Dr PS Verma VK Aggarwal Class 9 Biology 3rd Chapter Tissues Solution

Dr PS Verma Dr. VK Aggarwal Solution Class 9 Biology 3rd Chapter “Tissues” in here.

Short Answer Type Questions Answers (Carrying 2 marks each) Page No. 169

(1) The importance of tissues:-

(i) formation of tissues has brought about a division of labour in multicellular organisms.

(ii) Tissues become organized to form organs and organs into organ systems.

(2) This is because plants are autotrophic organisms that’s why they prepare their own food by photosynthesis. Plants are also stationary organisms. They do not have to move from place to place In search of food.

Whoever, Animals are heterotrophic organisms. They have to move in search of food from place to place as well mate, and find shelter.

(3) The difference plant tissues and animal tissues are following:-

(i) In plants dead supportive tissues are more abundant as compared to living tissues whoever, In multicellular animals living tissues are more coomon as compared to dead tissues.

(ii) Plant tissue require less maintenance energy whoever animal tissue require more maintenance energy.

(iii) Organisation of plant tissue is simple whoever Organisation of animal tissue is complex.

(4) Intercalary meristems:- They are located at the base of leaves or internode.

Ex: STEMS of grasses and other monocots. Such tissue also occur below the nodes.

(5) (a) The main function of Apical meristem:- Apical meristem brings about the elongation of the root and stem. It results in an increase in the height of the plant, which is called primary growth.

(b) Lateral meristem:- It causes the stem / root to increase diameter and girth.

(6) Tissues composed of single type of cells called simple tissue.

Three Different type are following:

(i) Parenchyma: Parenchyma tissue consist of thin walled living cells.

(ii) Collenchyma:- Collenchyma tissue consist of cells having localize thickening in their cell walls.

(iii) Sclerenchyma:- This tissue are dead cells and they are devoid of protoplasm.

Page No. 170

(7) Parenchyma tissue- Figure 3.8 (Page No. 127)

Collenchyma:- Figure 3.10 (Page Nom 129)

(8) Figure 3.18 Page no. 135

(9) Figure 3.17 Page No. 134

(10) Two function of Collenchyma are following:-

(i) Collenchyma provides mechanical support and elasticity.

(ii) Collenchyma allows easy bending in various parts of a plant without actually breaking it.

(11) Sclenrenchyma:- This tissue are dead cells and they are devoid of protoplasm. The cell wall of Sclerenchyma are greatly thickened of lignin. Such cell walls are called ligified.

(12) The difference between Xylem and Pholem are following:-

(i) Xylem conducts water and minerals whoever Pholem conducts organic solutes of food materials.

(ii) Xylem conduction is mostly unidirectional whoever Pholem conduction may be biodirectional.

(iii) Xylem conducting channels or tracheary elements are tracheids and vessels whoever Pholem conducting channels are sieve tubes.

(13) The difference between Vessels and Tracheids are following:

(i) Vessels are very long tube like structures formed by a row of cells placed end to end. The transvers walls between the vessel elements are partially or completely dissolved to form continuous channels or water pipes.

Whoever Tracheids are elongated cells with tapering ends. They also conduct water. So trachids do not have open ends like the vessels.

Short Answer Type Questions (Carrying 3 marks each)

(1) The different types of elements present in phloem are

(i) Sieve tubes:- Sieve tubes are slender, tube like structures, composed of elongated thin walled cells, place end to end.

(ii) Companion cells:- Generally associated with the sieve tube is a small thin walled cell containing dense and very active cytoplasm and large elongated nucleus.

(iii) Phloem parenchyma:- These are thin walled, living cells of parenchyma of phloem.

(iv) Phloem fibres:- These are thick walled, elongated spindle-shaped dead cells which posses narrow lumen.

(2) This are the elements of xylem. Their function is to carry water and mineral salts in upward direction from the roots to different part of shoots.

(3) The function of Parenchyma: (i) Parenchyma serves as a packing to fill the spaces between other tissues and maintain the shape and firmness of the plant due to its turgid cells.

(ii) Due to turgidity property, parenchyma acts as a primary support to the stem of herbaceous plants.

The function of Collenchyma:-

(i) Collenchyma is a mechanical tissue in young dicotyledonous stems and provides mechanical support and eslasticity.

(ii) Collenchyma allows easy bonding in various parts of a plant without actually breaking it.

The function of Sclerenchyma:

(i) Sclerenchyma gives strength, rigidity, flexibility and elasticity to the plant body and enables to withstand various strains.

(4) The difference between parenchyma and collenchymas are following:-

(i) The tissue of parenchyma consists of thin walled living cells whereas The tissue of Collenchyma consists of cells having localized thickening in their cell walls.

(ii) Pare4nchyma is distributed in almost all the parts of the plant body whereas, Collenchyma occurs mostly in the aerial parts of the plants and is restricted to the other layers.

(iii) The living cells of parenchyma assimilate and store food. Whereas Collenchyma is a chief mechanical tissue in parts of a young plant particularly in the young dicotyledonous stems.

(5) The difference between Collenchyma and Sclerenchyma are following:-

(i) Collenchyma consists of living cells whereas, Sclerenchyma consists of dead cells.

(ii) Collenchyma cells contain cytoplasm whereas, Sclerenchyma cwlls are empty.

(iii) Collenchyma cell walls are cellulosic whereas, Sclerenchyma cell walls are lignified.

(6) The function of Xylem are following:-

(i) Carry water and mineral salts upward from the root to different parts of shoots.

(ii) The give mechanical strength to the plant body.

(7) The name of different types of elements found in Xylem are- Tracheids, Vessels or tracheae, Xylem parenchyma and Xylem Sclerenchyma.

(8) The function of Phloem are following:

Phloem transports photosynthetically prepared food materials from the leaves to the storage organs and later from storage organs to the growing regions of the plant body.

(9) The names of different types of plant tissue are following:-

Plant tissue are classified in 2 forms (i) Meristematic tissue (ii) Permanent tissue.

Meristematic tissue are categorized in thrice, namely Apical, Lateral and Intercalary.

Permanent tissue are categorized in twos namely, Simple and Complex.

Simple tissue are classified in 3s, namely Parenchyma, Collenchyma and Sclerenchyma.

Complex tissue are categorized in 2s, namely phloem and Xylem.

(10) Sieve tubes are slender, tube like structures composed of elongated thin walled cells, palced end to end. Their end walls are perforated by numerous pores and are called sieve plates. Walls of sieve tubes are perforated. The nucleus of each sieve cell degenerates at maturity, however cytoplasm persists in the mature sieve tube elements. The cytoplasm of one sieve tube element is continuous with those of other sieve elements above and below due to cytoplasmic connections passing through the pores of the sieve plate.

(11) The four function of Epithelial tissue are following:-

(i) These cells protect the underlying cells from drying, injury and chemical effects.

(ii) They protect the body from viral or bacterial infection.

(iii) Inside the body, epithelial cells form lining of mouth and alimentary canal and protect these organs.

(iv) Epithelial tissues help in absorption of water and nutrients.

Name one specific place in the body is Mouth where each function is carried out.

(12) The three muscles are :

(i) Striated muscles-

(ii) Smooth muscles-

(iii) Cardiac muscles:-

(13) (i) Neuron – Nervous Tissue

(ii) Dendrite – Nervous Tissue

(iii) Cilia – Ciliated Epithelium

(iv) Collagen fibres – Connective Tissue

(v) Elastin fibre – Connective Tissue

(14) Osteoblast:- Provides shape to the body.

Chyondroblast:- Provided support and flexibility to the body parts.

Globlet cell:- It is a mucus secreting epithelial cell which secrets mucus.

Neuron:- The dendrites receive impulses and the axon takes impulses away from the cell body.

Muscle cell:- They undergo rapid contraction for locomotion.

(15) The nerve cell have the ability to receive stimuli from within or outside the body and to conduct impulses to different parts of the body.

(ii) The impulse travels from one neuron to another neuron.

(16) Bone provide shape to the body, It provide skeletal support to the body.

Cartilage provides support and flexibility to the body parts.

Ligaments are elastic structure which connects bones to bones.

(17) (a) Adipose tissues.

(b) Ciliated epithelium.

(18) Three function of Blood are following:

(i) It transports nutrients, hormones and vitamins to the tissues and transports excretory products from the tissue to the liver and kidney.

(ii) The Red Blood cell carry Oxygen to the tissues for the oxidation of food stuff.

(iii) Blood platelets disintegrate at the site of injury and help in the clotting of blood.

(19) The different tissues in animals

Epithelial tissue, Muscular tissue, Connective tissue and Nervous tissue.

(20) Figure 3.35 (Page No. 147)

(21) Figure 3.27 Page No. 140

Long Answer Type Questions (Carrying 5 marks each) Page No. 170

(1) The different types of tissue in plants are – (i) Meristematic tissue (ii) Permanent tissue.

Meristematic tissue are categorized in thrice, namely Apical, Lateral and Intercalary.

Permanent tissue are categorized in twos namely, Simple and Complex.

Simple tissue are classified in 3s, namely Parenchyma, Collenchyma and Sclerenchyma.

Complex tissue are categorized in 2s, namely phloem and Xylem.

Simple Tissue:-

These tissues are composed of cells which are structurally and functionally similar. Tissues composed of single type of cells are:-

(i) Parenchyma: Parenchyma serves as a packing to fill the spaces between other tissues and maintain the shape and firmness of the plant due to its turgid cells.

(ii) Collenchyma: Collenchyma is a mechanical tissue in young dicotyledonous stems and provides mechanical support and elasticity.

(iii) Sclerenchyma: This tissue are dead cells and they are devoid of protoplasm. The cell wall of Sclerenchyma are greatly thickened of lignin. Such cell walls are called lignified.

(2) Meristematic tissue:-

Cells of Meristems divide continuously and help in increasing the length and girth of the plant. Meristematic tissues are growth tissues and are found in the growing regions of the plant.

Classification of Meristematic Tissue:-

(i) Apical Meristems:- These are situated at the growing tip of stems and roots ex. At shoot6 apex and root apex. Apical meristems are also found at apices of the leaves.

(ii) Lateral meristems:- These are found beneath the bark and in vascular bundles of dicot roots and stems.

(iii) Intercalary meristems:- They are located at the base of leaves or internode.

(3) These tissues are composed of cells which are structurally and functionally similar. Tissues composed of single type of cells are:-

(i) Parenchyma: Parenchyma serves as a packing to fill the spaces between other tissues and maintain the shape and firmness of the plant due to its turgid cells.

(ii) Collenchyma: Collenchyma is a mechanical tissue in young dicotyledonous stems and provides mechanical support and elasticity.

(iii) Sclerenchyma: This tissue are dead cells and they are devoid of protoplasm. The cell wall of Sclerenchyma are greatly thickened of lignin. Such cell walls are called lignified.

(4) The complex tissues consist of more than one type of cells having a common origin.

Complex tissue are the following 2 types:

(a) Xylem:- Xylem is a vascular and mechanical tissue. In other words it is a conducting tissue. Xylem is composed of four different types. (i) Tracheids (ii) Vessels or Tracheae (iii) Xylem parenchyma (iv) Xylem sclerenchyma.

(b) Phloem:- Phloem contains tubes but performs no mechanical function. Phloem is composed in following four elements or cells (i) Sieve tubes (ii) Companion cells (iii) Phloem parenchyma (iv) Phloem fibres.

(5) (a) The difference between RBCs and WBCs are following:-

Red blood corpuscles are red in color whereas White Blood Cell are colourless.

Size of each RBC is about 7.2 micrometere whereas Size of WBCs varies between 10 to 20 micrometer.

RBC are biconcave rounded in shape whereas, The shape of WBC’s is rounded to amoeboid.

RBC’s cells containing haemoglobin whereas, WBC’s cells containing haemoglobin.

(b) The difference between bone and cartilage are :-

Bone are hard and inflexible whereas, Cartilage are flexible.

Bone are porous whereas Cartilage are non porous.

In Bone, Blood vessels are present whereas , In Cartilage blood vessels are absent.

(c) The difference between Blood and Lymph are following-

(i) Blood is a fluid connective tissue whereas, Lymph is a colorless fluid that is filtered out of the blood capillaries.

(d) Striated muscles are powerful and undergo rapid contraction. These muscles can get tired and may need rest whereas, Unstriated muscles do not work according to our will, so they are also called involuntary muscles.

(e) Tendons are Inelastic whereas, Ligaments are elastic.

Tendons joins muscles to bone whereas, Ligaments connects bones to bone.

(f) Axon is long uniformly thickened fibre like process of a neuron whereas, Dendrite is a short tapering process of a neuron.

Axon is always covered with sheath whereas In Dendrite sheath is absent.

(6) Structure of Epithelium: It is a protective tissue of animal body. The cells of this tissue are tightly packed and they form a continuous sheet. Cells of epithelium contain very little or no intercellular matrix. The tissue covers most organs and cavities within the body. It also forms a barrier to keep different body system separate.

Functions of Epithelium Tissue:-

(i) The cells of the body surface form the outer layer of skin. These cells protect the underlying cells from drying =, injury and chemical effects. They also protect the body from viral or bacterial infection.

(ii) Inside the body, Epithelial cells form lining of mouth and alimentary canal and protect these organs.

(iii) Epithelial tissues help in absorption of water and nutrients.

(7) Connective tissue are classified in 5s, name are:

(i) Loose connective tissue

(ii) Dense Regular connective tissue

(iii) Adipose tissue

(iv) Skeletal tissue

(v) Fluid connective tissue.

(8) Blood is a fluid connective tissue . In this tissue, cells move in a fluid or liquid matrix or a medium called blood plasma.

The blood plasma does not contain protein fibres but contain cells called blood cells. These blood corpuscles or cells are:

(i) RBC (Red Blood Corpuscles)

(ii) WBC (White Blood Cells)

(iii) Platelets.

Functions of Blood: (i) Blood transports nutrients, hormones and vitamins to the tissues and transports excretory products from the tissues to the liver and kidney.

(ii) The Red Blood Corpuscles (RBC) carry oxygen to the tissues for the oxidation of food staff.

(iii) The EBC fight disease either by engulfing and destroying foreign bodies or by producing antitoxins and antibodies that neutralize the harmful effects of germs.

(9) The muscle tissue or muscle of the body form the contractile tissue and are made of muscle cells. Muscle cells are  elongated and large sized so they are also called muscle fibres.

Classification:

(i) Striated muscles

(ii) Smooth Muscles

(iii) Cardiac Muscles

Striated muscles

Striated muscles also known as striped, voluntary, skeletal muscles. Since the entire muscle fibres show alternate dark and light stripes, they are called Striated muscles.

Since they are attached to the bones and are responsible for body movements they are called skeletal muscle.

These muscles work according to our will , they are called voluntary muscle.

Smooth Muscle: Smooth muscles are also known as unstriated, visceral or involuntary muscles.

Smooth muscles occur as bundles or sheets of elongated fusiform or spindle shape cells or fibres. These are held together by loose connective tissue. Each muscle cell is enclosed in a plasma membrane.

Cardiac Muscle: Cardiac muscles show characteristics of both smooth and striated muscles. Cardiac muscles are composed of branched fibres and branches join to form a network.

(10) Neuron has three parts:

(i) The cyton or cell body which contains a central nucleus and cytoplasm which characteristic deeply stained particles called Nissl’s granules.

(ii) The dendrons which are short processes arising from the cyton and further branching into dendrites.

(iii) The axon which is a single, long cylindrical process of uniform diameter. It forms fine branches terminally. Each such twig like branch of axon ends in a swollen structure called synaptic knob or bouton. Bouton contains acetylcholine filled vesicles.


Leave a Reply

Your email address will not be published. Required fields are marked *

17 + one =