Junior TODAY

Class 9 Notes
IS MATTER AROUND US PURE

1. Pure Substance & mixture

PURE SUBSTANCE

• Pure substance consists of a single type of substance .
• Pure substance cannot be separated into other substances by physical methods
• Pure substance has its own definite properties

MIXTURE

• Mixture consists of two or more pure substances.
• Mixture can be separated into its components by physical methods.
• Mixture shows the properties of its components.

Elements

Elements are made up of one kind of atoms only. Compounds are made up of one kind of molecules only.
Difference between Compound &Mixture

[ Refer NCERT text Book Tab.2.2, page 26]
Q.1 Is air around us a compound or mixture?
Q.2 Water is a compound. Justify.
Q.3 Classify the following as element , compound and mixture: Iron , sea water , Milk
Q.4 Are the naturally occurring material in nature chemically pure substances?

2). Types of Mixtures Mixtures can also be grouped

i)On the basis of their physical states:
solid liquid gas
SOLID • Salt and sugar • Salt and water • Dust in air
LIQUID • Mercury and copper • Alcohol and water • Clouds
GAS • Hydrogen and palladium • Oxygen and water • Air

ii) On the basis of miscibility:

Homogeneous Mixture
• It consists of single phase.
• Uniform composition.
• Example: Sugar dissolved in water

Heterogeneous Mixture
• It consists of two or more phase.
• Does not have uniform composition.
• Example: Air, sand and common salt.

Q.1 Give one example for each of the following mixtures:
i) Solid/solid (homogeneous)
ii) Solid/solid (heterogeneous)
iii) Liquid/liquid (homogeneous)
iv)Liquid/liquid (heterogeneous)
v) Gas/liquid (homogeneous)..

Q.2 Classify the following as homogeneous & heterogeneous mixture:
i) sodium chloride & water
ii) glucose & water
iii) sand & water
iv) air

3. Separating the components of a mixture

The components of a heterogeneous mixture can be separated by
1.Simple methods like :-
hand picking , sieving , & Winnowing

2.Special techniques like: -
i) Evaporation : a mixture of salt and water or sugar and water.
ii) Centrifugation : Butter from curd, Fine mud particles suspended in water.
iii) Decantation (Using separating funnel) : Oil from water.
iv) Sublimation : Camphor from salt,
v) Chromatography : Different pigments from an extract of flower petals.
vi) Distillation and fractional distillation : Separating components of Petroleum
vii) Magnetic separation: Iron pins from sand.

Q.1 Name the process you would use to :
i) recover sugar from an aqueous sugar solution.
ii) separate mixture of salt solution and sand.
Q.2 How will you separate a mixture of sand , water and mustard oil ?

4. Concentration of Solution

The amount of solute present in a given amount (mass or volume) of solution.
Concentration of a solution = Amount of solute / amount of solvent
The concentration of a solution can be expressed as mass by mass percentage or as mass by volume percentage.
Mass by mass percentage of a solution = Mass of solute × 100/ Mass of solution
Mass by volume percentage of a solution = Mass of solute ×100/Volume of solution

Types of Solutions

a) on the basis of size of solute particles:

True solution
• Homogeneous
• Size of solute particles is less than 1 n m or 10-9 m .
• Particles cannot pass through filter paper
• Stable
• Solution of sodium chloride in water, sugar & water.

Sol [ Colloid]
• Heterogeneous
• Size of solute particles is between 1 nm to 1000 nm.
• Particles can pass through filter paper.
• Stable and settle only on centrifugation
• Milk , Fog

Suspension
• Heterogeneous
• Size of solute particles is more than 1000 nm.
• Particles cannot pass thorough filter paper.
• Unstable and settle down on its own.
• muddy water, chalk & water,
• smoke in the air.

Colloidal solution is a heterogeneous mixture. It consists of two phases:-

(i) Dispersed phase : component present in small proportion
(ii) Dispersion medium : component present in large proportion

Tyndall effect

The particles of colloid are large enough to scatter a beam of light passing through it and make its path visible. Thus, they show Tyndall effect.

Brownian movement.

The colloidal particles are moving at random in a zigzag motion in all directions. This type
of zig-zag motion of colloidal particles is called Brownian movement.

b) On the basis of amount of solute:

Unsaturated solution
A solution which has lesser amount of solute that it can dissolve at a given temperature is known as unsaturated solution.

Saturated Solution
A solution which has maximum amount of solute that it can dissolve at a given temperature is known as saturated solution.

Supersaturated solution
A solution which can dissolve amount of solute by increasing temperature saturated solution is known as supersaturated solution.

c) On the basis of nature of solvent

Aqueous solution
The solution in which the solvent is water is known as aqueous solution.

Non-Aqueous solution
The solution in which the solvent is other than water (ether, alcohol or aceton) known as non-aqueous solution.

Q.1 Classify the following substances into true solutions and colloidal solutions. Milk , ink , starch dissolved in water.
Q.2 A solution has been prepared by dissolving 5g of urea in 95 g of water. What is the mass percent of urea in the solution?
Q.3 Give an example of an aqueous solution in which gas is dissolved.

5.Physical & Chemical Changes

Physical changes
Changes that do not result in the production of a new substance.
• If you melt a block of ice, you still have H2O at the end of the change.
• If you break a bottle, you still have glass
Examples : melting, freezing, condensing, breaking, crushing, cutting, and bending.
Chemical changes
- Changes that result in the production of another substance.
• As in the case of autumn leaves, a change in color is a clue to indicate a chemical change.
• a half eaten apple that turns brown.

Q.1 Which of the following is an example of physical change?
a. Mixing baking soda and vinegar together, and this causes bubbles and foam.
b. A glass cup falls from the counter and shatters on the ground.
c. Lighting a piece of paper on fire and the paper burns up and leaves ashes.
d. Baking a birthday cake for your mother.
Q.2. Which of the following is an example of chemical change?
a. Filling up a balloon with hot air.
b. Taking a glass of water and freezing it by placing it in the freezer.
c. A plant collecting sunlight and turning it into food.
d. Your dog ripping up your homework.
Q3. Which change can be easily be reversed?
a. Chemical Change
b. Physical Change
c. Both a physical and chemical change
d. Neither a physical or chemical change

6.Alloys

A material that has metallic properties and is composed of two or more chemical elements of which at least one is a metal .
• These cannot be separated into their components by physical methods.
• However, these are considered as mixture because these show the properties of its
constituents and can have variable composition.
The benefit of alloys is that you can combine metals that have varying characteristics to create an end product that is stronger, more flexible, or otherwise desirable to manufacturers.
• Aluminium alloys are extensively used in the production of automotive engine parts.
• Copper alloys have excellent electrical and thermal performance, good corrosion
resistance, high ductility and relatively low cost.
• Stainless steel alloys are used for many commercial applications such as watch
straps, cutlery etc.
• Titanium alloys have high strength, toughness and stiffness & are used in aerospace
structures .

Q,1 Why should we use alloys instead of pure metals?
Q.2 State uses of Aluminium & Stainless steel alloys.

QUESTION BANK

1 Mark Questions:

1. What is meant by pure substance?
2. What is meant by mass percentage of solution?
3. Name the process of separation of miscible liquids.
4. Arrange the following in decreasing order of size of the particles.
True Solution , Suspension , Colloid.
5. *Give an example of an aqueous solution in which gas is dissolved.
6. Name the dispersion medium and dispersed phase in the white material inside an egg.
7. What happens when hot saturated solution is cooled?
8. How would you separate a mixture of chalk and water?
9. *How much water should be added to 15 grams of salt to obtain 15 % salt solution?
10. What type of mixtures are separated by technique of crystallization ?

3.Marks Questions:

1. Classify the following into elements, compounds and mixtures:
a) Sodium b) Soil c) Sugar solution d) Silver e)Tin f) Calcium carbonate
g) Silicon h) Coal i) Air j) Soap k) Methane l) Carbon dioxide m) Blood.
2. Give any two applications of centrifugation.
3. Which of the following is chemical change?
a) Growth of a plant b) Rusting of iron c) Mixing of iron fillings and sand
d) Cooking of food e) Digestion of food f) Freezing of water
g) Burning of a candle.
4. *State the difference between simple distillation & fractional distillation.
5. * A solution contains 40 ml of ethanol mixed with 100 ml of water. Calculate the
concentration in terms of volume by volume percentage of the solution.

5 Marks Questions:

1. *What is meant by Tyndall effect? What is its cause? Illustrate with example.
2. How would you separate the mixture containing sulphur and sand ?
3. What is crystallization? Give its two applications.
4. How are sol, solution and suspension different from each other?
5. How do we obtain coloured components, i.e. dye from Blue/Black ink ?

You are expected to know………
• Types of mixtures.
• Method of Separation of mixtures.
• Types of solutions.
• Concentration terms of solution.
• Physical and Chemical Change.
• Significance of alloys.

Control and Coordination Class 10
Science Notes biology

➣ Coordination-The working together of various organs of the body of an organism in a proper manner to produce appropriate reaction to a stimulus is called coordination.
➣ Stimulus- The changes in the environment to which an organism responds and reacts is called Stimulus
➣ Control & coordination in animals- takes place by (i) Nervous system & (ii) Endocrine system
➣ Nervous system
Stimulus → Receptor organ → Sensory nerve → Brain/Spinal cord
↓ Response ← Effector organ ← Motor nerve
➣ Endocrine system
Stimulus → Endocrine organ → Secrete hormone → Hormone in blood ↓
Response ← Target organ

➣ Parts of the Nervous system –
(i) Brain (ii) Spinal cord (iii) Nerves (Neurons)
➣ A Neuron is the structural & functional unit of Nervous system
➣ Parts of a neuron-
(i) Dendrites (ii) Cell body (iii) Axon
➣ Synapse- Space/junction between two adjacent nerves is called Synapse.
➣ Passing of information takes place –
(i) By Electric impulse (inside the neuron) and
(ii) In the form of chemicals (At synapse)
➣ Reflex action- Spontaneous, involuntary and automatic response to a stimulus to protect us from harmful situations. Eg. On touching a hot object unknowingly we instantly withdraw our hand.
➣ Reflex arc- The pathway of the reflex action is called Reflex arc.
Stimulus → Receptor organ → Sensory nerve → Spinal cord →Effector organ→ Response

Refer to figure 7.2 page no. 117 of N.C.E.R.T Text book)
➣ Nervous system-
(1) Central Nervous system (CNS)
(2) Peripheral Nervous system(PNS)
(i) Brain (i) Autonomic Nervous system
(ii) Spinal cord (ii) Voluntary Nervous system
➣ Brain
(i) Centre of coordination of all activities
(ii) Thinking is involved
(iii) Complex process
➣ Parts of brain-
Refer to figure 7.3 page no. 118 of N.C.E.R.T Text book
Fore brain Mid brain Hind brain
(i) Cerebrum
(ii) Thalamus
(iii) Hypothallamus
---------- (i) Cerebellum
(ii) Pons
(iii) Medulla oblongata
➣ Fore brain Cerebrum-
(i) Main thinking and largest part of the brain.
(ii) It has 3 main areas-
a) Sensory area- to receive impulses from sense organs via Receptors
b ) Motor area- control voluntary movements.
c) Association areas- Reasoning, learning & intelligence.

Thalamus – It relays sensory information to the Cerebrum

Hypothallamus- It forms the link between Nervous system & Endocrine system
➣ Mid brain- It connects Fore brain and Hind brain. Controls reflex of eyes & ears
➣ Hind brain- Connects the Fore brain & Hind brain
Cerebellum – Controls & coordinates muscular movements, maintaining body posture and equilibrium.
Pons- Acts as a bridge between brain & spinal cord
Medulla oblongata- Controls involuntary actions like blood pressure, salivation, vomiting, etc.
➣ Spinal cord- Cylindrical or tubular structure extending downwards from the Medulla oblongata.
➣ Protection of the brain & the spinal cord-
(i) Bony outer covering: skull for the brain & vertebral column for the spinal cord.
(ii) Cerebrospinal fluid present in between the three membranes.
➣ Action caused by Nervous tissue
Information → Nervous tissue → Brain Muscles → Causes action

➣ Path or action-
Nerve impulse → Muscle cell → Changes shape due to special proteins
↓
Action caused ← Shorter form of muscles ← Change shape & arrangement of cell
➣ Chemical communication by hormones- (advantages)
(i) Electrical impulses have their limitations because they reach only those cells connected to the nervous tissue.
(ii) Also the nerve cells cannot generate & transmit impulses continuously.
iii)Electrical communication is slower.
➣ Hormones-
(i) are chemical messengers secreted by endocrine glands
(ii) Are secreted in small amounts & may act in nearby places or distant places.
(iii) Do not take part in the reaction & are destroyed immediately.

➣ Hormones are secreted by- Endocrine glands & Exocrine glands
S. No. Endocrine glands Exocrine glands
1. Ducts absent 1. Ducts present
2. Secrete hormones 2.Secrete enzymes
3. Secreted in blood 3.Secreted in ducts of glands
4. Situated away from the site of action 4.Situated near the site of action

➣ Some glands which act as both endocrine & exocrine

Gland:-

1)Pancreas
Endocrine function - Produces insulin & Glucagon
hormone.
Exocrine function - Produces digestive enzyme. (pancreatic
amylase)

2)Te**es
Endocrine function - Produces hormone Testosterone
Exocrine function - Produces male gametes (reproductive cells)

3)Ovaries
Endocrine function - Produces hormone Oestrogen
Exocrine function - Produces female gametes (reproductive
cells)

➣ Important Endocrine glands, the hormone they secrete & their function

Refer to figure 7.7 page no. 124 of N.C.E.R.T Text book)

1) Pituitary gland - Growth hormone
Function - Body growth, development of bones & muscles
(If excess- Gigantism) (If less- Dwarfism)

2)Thyroid gland - Thyroxine
Function - Regulates carbohydrate, protein & fat
metabolism

3)Pancreas - Produces insulin & Glucagon hormone
Function - Regulates blood sugar levels (if less diabetes is
caused)

3)Te**es in males - Produces hormone Testosterone
Function - Development of secondary male characters like
deep voice, beard, etc.

4)Ovaries in females - Produces hormone Oestrogen
Function - Development of secondary female characters like
mammary glands, menstrual cycle, maintenance of pregnancy.

Endocrine gland Hormone Function
Pituitary gland Growth hormone Body growth, development of bones & muscles
(If excess- Gigantism) (If less- Dwarfism)
Thyroid gland Thyroxine Regulates carbohydrate, protein & fat
metabolism
Pancreas Produces insulin &
Glucagon hormone Regulates blood sugar levels (if less diabetes is
caused)
Te**es in males Produces hormone
Testosterone Development of secondary male characters like
deep voice, beard, etc.
Ovaries in
females Produces hormone
Oestrogen Development of secondary female characters like
mammary glands, menstrual cycle, maintenance of pregnancy.

➣ Coordination in plants- Only chemical coordination is present in plants.

➣ Tropic movements- The movements of plants in the direction of stimulus (positive) or away from it (negative) are called tropic movements. E.g. Phototropism, Geotropism. Chemotropism.

Refer to figure 7.4 & 7.5 page no. 121 of N.C.E.R.T Text book)

➣ Nastic movements -The movements of plants independent of stimuli are called nastic movements. E.g.- Touch me not plant leaves close when touched.

➣ Plant hormones (Phytohormones) Examples-
1. Auxins- Help in growth of root & shoot tips.
2. Gibberellins- Help in vegetative growth
3. Cytokinins- Promote cell division
4. Abscissic acid - Inhibits growth & causes wilting (falling) of leaves
➣ Important diagrams-
1. Structure of neuron (nerve cell)
2.Reflex arc
3.Human brain
4.Endocrine glands .
➣ Important activities-
1. To compare taste of sugar and food with open & blocked nostrils.
2. To demonstrate the response of a plant to the direction of light. 3. To demonstrate hydrotropism

Maths Notes
Surface Areas and Volumes

RIGHT CIRCULAR CYLINDER:

A right circular cylinder is solid generated by the revolution of a rectangle about of its sides.
NOTE : If a paper, cylinder open at both the ends is cut along a vertical line on the curved surface and stretched on a plane surface, we obtain a rectangle of length i.e.,
27πr and breadth= Height of cylinder h.
So, curved surface area (C.S.A) or lateral surface area = 2πr * height
Important Formula For Cylinder

1. C. S. A of cylinder = ( Perimeter of base) * Height = 2πrh
2. Area of each end of cylinder = 2πr2
3. Total surface area (including both circular ends) = 2πrh + 2πr2 = 27πr(h + r)
4. Volume of cylinder — πr2h = [(Area of base) * height]

Hollow Cylinder’s formulae e.g., (Rubber tubes pipes, etc.)

1. Volume of material = Exterior volume — Interior volume = πR2h — πR2h = πh(R2 – r2)
2. C. S. A or L. S. A = external surface area + internal surface area

= 2πRh + 2πrh
3. T. S . A. of hollow cylinder = C. S. A+ 2 ( area of base ring )
= (2πRh + 2πrh) + 2(πR2 – πR2)

NOTE:
1. Two end faces of right circular cylinder are circles having each area = πR2
2. Mass of cylinder = Volume * density
3. When rectangular sheet of paper is rolled along its length , we get a cylinder whose base circumference is length of sheet and height is same as breadth of sheet.

CONE

Important Formula Of rt. Circular Cone :

1. Volume of cone = 1 / 3 πR2h
2. C. S. A or L. S. A=πrl where slant height = l =√ R2 + hR2
3. T. S. A of cone = πrl + πR2
FRUSTUM OF A CONE
FRUSTUM : A cone is cut by a plane parallel to the base of the cone,

Then the portion between the plane and base is called frustum of the cone Important

Formulae for Frustum :

1. Volume of frustum of cone = πh / 3[R2 + R2 + Rr] cubic unit
2. L. S. A or C. S. A = πl(R + r) Sq units where l2 = h2 + (R – r)2
3. T. S. A = πR2 + πR2 + πl(R + r) Sq. units. (Area of base + Area of top + Area of lateral )
4. Slant height (l) = √h22 + (R – r)2

IMPORTANT FORMULA FOR SPHERE AND HEW-SPHERE

(a) Surface area of sphere = 4πR2
(b) Volume of sphere = 4 / 3 πR3
(c) Volume of hemisphere = 2 / 3 πR3
(d) C.S.A. of hemisphere = 2πR2
(e) Total surface area of Hemi-sphere = 2πR2 + πR2 =3πR2

IMPORTANT FORMULA FUR SPHERICAL SHELL/
HEMILSPHERICAL SHELL

(a) Outer surface area of spherical shell =4πR2
(b) Inner S.A. of spherical shell = 4πR2
(c) Total surface area of spherical shell = 4π(R2+ R2)
(d) Volume of spherical shell of external radius R and internal radius ‘r’ = 4 / 3π(R3 – R3)
(e) Outer curved surface area hemispherical shell = 2πR2
(f) Inner curved surface area of hemispherical shell = 2πR2
(g) Thick hemispherical bowl of external and internal radii R and r, Total S.A. = π(3R2+ R2)
(h) Volume of hemispherical shell of external radius ‘R’ and internal radius ‘r’ = 2 / 3π(R3 — R2).

The Human Eye and the Colourful
CLASS 10 NOTES

1. The Human Eye It is a natural optical instrument which is used to see the objects by human beings. It is like a camera which has lens and screen system.

(i) Retina : It is a light sensitive screen inside the eye on which image is formed. It contains rods and cones.

(ii) Cornea : It is a thin membrane which covers the eye ball. It acts like a lens which refracts the light entering the eye.

(iii) Aqueous humour : It is fluid which fills the space between cornea and eye lens.

(iv) Eye lens : It is a Convex lens made of transparent and flexible jelly like material. Its curvature can be adjusted with the help of ciliary muscles.

(v) Pupil : It is a hole in the middle of iris through which light enters the eye. It appears black because light falling on it goes into the eye and does not come back.

(vi) Ciliary muscles : These are the muscles which are attached to eye lens and can modify the shape of eye lens which leads to the variation in focal lengths.

(vii) Iris : It controls the amount of light entering the eye by changing the size of pupil.

(viii) Optical nerve : These are the nerves which take the image to the brain in the form of electrical signals.

2. Accomodation power : The ability of eye to change the focal length of eye lens with the help of ciliary muscles to get the clear view of nearby objects (about 25 cm) and far distant objects (at infinity).

3. Colour blindness : Some people do not possess some cone cells that respond to certain specific colours due to genetic disorder.

4. Myopia (Short sightedness) : It is a kind of defect in human eye due to which a person can see near objects clearly but he can not see the distant objects clearly. Myopia is due to

(i) excessive curvature of cornea.
(ii) elongation of eye ball.

5. Hypermetropia (Long sightedness) : It is a kind of defect in human eye due to which a person can see distant objects properly but cannot see the nearby objects clearly. It happens due to

(i) decrease in power of eye lens i.e., increase in focal length of eye lens.
(ii) shortening of eye ball.

6. Presbyopia : It is a kind of defect in human eye which occurs due to ageing. It happens due to

(i) decrease in flexibility of eye lens.
(ii) gradual weakening of cilliary muscles.

7. Astigmatism : It is a kind of defect in human eye due to which a person cannot see (focus) simultaneously horizontal and vertical lines both.

8. Cataract : Due to the membrane growth over eye lens, the eye lens becomes hazy or even opaque. This leads to decrease or loss of vision. The problem is called cataract. It can be corrected only by surgery.

9. Dispersion of white light by a glass prism : The phenomenon of splitting of white light into its seven constituent colours when it passes through a glass prism is called dispersion of white light. The various colours seen are Violet, Indigo, Blue, Green, Yellow, Orange and Red. The sequence of colours remember as VIBGYOR. The band of seven colours is called spectrum.

10. Composition of white light : White light consists of seven colours i.e., violet, indigo, blue, green, yellow, orange and red.

11. Monochromatic light: Light consisting of single colour or wavelength is called monochromatic light, e.g., sodium light

12. Polychromatic light : Light consisting of more than two colours or wavelengths is called polychromatic light, e.g. white light.

13. Recombination of white light : Newton found that when an inverted prism be placed in the path of dispersed light then after passing through prism, they recombine to form white light.

14. Formation of rainbow : The water droplets act like small prisms. They refract and disperse the incident sunlight, then reflect it internally, and finally refract it again when it comes out of the raindrop. Due to the dispersion of light and internal reflection, different colours reach the observer’s eye.

15. Atmospheric Refraction : The refraction of light caused by the earth’s atmosphere (having air layers of varying optical densities) is called atmospheric refraction.

16. Why, the duration of day becomes approximately 4 minutes shorter if there is no atmosphere on earth : Actual sun rise happens when it is below

Science Class 9 Notes
TISSUES
1. Tissue is a group of cells having similar origin, structure& function. Study of tissues is called Histology

2. In unicellular organism (Amoeba) single cell performs all basic functions, whereas in multi-cellular organisms (Plants and Animals) shows division of labor as Plant tissue & Animal tissues.

3. Plant tissues are two types: Meristems & Permanent tissues.

4. Meristems: The Meristems are the tissues having the power of cell division. It is found on those region of the plant which grows.

5. Types of Meristems;

1. The Apical meristems – It is present at the growing tip of the stem and roots and increases the length.

2. The lateral meristems - present at the lateral side of stem anf root (cambium) and increases the girth.

3. The intercalary meristems - present at internodes or base of the leaves and increases the length between the nodes.

( Please refer to Fig. 6.2: location of meristems in plant body , NCERT Book Page- 69).

26. Permanent tissues: Two types such as Simple permanent tissues & Complex permanent tissues.

a) Simple permanent tissues: subdivided as
(i): Parenchyma: Tissues provide the support to plants.They are loosly packed and has large intracellular space.

- Parenchyma with chlorophyll which performs photosynthesis is called as chlorenchyma.

- The parenchyma with large air spaces to give buoyancy is called as aerenchyma .Parenchyma also stores food and water.

(ii) Collenchyma: Tissue provides mechanical support, thickened at the corners, have very little intercellular space. It allows easy bending of various parts of a plants without breaking

(iii) Sclerenchyma: Tissue makes the plant hard and stiff, thickened due to lignin and no intercellular space. Cells of this tissue are dead and commonly seen in the husk of coconut.

(iv) Guard cells& Epidermal tissue: the tissue aids in protection and exchange of gases. Guard cells kidney shaped in dicots, dumb bell shaped in monocots to guard the stomata. The epidermal tissues of roots aid in absorption of water and minerals. The epidermal tissues in desert plants have a thick waxy coating of Cutin with waterproof quality. The epidermal tissues form the several layer thick Cork or the Bark of the tree.

(Please refer to Fig. 6.3- 6.6, NCERT Book Page-70-73).

b) Complex permanent tissues: The complex tissues are made of more than one type of cells. All these cells coordinate to perform a common function. They are subdivided as;

Xylem: It consists of tracheids, vessels, xylem parenchyma and xylem fibers. The cells have thick walls,

Function - aids in conduction of water and minerals.

Phloem: It consists of sieve tubes, companion cells, phloem parenchyma, and phloem fibers.

Function - Phloem transports food material to other parts of the plants.

(Please refer to Fig. 6.7, NCERT Book Page-73).
6. Animal tissues: Sub divided as epithelial tissue, connective tissue, muscular tissue and nervous tissue.

i. Epithelial tissue: It is a protective covering forming a continuous sheet. Simple epithelium is the one which is extremely thin in one layer, whereas stratified epithelium are arranged in pattern of layers.

Depending on shape and function they are classified as:

a) Squamous epithelium in the lining of mouth and esophagus.

b) Cuboidal epithelium in the lining of kidney tubules and salivary glands.

c) Columnar epithelium in the intestine &Columnar epithelium with cilia in the lining of respiratory tract.

d) Glandular epithelium in the Glands aids in a special function as gland cells, which can secrete at the epithelial surface.

(Please refer to Fig. 6.9, NCERT Book Page-75).

ii) Connective Tissue: Five Types, such as;

a) Blood: The Blood is a fluid connective tissue. Blood plasma has RBCs (Red Blood Cells) WBCs (White Blood Cells) and platelets. Blood plasma contains proteins, salts and hormones. Blood flows and transports gases, digested food, hormones and waste materials.

b) Bone: The bone is a connective tissue with hard matrix, composed of calcium and phosphorus. A bone is connected by another bone with another connective tissue called ligaments. A bone is connected by muscle with another connective tissue called tendon.

c) Cartilage: The cartilage is a connective tissue with solid matrix composed of proteins and sugars. It is commonly seen in nose, ear, trachea, and larynx.

d) Areolar Connective Tissue: It is found between the skin and muscles, around the blood vessels. It supports internal organs and aids in repair of tissues.

e))Adipose Connective Tissue: It is filled with fat globules for the storage of fat. It acts as insulator.
(Please refer to Fig. 6.10, NCERT Book Page-76).
Muscular tissues: They have special contractile proteins responsible for movements. Three types, such as;

Striated muscles/skeletal muscles/voluntary muscles :

They are cylindrical, un-branched and multinucleated.They have dark bands and light bands.

Unstriated muscles/smooth muscles/involuntary muscles:

They are commonly called as Smooth muscles, having no striations (dark bands/ light bands are absent). Commonly found alimentary canal, uterus, Iris of an Eye. They are spindle shaped. Involuntary in nature

Cardiac Muscles: They are commonly called as Heart muscles, cylindrical, 68 branched and uni-nucleate. Involuntary in nature.

(Please refer to Fig. 6.11, NCERT Book Page-77).

Nervous Tissue: The tissue responds to stimuli. The brain, spinal cord and nerves are composed of nervous tissue or neurons. A neuron consists of Cell Body, cytoplasm, Nucleus, Dendrite, Axon, nerve ending. The neuron impulse allow us to move our muscles when we want to respond to stimuli. (Please refer to Fig. 6.12, NCERT Book Page-78).
QUESTION BANK

1. Define the term tissue……………. ( A group of cells forms tissue)
2. What is Histology? ( Study of different tissues)
3. How many types of meristems are present in plants? (3 : Apical meristems, Lateral meristem, Intercalary meristem )
4. Name the Parenchyma with chlorophyll which performs photosynthesis………………… (chlorenchyma)
5. Which plant tissue makes the plant hard and stiff and thickened due to lignin with no intercellular spaces …………………….(Sclerenchyma)
6. Give the details of epidermal tissue in Plants. (For protection and exchange of gases. Guard cells kidney shaped in dicots, dumb bell shaped in monocots to guard the stomata. The epidermal tissues of roots aid in absorption of water and minerals.)
7. Which elements constitute the Phloem? (Sieve tubes, companion cells, phloem parenchyma, and phloem fibers.)
8. Distinguish between ligament and tendon (A bone to bone connective tissue called ligament. A bone to muscle connective tissue called tendon.)
9. Name the three muscular tissues in the animals……..(Striated muscles ,Un- Striated muscles, Cardiac Muscles)
10. Draw the neuron and label it (Please refer to Fig. 6.12, NCERT Book Page-78).
QUESTION PAPER: FORMATIVE ASSESSMENT – I (For Practice)
1. Questions 1-5 (1 Mark each) 2. Questions 6-10 ( 2 Mark each)
3. Questions 11-15 (3Mark each) 4. . Questions 16-17 (5Mark each)

Q.1 What is a group of cells that are similar in structure and work called?
Q.2 Which is the hardest connective tissue?
Q.3 What is the name of Blood matrix?
Q.4 By what process permanent tissues are formed?
Q.5 Two bones are connected with ligaments. Mention True/ False…………….
Q.6 What are the two main types of tissues found in plants? Q.7 Draw the structure of Stomata and label it.
Q.8 Write the main functions of parenchyma
Q.9 What are the fluid connective tissues?
Q.10 What is the difference between voluntary and involuntary muscles?
Q.11 Write a short notes on Cardiac muscles.
Q.12 Draw a labeled diagram of areolar tissue.
Q.13 Mention the three elements of Xylem tissue.
Q.14. Write a short notes on Glandular Epithelium.
Q.15. Write three significant points about Sclerenchyma
Q.16 With the help of suitable diagram, describe the Phloem.
Q.17 Draw and label the Nerve Cell.Explain in brief.