answer 2

Explanation:

Experiment

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