Daily Archives: March 10, 2022

Flower is the most beautiful and attractive part of a plant. These are available
in different shapes, sizes and colours. It is the reproductive part of a plant. It
produces fruits and seeds.
Structure of a flower –
The flower arises from the floral bud on the stem. It is attached on the axis by
a structure called pedicel. The pedicel continuous to form slightly swollen tip
called thalamus. It bears four consecutive whorls of flower. These are –

1. Calyx – It is the outermost whorl of a flower. It consists of green
   coloured leaf-like structures called sepals. The sepal protects the flower
   during bad stages.
2. Corolla – It is the second whorl of a flower. It consists of large, brightlycoloured, scented petals. Petals enclosed and protect the reproductive
   part of a flower. Corolla attracts insects like bees and butterflies for
   pollination.
3. Androecium – It is the third whorl of a flower. It forms the male
   reproductive part of a flower and consists of many male reproductive
   units. These units are called stamens. The stamen consists of the
   filament and the anther.
   i. Filament – It is a long, thin, hair-like structure which bears
   yellowish sac like structures on its free end.
   ii. Anther – An anther is a small, sac-like structure borne at the tip of
   the filament. Each anther contains many fine, powdery particles
   called pollen grains. Pollen grains play important role in plant
   reproduction as they contain male reproductive cells.
4. Gynoecium – it is the forth whorl of a flower. It constitutes the female
   reproductive part which is known as pistil. Pistil consists of carpels
   (female reproductive units). Each carpel consists of three parts –
   i. Ovary – it contains one or more ovules
   ii. Style – long, tube-like extension of the ovary
   iii. Stigma – pollen grains are received here.
   

1. Complete flower – A flower that shows all the four whorls. Example –
   hibiscus and rose
2. Incomplete flower – a flower that lacks of one or more such
   structures. Example – begonia and willow
   Functions of a flower –

• Primary function is reproduction by producing fruits that contains seeds.
  Seeds help in multiplication of species.
  Pollination –
  The process which involves transfer of pollen grains from the anther to the
  stigma of same or another flower.
  Kinds of pollination –

1. Self pollination –When pollen grains transfer from anther to stigma of
   same flower or flowers of the same plant.
2. Cross pollination – When pollen grains from anther of a flower are
   transferred to the stigma of another flower or another plant of same
   species.
   Agents of pollination –
3. Pollination by insects
4. Pollination by animals
5. Pollination by wind
6. Pollination by water
   Fertilization – The fusion of male and female gametes is called fertilization.
   The Fruit – After fertilization the ovules grows to become seeds. A seed
   contains embryo and food for developing new plants. It has a tough
   protective coating called seed coat. The ovary of a flower can produce
   number of seeds.
   After the process of fertilization, an ovary develops and becomes a fruit.
   When fruit is ripened, other parts of a flower dry up ad fall off. A fruit
   protects the seed.
   

Structure of a fruit – A fruits is made up of two parts.

1. Pericarp – it develops from ovary wall. It further consists of three parts
   i. Epicarp – It is thin, leathery part and is generally discarded.
   ii. Mesocarp – Fleshy, sweet edible part.
   iii. Endocarp – innermost hard layer which encloses the seed
2. Seed – it develops from ovule.
   Types of fruits –
3. Dry fruits – whose pericarp is not distinguished. Example – nut, wheat
   and legumes
4. Fleshy fruits – whose pericarp is distinguished into three parts. Example
   – kiwi and cherry
   Functions of fruits
    It protects the seed from extreme hot or cold weather conditions and
   animals.
    It is an important source of food for animals.
   The Seed – The number and shape of seeds are different in different fruits.
   Structure of Seed –
5. Seed coat – outer protective covering of seed
6. Cotyledon – the fleshy part of the seed. It also stores food for
   developing embryo
7. Embryo – It has two parts
   i. Plumule – it develops into shoot
   ii. Radicle – it develops into root
   Types of seeds – According to numbers of cotyledons, seeds are of two
   types.
8. Monocotyledonous seed –contains only one cotyledons like wheat,
   bajra
9. Dicotyledonous seed – contains two cotyledons like mango, gram etc.
   

Germination of seeds – The process in which a seeds begins to grow.
Types of Germination –

1. Epigeal germination – the hypocotyl elongates rapidly and arches
   upwards pulling the cotyledons which move above the soil. This can be
   seen in dicotyledonous seeds. Example – bean, cotton etc.
2. Hypogeal germination – the epicotyl elongates and the cotyledons
   remain below the soil. It can be seen in monocotyledonous seeds.
   Example – pea, mango etc.
   Conditions necessary for germination – Water, air and suitable
   temperature are essential for seed germination. In the presence of these
   conditions the food stored inside the seed dissolves and provides energy
   to the growing embryo.

Adaptation is the ability of plant and animal to cope means to live and survive with the
conditions of their habitats.
Adaptation can be physical feature or special behaviour.
On basis of habitats organisms divided into five main groups:
o Terrestrial
o Aquatic
o Amphibians
o Arboreal
o Aerial
Adaptation of plants animals with respect to their habitats.
(A) Structural adaptation:
The special body parts of an organism helps in survive.
Change in skin colour, shape are examples of structural adaptation
(B) Physiological adaptation:
The special system found in organism which helps in survival. Ability to maintain a constant
body temperature, making venom comes under physiological changes
(C) Behavioural adaptation:
Taking a certain posture, being active at night are behaviour adaptations.
Aquatic Habitat:
Hydrophytes are the plants found in fresh water bodies.
 As they are light in weight and spongy, and having air chambers make them float in
water. Poor development of root system.Eg. water lily
 Some plants are submerged in water, as they have narrow leaves, lack in stomata as
they breathe to their surface and makes the water clean Eg. Tapegrass
 With developed root system plants termed as fixed plants such as lotus.
Adaptation in Fish:

1. Fish have streamline and smooth body having gills for respiration. Whereas dolphins
   and whale do possess the blowholes at upper parts of their head by which they
   perform breathing above water surface.
2. Presence of scales on their bodies protect them and make easy to swim.
3. Flat fins and tails help the fish to change their direction in water.
4. In salty water as well as in fresh water fish can survive.
   

Adaptation for Deserts:
 Plant Life:

1. Xerophytes are the plants which live in hot and dry climates of deserts.
   Example: cactus, babul.
2. Roots are long to penetrate deep into soil in search of water easily.
   Adaptation in Cactus:
    For storage of water cactus possess fleshy and swollen stem
    The stem is green to store food. Waxy coat help in retention of water.
    Photosynthesis is carried out by leaves
    Leaves are converted into spikes as to reduce loss of water from transpiration.
   Animal Life:
   Animals have fewer pores and thick skin and they excrete less urine and minimal amount of
   sweat in order to retain more water.
   Adaptation in Camel:
3. Have long eyelashes and ear hairs , theses variation protect eyes and ears from sand
   .
4. Long legs to stay away from heat
5. Hump on camel store fat as stored food.
6. Broad feet helps them to walk on sand
7. Ability to drink large amount of water at a time
8. Nostrils can be closed to keep out sand
   Adaptation for Mountains:
   Plant life:
9. Plants grow near the land, which prevent uprooting due to harsh and strong wind.
   Examples pine and fir.
10. Plant cope up with extreme cold temperature.
11. Leaves are needle shaped to prevent water loss
12. Some plants grow under snow layer.
    Animal life:
    Animal mainly found in mountain region are goat, sheep snow leopards, polar bear.
    They have thick coat of hair from prevention of chilling cold.
13. White thick and long fur that keeps the body warm found in case of goat
14. Strong hooves to walk on cliff and on uneven slope.
15. They can jump very far

Adaptation for Air:

Adaptation for flight in Birds

1. Feathers are provide insulation.
2. Feathers protect them from cold and rain and keep the body warm as well
3. Feather are act as water proofing with reflection of UV rays as well
4. Body is light weighted and in streamline to overcome resistance
   Plant Life:
   Aerial plant have root system above ground.
5. Plants evolved with aerial root system in order to absorb more sunlight as in
   evergreen rain forest lack in direct fall of sunlight on ground
6. They may grow on the trunks, leave and branches of host plant.
7. Epiphytes are orchids and bromeliads
8. Epiphytes absorbs moisture from air or moisture laden pockets of the host plant.
9. They are autotrophic in nature.
   Acclimatization:
   This includes the certain changes occur in organism for shorter period of time to help them
   to adjust with periodic changes.
   Example include the growth of thick wool during winter season only in case of sheep.
   o Adaptation refers to the changes in organism for longer period of time
   o Acclimation refers to the changes occur in an organism a short period of time.

There are different types of plants in our surroundings. They are of different sizes varying
from microscopic forms to complex tall trees. They are different in shape, size and colour of
flowers. Some common features seen in all plants are root, stem and leaf.
We know that a plant mainly consist of two systems –

1. Root system – It is the underground part of the plant which develops from the
   radicle body. Radicle is the embryonic root contained in the seed of the plant. Roots
   grow towards the ground and absorb water and minerals from the soil.
2. Shoot System – It consists of a stem, the part which is above the ground. It bears
   braches, leaves, flowers, buds, and fruits.
   LEAF – It is thin, flat and green part of the shoot system.
   It is also known as food factory of a plant.
   It arises from nodes of stem and grows up to a certain size.
   External Structure of a leaf – The leaf constitutes of following parts –
3. Lea Lamina – The green, flat and expanded part of the leaf is known as leaf lamina or
   leaf blade. The tip of lamina is called apex.
4. Leaf Stalk (Petiole) – The basal by which the leaf is attached to the node of stem is
   called petiole.
5. Midrib – The petiole enters the lamina forming the midrib. The midrib branches out
   to form veins which bear branches to form veinlets. Vein provides supportive
   framework to the leaves

Functions of leaf –

1. The primary function is to perform photosynthesis which means to prepare food
   with the help of carbon dioxide and water in the presence of sunlight and
   chlorophyll.
2. It also helps in transpiration i.e. loss of water through stomata.
   

3. It also stores food like in spinach.
4. Leaves give rise to new plants like in Bryophyllum.
5. Leaves get modified into spines in desert plants which help the plant to reduce water
   loss by transpiration.
   Kinds of leaves –
   There is a variety of leaves around us. They can be rectangular, circular, needle-shaped,
   tapered in shape. They may differ in terms of leaf margin which may be complete
   (Peepal), toothed (rose), wavy (mango), spinous (prickly poppy). These leaves can be
   classified into two categories.
6. Simple leaf – In this type of leaf lamina of leaf has a single blade without cuts or
   incisions. If present, do not reach the midrib. Example – mango, radish etc.
7. Compound leaf – In this type of leaf lamina has divided into a number of leaflets. In
   this, the margin has incisions which reach down to the midrib leading to formation of
   small leaflets. Therefore, the leaf appears as a group of leaflets. Example – rose and
   neem.
   To differentiate between leaf and leaflet, we must locate the axillary bud. It is always
   present at the base of the leaf petiole but not at the base of laflet.
   Types of venation –
   The fine lines running through within the lamina forming different patterns are called
   veins. Veins distribute water and minerals to various parts of leaf blade.
   The arrangement of veins and their veinlets within a leaf bade is called venation. There
   are two types of venation.
8. Parallel venation – In this type of venation, the veins run parallel to each other and
   join the midrib. This type of venation can be seen in the leaves of monocotyledonous
   plants like maize, rice and sugarcane etc.
9. Reticulate venation – In reticulate venation, the veins divide and redivide into a
   number of veinlets. This pattern can be observed in the leaves of dicotyledonous
   plants such as mango and peepal.
   Arrangement of leaves – The arrangement of leaves on branches or stem is called
   phyllotaxy. This prevents the leaves from overlapping so that every leaf may get
   sufficient sunlight. There are three types of leaf arrangements.
10. Alternate – In this arrangement, only one leaf is arises from at a node. The next
    arising on the following node is opposite to the previous. Example – mustard and
    sunflower.
11. Opposite – In this arrangement, two leaves are arranged one node but these are
    opposite to each other. Example – jasmine and guava. But in some plants, leaves
    show opposite arrangement with each pair of leaves arising at right angle to each
    other. Example – calotropis.
12. Whorled – In this arrangement, three or more leaves arise from a node and form
    a whorl around it. Example – oleander.
    

Modification in leaves – It means a structural change is required to perform specific
functions. Some of the modifications are –

1. Leaf tendrils – The modification of leaves in thin thread-like coiled strand is called
   leaf tendrils. They are sensitive to touch. They coil around a support in order to
   give support to weaker stems. Thus, help in climbing.
2. Leaf spines – The modification of leaved of desert plant into pointed spines, it is
   called leaf spines. They help to reduce water loss. They also perform defensive
   role as they keep away grazing animals.
3. Scale leaves – In this leaves get modified into scale leaves. They help to protect
   buds. They also store food and water. They may be dry (garlic) or fleshy (onion).
   Modification of leaves in insectivorous plants –
   Insectivorous plants are also known as carnivorous plants as they feed on insects. As
   most of these plants are green, they can prepare their food by photosynthesis. Poor
   environmental soil supplements their diet by carnivorous habits. These plants are
   adapted to trap, capture and digest insects. These traps are mostly the modification
   of leaves.
4. Pitcher plant – The leaf is modified in pitcher shape to trap and capture insects.
   The front part of petiole is coiled like a tendril that holds the pitcher in erect
   position. The leaf tip forms the lid. Its leaf is filled with a liquid to collect and
   digest insects.
5. Bladderwort – In this plant, the leaves are highly segmented and modified into
   sacs called bladders. The bladder has a trap door in which the minute organisms
   can only go but cannot come out. It can be observed in aquatic plants.
6. Venus flytrap – In this plant, the edge of leaf has long pointed stiff hair. The leaf
   blade is divided into two parts and the midrib acts as hinge of the door. When
   any insects touch the leaf, the edge of leaf interlocks and prevents the escape of
   insect.
   Vegetative Propagation –
   It is an asexual method of reproduction in plants. In this method, new plants are
   produced from the parts of a plant like roots, stems, and leaves. This process is
   known as vegetative propagation. It usually involves the growth and development of
   one or more buds on the vegetative parts of an old plant. After providing suitable
   conditions to the bud, it grows to form a new plant. Example – rose and champa.
   Vegetative propagation in leaves –
   In this method, plant grows from leaves. Leaves of some plants develop buds on
   them. Such leaves having buds are used for vegetative reproduction. Example –
   Bryophyllum.
   

Artificial Vegetative Propagation –
The methods of vegetative propagation which are developed by man are called
artificial vegetative propagation. Some of the methods are –

1. Cutting – In this method, the stems of the plants are cut into small pieces. Each
   stem is kept in moist soil. After some time, roots develop at the base and new
   plant develops. Example – rose and sugarcane.
2. Grafting – This method is used to obtain a plant by combining two different
   plants. Thus, it produces a variety with the features of two different plants. In
   this method, a stem cutting called scion (without roots) from one plant is
   attached to the other stem cutting part of stock (with roots). After few days,
   both fuses and new cells develop having characteristics of both plants. Example –
   mango and lemon.
3. Layering – In this method, a branch of a plant is pulled and its part is covered
   with moist soil leaving the top part outside in the air. After some time, new roots
   develop from buried part and it grows to become a new plant. Example –
   layering is done in jasmine.
4. Tissue culture – It involves growing of plants in test tubes. A small piece of plant
   is grown in suitable conditions in the test tube. An organized mass of cell is called
   callus develops from it. It is put in hormone containing medium which include
   cell differentiation and formation of plantlets. These plantlets grow into an
   independent plant when transferred to the soil. Example – orchid.
   Advantages of Vegetative propagation –
5. It is faster method to grow new plants.
6. There is no difference between produced plant and parent plant.
7. It is very useful for production of seedless plants.
8. The plants produced by this method bear flowers and fruits earlier than the
   plants produced by seeds.
   Disadvantages of Vegetative propagation –
9. All the plants produced by this method have same features. Thus, they are likely
   to be infected by the same infections.
10. It can results in destruction of entire crop. As there is no dispersal of plants,
    there are chances of overcrowding

Health-
Physical and mental fitness is must for healthy mind of an individual. WHO has defined
health as state of complete physical, mental social well being and not merely the absence of
disease or infirmity.
A disease may occur due to following reasons: viruses, bacteria, fungi.

TYPES OF DISEASES:

▪ CONGENITAL DISEASES:
Diseases which are already present in the body since birth are called congenital
diseases.
Causes- genetic abnormality or when organ in the body is not fully developed.
Eg- colour blindness, haemophilia , thalassaemia.
Colour blindnessColour blindness is due to vision problem. This is because person lacks certain
pigments in eyes therefore it is called colour vision deficiency.
Most common colour blindness is red green colour deficiency.

Haemophilia: In this disease blood loses its ability to clot.

Thalassaemia: In this disease body makes haemoglobin and red blood cells lesser than normal
value.
It ultimately causes amaemia.

Acquired diseases:
Two categories- 1- communicable
2-Non communicable
1- Communicable or infectious diseasesDirectly or indirectly infection is paased from infected person to healty person.
Eg. Viruses ,bacteria.
2- Non communicable or non infectious diseasesDirectly or indirectly the diseases is spread from person to person or by
microorganisms.

COMMUNICABLE DISEASES :This diseases are classified on the basis of oraganisms that cause diseases.
Mode of spread- air, water, food from infectef persons
Diseases caused by bacteria

1- Tuberculosis-
• Causative organism- mycobacterium tuberculosis
• Incubation period: 2-10 weeks It is period between exposure to the
infection and appearance of first symptom
• Symptoms- Cough, sputum with blood, pain in chest, loss of
weight,etc
2- Cholera-
• Causative organism- vibrio cholera
• Incubation period- few hours to 5 days
• Symtoms- acute diaarhoea, vomiting dehydration, extreme thirst and
muscle cramp.
3- Typhoid-
• Causative organism- Salmonella thyphi
• Incubation period- 7-12 days
• Symptoms- high fever in afternoon, acute headache, reddish eruptin
on chest.
4- Leprosy-
• Causative organism- mycobacterium leprae
• Incubation period- several years
• Symptoms- loss of sensation, skin eruptions and deformation of skin
and toes.
5- Tetanus-
• Causative organism- clostridium tetani
• Incubation period- 4-20 days
• Symptoms- painful contraction of muscles, neck amd jaw followed by
paralysis.

Diseases caused by virusesCommon colddroplet infection spreads through moisture.
Incubation period- 1-3 days
Symptoms- running nose, headache , fatigue
InfluenzaDroplet infection
Upper respiratory tract infection
symptoms- fever, cold , chill, body ache
.
Measles Mode of transmission– direct contact through infected saliva and mucous
Symptoms- nasal discharge, redness of eyes and coughing.
ChickenpoxTransmission– contact with skin sores and clothes of patient
Incubation time- 14-16 days.
Symptoms– fever, head ache, small watery sores on skin
PolioAffects liver
Types- Hepatitis A,B,C,D,E,G,H

Causative organism- Human deficiency virus
Spread- sexual contact
Incubation period- 15 months- 5 years
Transmission- can transmit virus from mother to child
Precaution- Avoid sexual contact with infected person

DISEASE CAUSED BY PROTOZOA-
• AMOEBIASIS-
✓ caused by entamoeba histolytica
✓ Transmission- contaminated food and water
✓ Symptoms- diarrhoea, gripping pain, discharge of mucous
✓ Incubation period- one week
• Malaria-
✓ Caused by- Plasmodium
✓ Transmission- bite of female anopheles mosquit0
✓ Symptom- chillness, sever head ache, rising temperature
Diseases caused by worms

AIDS

1. Elephantiasis {Filaria}
   ▪ Causative organism- Wucheria bancrofti
   ▪ Spread-female culex mosquito
   ▪ Symptom- lympnodes in limbs, scotrum in males and breast in females.
2. Ascariasis-
   ▪ Occurs in small intestine
   ▪ Causation- Ascaris lumbricoides Spread- unsafe food and water
3. Taeniasis-
   ▪ Caused by tapeworm
   ▪ Symptom- pain, weight loss, digestive problems.
   TRANSMISSION OF COMMUNICABLE DISEASES
   Airborne diseases or droplet infectionBacteria, spores of fungi and viruses enter our body through inspiration and attack our
   throat, wind pipe and lungs.
   Microbes are present in saliva and blood
   When person sneezes in public places droplets are spread in air and transmitted to healthy
   person
   
   WATER BORNE AND FOOD BORNE DISEASES
   • Water is polluted in so many ways.
   • Dumping of sewage water in water bodies is cause of disease.
   • Uncleansed food contains bacteria and eggs of parasite; if not washed properly than
   diseases like diarrhoea and vomiting occur.
   • Botulism is serious food poisoning due to special bacterium.
   INSECT BORNE OR VECTOR BORNE
   o Organisms which carry disease containing pathogens to a healthy person without
   getting affected.
   o Contact diseases: spreads from one person to anothe directly or indirectly.
   o Unsanitary toilet habits should be avoided.
   Eg; conjunctivitis, chicken pox, common cold, etc.
   WAYS TO PREVENT COMMUNICABLE DISEASES
   o We should be very much careful regarding our personal cleanliness by taking a
   regular bath with good soap and shampoo.
   o Cove your nose and mouth with a tissue or handkerchief while coughing or sneezing.
   Do not forget to throw the tissue.
   o We should avoid using bathrooms and lavatories of railway station and cinema hall.
   o We should dustbins.
   o Food items exposed to flies should not be used.
   NON COMMUNICABLE DISEASES
   Nutritional deficiency diseases
   When all nutrients are done in right amount and ratio according to need its called balanced
   diet.
   A.PROTEIN ENERGY MALNUTRITION
   Deficiency of protein, fats and carbohydrates is called protein energy malnutrition.
   Eg- Kwashiorkor and marasmus
   Kwashiorkor- results due to diet poor in protein.
   Symptoms- protruding belly, mental retardation, bulging eyes, etc.
   
   Marasmus- Deficiency of proteins and carbohydrates.
   Child may suffer mental retardation.
   No change in skin colour and ribs look prominent and becomes thin.
   B. VITAMIN DEFICIENCY DISEASES
   Vitamins are vital though they are required in small quantities.
   1- Night blindness is caused by vitamin A
   2- Rickets are caused by vitamin D
   3- Haemolysis and sterility are caused by vitamin E.
   C. MINERAL DEFICIENCY DISEASES
   Metals and non-metals and their salts are called minerals.
   They do not supply energy to body.
   1- Muscle cramps is caused by deficiency of sodium
   2- Weakness of muscles or paralysis is caused by potassium
   3- Rickets is caused by deficiency of calcium
   DISEASES DUE TO MALFUNCTIONING OF ORGANISMS:
   • Diabetes mellitusIt is a hereditary disease
   When insulin secreted by pancreas is not in enough amounts than it can neither use the
   sugar nor store in liver in form of glycogen.
   Than sugar level becomes high. This is called diabetes mellitus.
   • Heart diseasesCoronary artery diseases and atherosclerosis are common.
   The blood vessels that supply blood to heart muscles are called coronary arteries. And
   arteries become hard its called atherosclerosis.
   The blood supply is reduced due to which heart muscles don’t get proper supply its called
   coronary artery disease.
   • Arthritis :It is joint disease.
   Found as two types – rheumatoid arthritis and osteoarthritis.
   
   • CANCER :It is characteristic by uncontrolled cell division.
   Malignancy refers to growing mass of cancerous cells. Renal disease or malfunctioning of
   kidney Due to some reason if kidney is malfunctioning and waste material accumulating in
   body is called uraemia. Due to head ache and extreme fatigue patient may go into coma.
   • ALLERGY :Unusual hypersensitivity of body tissues.
   Substances causing it are called allergens.
   • Asthma: Respiratory passage become swollen and constricted.
   Symptoms include coughing at night and shortness of breath, etc.
   BITES AND STINGS
   It needs immediate medical attention and is dangerous.
   Bite of snake may be dangerous and that of mosquito may be serious sometimes in case of
   carrier.
   BURNS AND FIRST AID
   First degree of burns is superficial burned
   Second degree of burns is called serious burns.
   Third degree of burn is called severe burns.
   CUTS AND THEIR FIRST AID
   If the cut is not deep is called superficial cut.
   If the cut is deep a cloth or pad should be kept on cut
   Bruises are injuries under the skin.
   Ways to prevent communicable diseases
   ❖ Diet and exercise play an important role
   ❖ Regular health screening and doctor check-up
   ❖ One should avoid fast food
   
   CLEANLINESS, HYGIENE, EXERCISE
   • Always eat clean and healthy food.
   • Always wash hands after and before meal
   • Never split in public places
   • Always cover your mouth and nose while sneezing.
   • Always take a balanced and healthy diet.
   BAD HABITS LEAD TO ILL HEALTH
   • Tobacco addiction- chewing of tobacco may lead to cancer of mouth
   • Drug addiction- symptoms like nausea, vomiting and pain in stomach may occur’
   • Addiction of fast food- they have dangerous effect on health
   • Alcohol consumption- it retards mental health and driving under influence of alcohol
   may cause accident
   • Unhealthy lifestyle- absence of physical activity and workout than unhealthy lifestyle
   increase the risk of heart ailments, blood pressure, and obesity and also makes us
   feel stressed

Map – A map is a representation or a drawing of the earth’s surface or a part of it drawn on a flat surface according to a scale.

Atlas – When many maps are put together we get an Atlas. Atlases are of various sizes, measurements drawn on different scales.

They are of different types of maps. Some of them are described below.

Physical Maps

Maps showing natural features of the earth such as mountains, plateaus, plains, rivers, oceans etc., are called physical or relief maps.

Political Maps

Maps showing cities, towns and villages, and different countries and states of the world with their boundaries are called political maps.

Thematic Maps

Some maps that focus on specific information; such as road maps, rainfall maps, maps showing distribution of forests, industries etc., are known as thematic maps.

There are three Components of Maps – distance, direction and symbol

Distance

Scale is the ratio between the actual distance on the ground and the distance shown on the map. Scale is very important on any map. If you know the scale, you will be able to calculate the distance between any two places on a map. When large areas like continents or countries are to be shown on paper, then we use a small scale. It is called a small scale map. When a small area like your village or town is to be shown on paper, then we use a large scale that is 5 cm. It is called a large scale map.

Direction

There are four major directions, North, South, East and West. They are called cardinal points. Other four intermediate directions are north-east (NE), southeast (SE), south-west (SW) and north-west (NW). We can find out the direction of a place with the help of a compass. It is an instrument used to find out main directions. Its magnetic needle always points towards north-south direction.

Symbols

It is the third important component of a map. It is not possible to draw on a map the actual shape and size of different features such as buildings, roads, etc. So, they are shown by using certain letters, shades, colours, pictures and lines. These symbols give a lot of information in a limited space. Maps have a universal language that can be understood by all. There is an international agreement regarding the use of these symbols. These are called conventional symbols.

Various colours are used for the same purpose. For example, generally blue is used for showing water bodies, brown for mountain, yellow for plateau and green is used for plains.

Sketch

A sketch is a drawing mainly based on memory and spot observation and not to scale. Sometimes a rough drawing is required of an area to tell where a particular place is located with respect to other places. Such a rough drawing is drawn without scale and is called a sketch map.

Plan

A plan is a drawing of a small area on a large scale. A large-scale map gives a lot of information, but there are certain things, which we may sometimes want to know, for example the length and breadth of a room, which can’t be shown in a map. At that time, we can refer drawings drawn to scale called a plan

Mountains

• A mountain is any natural elevation of the earth surface.
• There are permanently frozen rivers of ice. They are called glaciers.
• Mountains may be arranged in a line known as the range.
• The Himalaya, the Alps and the Andes are mountain ranges.
• There are three types of mountains—Fold Mountains, Block Mountains and Volcanic Mountains.
• The Himalayan Mountains and the Alps are young fold mountains.
• The Aravalli range in India is one of the oldest fold mountain systems.
• Block Mountains are created when large areas are broken and displaced vertically.
• Volcanic mountains are formed due to volcanic activity, e.g. Mt. Kilimanjaro in Africa

Plateaus

• A plateau is an elevated flat land.
• The Deccan plateau in India is one of the oldest plateaus.
• The Tibet plateau is the highest plateau in the world.
• The African plateau is famous for gold and diamond mining.
• The lava plateaus are rich in black soil that are fertile and good for cultivation.

Plains

• Plains are large stretches of flat land.
• Most of the plains are formed by rivers and their tributaries.
• In India, the Indo-Gangetic plains are the most densely populated region of the country

Landforms and the People

• Humans have been living in different kinds of landforms in different ways.
• Sometimes, natural calamities such as earthquakes, volcanic eruptions, storms and floods cause widespread destruction.

The surface of the earth is not the same everywhere.

Mountains, plateaus and plains are different landforms of the earth.

A mountain is a natural elevation of the earth surface. There are three types of mountains—Fold mountains, Block mountains and Volcanic mountains.

A plateau is an elevated flat land. It is a flat-topped table land standing above the surrounding area. A plateau may have one or more sides with steep slopes.

The Deccan plateau is one of the oldest plateaus.

The Tibet plateau is the highest plateau in the world.

Plains are large stretches of flat land. Some plains are extremely level while others may be slightly rolling and undulating

Plains are generally thickly populated regions of the world

Human habitation is found on different kinds of landforms. But population varies on these landforms. Mountains are generally not thickly populated. But plains are the regions where the thick population is found.

The land is precious. We must not use it in a wasteful manner. Construction work of any type should not be carried on fertile land. Also, we should not throw garbage on land. It is our duty to take care of the land or any other natural gift. If we do this we will be conscious citizens.

Erosion: The wearing away of the earth’s surface is known as erosion.

Mountain: A mountain is a natural elevation of the earth surface.

Glacier: Some mountains have permanently frozen river of ice. They are called glaciers.

Range: When mountains are in an arranged line, it is called a range.

Horsts and graben: The uplifted blocks are known as horsts and the lowered blocks are known as graben.

Storehouse: A building where things are stored or kept.

Terraces: One of the series of flat areas of ground which are cut into the side of a hill like steps in order to grow crops there.

Flora: The plants of a particular area.

Fauna: The animals living in an area.

Plateau: A plateau is an elevated flat land. It is a flat-topped table land standing above the surrounding area.

Plain: A plain is a vast stretch of flat land where the thick population is found.