Tissues
Exercises
Section I
A. Name the following.
1. Tissues made up cells that do not have the ability to divide.
= Permanent tissues;
2. A type of parenchyma that contains chloroplasts and is found in leaves.
= Chlorenchyma;
3. Sclerenchyma cells found in seed coats and pulp of fruits.
= Sclereids;
4. A type of connective tissue that connects muscles to bones.
= Tendons;
5. They type of muscle that is made of spindle-shaped cells.
= Unstriated muscles;
6. The cell body of a nerve cell.
= Cyton;
7. Animal tissues that are hard and have deposits of minerals.
= Supportive Connective tissues;
8. A fluid connective tissue.
= Blood;
B. Choose the correct option.
1. This simple tissue in plants is made up of dead cells.
a. Parenchyma. [ ]
b. Collenchyma. [ ]
c. Chlorenchyma. [ ]
d. Sclerenchyma. [✓]
2. Which of the following is a lateral meristem?
a. Tracheids. [ ]
b. Sieve tubes. [ ]
c. Cambium. [✓]
d. Companion cells. [ ]
3. Cotton fibres are a type of ………..
a. collenchyma. [ ]
b. sclerenchyma. [✓]
c. parenchyma. [ ]
d. meristems. [ ]
4. This tissue is found in between vertebrae.
a. Ligament. [ ]
b. Tendon. [ ]
c. Areolar tissue. [ ]
d. Cartilage. [✓]
5. Striated muscles have …..….. nuclei.
a. one. [ ]
b. two. [ ]
c. three. [ ]
d. many. [✓]
C. Write True or False. Correct the false statements by changing the first or last word(s).
1. Chitin is the waxy coating secreted by leaf epidermis. [F]
= Cuticle is the waxy coating secreted by leaf epidermis.
2. Collenchyma and sclerenchyma are complex tissues. [F]
= Collenchyma and sclerenchyma are simple tissues.
3. Tendons connect one bone to another at the joints. [F]
= Ligaments connect one bone to another at the joints.
4. The fluid matrix in blood is called plasma. [T]
5. Unstriated muscles have branched cells. [F]
= Cardiac muscles have branched cells.
6. Bundles of axons together form a neuron. [F]
= Bundles of axons together form a nerve.
D. State the main functions of the following.
1. Lateral meristem.
= They bring about an increase in the girth and thickness of stems and roots.
2. Parenchyma.
= The main function of this tissue is to synthesize and store food.
3. Phloem.
= The main function of phloem is to transport dissolved food substances from the leaves both upwards and downwards throughout the plant.
4. Epithelial tissue.
= Epithelial tissue covers the external body surface, such as skin, and also forms a continuous lining of body cavities, in many internal organs, such as bronchioles and stomach.
5. Ligament.
= They connect one bone to another at the joints, holding them together in position, so that bones remain stable during movement.
E. Choose the odd term in each of the following sets and write down the category to which the other three belong. Example: petal, stamen, root, pistil; Answer: odd term - root; category - parts of a flower.
1. Parenchyma, collenchyma, phloem, sclerenchyma.
= Odd term - Phloem;
Category - Types of simple tissue.
2. Sieve tube, companion cell, tracheid, collenchyma.
= Odd term - Collenchyma;
Category - Types of complex tissue.
3. Bone, ligament, neuron, cartilage.
= Odd term - Neuron;
Category - Types of Connective tissues.
4. Epithelial tissue, meristematic tissue, connective tissue, nervous tissue.
= Odd term - Meristematic tissue;
Category - Types of Animal tissues.
5. Apical, lateral, muscular, intercalary.
= Odd term - Muscular;
Category - Types of Plant tissues.
F. Match the following.
=
|
Column A |
Column B |
|---|---|
|
1.Meristematic tissue |
a. collenchyma. [ ] |
|
2. Complex tissue |
b. cardiac. [4] |
|
3. Supportive connective tissue |
c. cambium. [1] |
|
4. Muscular tissue |
d. blood. [5] |
|
5. Fluid connective tissue |
e. cartilage. [3] |
|
|
f. parenchyma. [ ] |
|
|
g. phloem. [2] |
Section II
G. Give reason for the following.
1. Permanent tissues do not divide.
= Permanent tissues do not divide because they are composed of a group of cells, which have lost the power to divide.
2. Chlorenchyma cells can make food.
= Chlorenchyma cells can make food because it contains chloroplast.
3. Bones are hard and strong.
= Bones are hard and strong because inorganic salt of calcium, magnesium, and phosphorus are present in the bone matrix that make bones strong and rigid.
4. Blood is a fluid connective tissue.
= Blood is a fluid connective tissue because it carries oxygen and nutrients to different tissues and cells of the body.
5. Cardiac muscles work tirelessly.
= Cardiac muscles work tirelessly because these muscles are involuntary muscles.
H. Differentiate between the following pair of words based on what is given in the bracket.
1. Meristematic and permanent tissue. (definition)
= Meristematic tissues have the ability to undergo repeated divisions to form new cells. But permanent tissues are made up of cell, which do not have the ability to divide.
2. Parenchyma and collenchyma. (cell wall)
= Parenchyma has thin cell wall but collenchyma has thick cell wall.
3. Xylem and phloem. (material transport)
= Xylem transports water and minerals upwards from roots to leaves. But phloem transports prepared food from leaves.
4. Ligament and tendon. (location)
= Ligament is located at the bone joints but tendon is located at the end of skeletal muscles.
5. Striated and unstriated muscles. (shape of their constituent cells.)
= Striated muscles are made up of long and cylindrical cells but unstriated muscles are made up of spindle-shaped cells.
I. Define the following terms.
1. Complex tissues.
= Complex tissues are made up of two or more different kinds of cells that work together as a unit.
2. Aerenchyma.
= Aerenchyma is a type of parenchymatous tissue that has large air cavities in it. It is present in aquatic plants and helps them to float.
3. Blood.
= It is a red-coloured fluid that flows through the blood vessels within our body. It carries oxygen and nutrients to different tissues and cells of the body. It also collects metabolic wastes from all body cells for excretion.
4. Cartilage.
= It is relatively softer and more flexible than a bone and does not have blood supply. Cartilage is found at the end of bones, in between vertebrae, around the trachea, and forms the structural part of organs, such as ear, nose, epiglottis, and ribcage.
5. Epithelial tissue.
= Epithelial tissues are made up of closely packed cells with no intercellular spaces. Epithelial tissues can be present in a single layer or in multiple layers of cells throughout the body. Epithelial tissue covers the external body surface, such as skin, and also forms a continuous lining of body cavities.
J. Short answer questions.
1. What are the functions of meristematic tissues?
= These tissues provide new cells that differentiate into specialized tissues for the development of new organs. They help to bring about growth in length of plants and increase in the thickness of stems and roots.
2. Why are xylem and phloem are called conducting tissues?
= Xylem and phloem are found together; hence, they are collectively called conducting tissue or vascular tissues.
3. Where are fibres and sclereids found in plants?
= Cells of sclerenchyma are of two types: Fibres and sclereids.
Cells of fibres are elongated with pointed ends. They have simple pits in their walls.
Cells of sclereids are small, oval, or irregular in shape and possess extremely thick, lignified walls with pits.
4. What is the composition of blood?
= Blood is made up of a straw-coloured fluid matrix called plasma, which contains about 90% water. It is the major component of blood. Blood also contains blood cells, dissolved salts and proteins.
Three different types of blood cells are suspended in the plasma: white blood cells, red blood cells and platelets.
5. How are cardiac muscles structurally similar to striated muscles?
= Both cardiac and striated muscles are cylindrical in shape.
K. Long answer questions.
1. What are the characteristic features of meristematic tissues?
= Meristematic tissues have the following characteristic features -
i. They have closely packed cells with little or no intercellular spaces between them.
ii. The cells are more or less alike in shape, being either spherical, oval, or polygonal.
iii. They are made up of living cells.
iv. Each cell contains a dense protoplasm, with a thin cell wall, and a large centrally located nucleus. Vacuoles are either very small or absent.
2. Write the location and function of the three type of simple permanent tissues found in plants.
=
|
Tissue |
Location |
Function |
|---|---|---|
|
Parenchyma |
All organs of plants mainly comprising ground tissue. |
Photosynthesis, food storage, keeps aquatic plant float. |
|
Collenchyma |
Beneath stem epidermis, in leaf stalk. |
Mechanical strength to plants, flexibility to leaf and stem. |
|
Sclerenchyma |
Outer cortex, midrib of leaves, xylem, and phloem. |
Mechanical strength to plants. |
3. What are permanent tissues? Draw a mind map of types of permanent tissues.
= Permanent tissues are made up of cells, which do not have the ability to divide.
Simple permanent tissues are made up of similar looking cells. The epidermis (outermost covering of young parts of plants) is a dermal tissue. Ground tissues make up the bulk of plant body. They are of three types : parenchyma, collenchyma and sclerenchyma.
Complex permanent tissues are made up of two of more different kinds of cells. Xylem and phloem are complex tissues. Xylem conduct water and dissolved mineral salts upwards from the roots to leaves. Phloem carry dissolved food substances from leaves to different parts of the plant.
Mind map of types of permanent tissues
4. Describe the different constitutes of the blood.
= Blood is made up of a straw-coloured fluid matrix called plasma, which contains about 90% water. It is the major component of blood. Blood also contains blood cells, dissolved salts and proteins.
Three different types of blood cells are suspended in the plasma: white blood cells, red blood cells and platelets.
The red blood cells (erythrocytes) contain a red pigment called haemoglobin that carries oxygen to the different parts of the body. White blood cells (leucocytes) protect up from disease-causing micro organisms and so defend our body against infections. Platelets (thrombocytes) initiate the process of blood clotting. They prevent further bleeding in case of injury.
5. Explain the structure of a nerve cells with the help of a diagram.
= Nerve cells are called neurons. A neuron consists of a cell body, dendrites and an axon.
Cell Body : It is also called cyton. It consists of a mass of cytoplasm enclosed by a plasma membrane and has a central nucleus.
Dendrites : These are structures that branch out from the cyton in a root-like fashion. The function of dendrites is to receive signals from the axon terminals of other nerve cells.
Axon : It is a thin, elongated structure that extends away from the cyton. The axon is capable of sending electric signals over short and long distances from the cell body to the axon terminal. myelin sheath forms an insulating covering around the axon and allows transmission of impulses efficiently.
Bundles of axon together form a nerve.
Picture Study
1.
a. Identify the type of tissue shown in figures 1-3.
= 1 - Striated muscles;
2 - Cardiac muscles;
3 - Unstriated muscles;
b. Give one features of each type of tissues in the figures.
= Tissue 1 (Striated muscle) - They are made up of long and cylindrical cells with many nuclei.
Tissue 2 (Cardiac muscle) - They are capable of rhythmic contraction and relaxation.
Tissue 3 (Unstriated muscle) - They are made up of spindle-shaped cells with a nucleus located at the centre.
c. Which of these are exclusively present in the heart?
= Cardiac muscles (Tissue 2) are exclusively present in the heart.
d. Which of these allow movements according to our will?
= Tissue 1 (Striated muscles) allow movements according to our will.
e. State one structural and one functional difference between 1 and 3.
=
|
Topic |
Tissue 1 (Striated muscles) |
Tissue 2 (Unstriated muscles) |
|---|---|---|
|
Structure |
They are made up of long and cylindrical cells. |
They are made up of spindle-shaped cells. |
|
Function |
They help in the movement of arms and legs. |
They help in the movement of the walls of the digestive tract,
urinary blabber, and other internal organs. |
2.
a. Identify the tissues in 1 and 2. Are they meristematic or permanent tissues?
= Figure 1 - Parenchyma; Figure 2 - Sclerenchyma;
They are permanent tissues.
b. Label the parts marked as 1, 2, and 3.
= 1 - Intercellular space;
2 - Lignified thick walls;
3 - Simple pit;
c. Mention one difference between tissue 1 and tissue 2.
= Tissue 1 (Parenchyma) has intercellular space.
On the other hand, tissue 2 (Sclerenchyma) does not have intercellular space.
d. Give one important function of each of the two tissues.
= The function of tissue 1 (Parenchyma) is to execute photosynthesis, food storage and it keeps aquatic plants afloat.
The function of tissue 2 (Sclerenchyma) is to give mechanical strength to plants.
3.
a. Name the tissues in figure 1 and 2.
= Figure 1 - Xylem; Figure 2 - Phloem;
b. Which of the following categories of plant tissues do they belong?
i. Meristematic or Permanent tissues. [ ]
ii. Simple or Complex tissues. [✓]
=They are complex tissues.
iii. Photosynthetic or Conducting tissues. [ ]
c. Give any two structural differences between 1 and 2.
=
|
Xylem (Figure 1) |
Phloem (Figure 2) |
|---|---|
|
They have tubular or elongated cells. |
They have narrow tubular cells. |
|
They have thick, lignified walls. |
They have thin walls. |
4. Complete the following flowchart on plant tissues.
=
