The Living Organisms And Their Surroundings

A cultivated land is used for planting crops and grazing cattle. It cannot be called a habitat because the animals do not live there. A habitat refers to the natural environment or surroundings where a particular organism lives. It is characterized by both physical and biological features.

Desert is a place which receives very little rainfall (less than 25 cm per year). The plants growing in a desert are well adapted for storing water to overcome the harsh environmental conditions. They lose very little water through transpiration to conserve water and their roots grow deep into the soil to absorb water.

A stream-lined and slippery body is the characteristic feature of aquatic organisms. The stream-lined body of aquatic animals helps them move easily in water. Possessing a streamlined body reduces resistance when moving whereas a slippery body provide resistance to parasites and also help some animals to breathe through their skin.

Some of the characteristics are common to all living beings, such as, growth and reproduction, excretion, adaptation, respiration, response to stimuli, etc. Organisms have different mechanisms for these life processes according to their habitat. Some organisms respire through lungs, gills and also through skin. Similarly, the excretory product is not the same for all living beings.

Earthworms do not have lungs or gills, rather they breathe through their moist skin. Their body is covered by a mucus layer. Air dissolves on the mucus of their skin, so they must stay moist to survive.

Stimulus is a change in our surroundings that make us respond to it. A chick hatching out of an egg is an example of growth. It is not initiated by the change in surroundings. On the other hand, mouthwatering, closing of leaves and shutting of eyes are all examples of response to stimuli.

Exchange of gases in plants takes place through their leaves. They take in oxygen through their tiny pores in leaves and give out carbon dioxide to air. Respiration in plants occurs both during day and night, but they produce their food through photosynthesis only during daytime.

Excretion refers to the process of getting rid of waste materials produced by the body, and not only excess water. Waste products consist of undigested food, some poisonous materials, excess water, etc.

The living things, such as plants, animals, and insects constitute the biotic components of a habitat, whereas the non-living things such as rocks, soil, sunlight, etc constitute the abiotic components.

Reproduction refers to the process by which living organisms produce offspring of their own kind. A new leaf coming out of a tree branch is an example of growth and not reproduction.

Different organisms have different mode of reproduction. The seeds, buds and eggs are a means of reproduction. These parts help the organism to produce more of their own kind. But, a mango tree does not reproduce through roots, rather it reproduces by seeds.

Reproduction refers to the process by which living organisms produce offspring of their own kind. It takes place in many different ways, for different organisms. It helps to increase the population of a particular species.

In a desert, there is scarcity of water. So the organisms tend to conserve water by different adaptations. Similarly, we will excrete concentrated and less amount of urine to prevent loss of water from the body.

(a) Adaptations

Adaptation is the process of change by which an organism becomes better suited to its environment.

(b) Excretion

Excretion refers to the process of getting rid of waste products.

(c) Stimuli

Stimulus is a change in our surroundings that make us respond to it.

(d) Reproduction

Reproduction refers to the process by which living organisms produce offspring of their own kind.

(a) Deer lives in grasslands and forests.

(b) Frog lives in ponds and is adapted to aquatic habitat.

(c) Mountain goats are adapted to mountain habitats.

(d) Camel lives in desert and is adapted to dry weather conditions.

Grassland – Terrestrial habitat

Pond, ocean, Rice field – Aquatic habitats

Terrestrial habitats are ones that are found on land, like forests, grasslands, deserts, shorelines, and wetlands. An aquatic habitat is a habitat with water. It includes areas that are permanently covered by water and surrounding areas that are occasionally covered by water.

Reproduction refers to the process by which living organisms produce offspring of their own kind. It is important for the survival of all living beings. Without reproduction, life would come to an end. It is an essential process that ensures continuity of a particular species on Earth. Different organisms have different mode of reproduction, but the same purpose is served, i.e. increase in the number of individuals of a species.

(a) Abiotic

The non-living things such as rocks, soil, air, water, and sunlight constitute the abiotic components of a habitat.

(b) Water

An aquatic habitat is a habitat with water. It includes areas that are permanently covered by water and surrounding areas that are occasionally covered by water.

(c) Adaptations

Adaptation is the process of change by which an organism becomes better suited to its environment.

(d) Terrestrial

Terrestrial habitats are ones that are found on land, like forests, grasslands, deserts, shorelines, and wetlands.

She needs to cut a piece of strong and healthy rose stem about 6 inches long and remove the bottom set of leaves. Next, she needs to stick the stem into a pot of garden soil, a couple inches deep. She must periodically water the soil, otherwise the rose stem will dry out. She will observe new shoots sprouting form the buds. Repeated this procedure with a number of stems cuttings and she will have many rose plants in her garden.

Deserts are usually very dry. During the daytime, the sun shines brightly and heats up the desert sand, raising the temperature extremely high. Because of the lack of water, deserts cannot support much vegetation. Due to this, there is fluctuation in temperate. During the night the sand loses all its heat and becomes cool. To stay away from the intense heat, desert snakes burrow deep into the sand during the day and come out only during the night, when it is cooler.

(a) Some aquatic plants are totally submerged in water. All parts of these plants grow under water. These submerged plants have narrow and very thin ribbon-like leaves, that enable them to bend in flowing water.

(b) The stems of some aquatic plants are long, hollow and light. These stems grow and reach up to the surface of water and the leaves can float on the surface of water.

(a) The body structures of camels help them to survive in deserts. They have long legs that keep their body away from the hot sand. Due to their long legs, their body remains at a fair distance from the sand. Also, the camels do not sweat.

(b) Frogs can live both on land and in water. They have certain adaptations for aquatic habitat. They have webbed feet that help them to swim in water. Webbed feet reduce resistance while movement.

(c) Since dolphins and whales do not possess lungs for breathing, they breathe through their nostrils or blowholes that are present on the upper part of their head. They swim near the surface of water and breathe in air. This enables them to stay inside water for a long time without breathing.

Desert plants are well adapted to the harsh conditions. Due to water scarcity, they need to conserve water. Some of the desert plants have very small leaves whereas some have only spines to reduce water loss through the process of transpiration. This adaptation helps the plants to conserve water.

A deer needs to have certain features for its survival and to protect itself from predators such as a lion. A deer has long ears to hear movements of predators. The eyes present on the sides of the head enable it to look in all directions. The deer runs at a high speed that helps it to escape predators. All these features helps the deer to detect the presence of predators.

(a) Thick waxy stem – Desert plant

The thick waxy coating on the stem of desert plants helps to retain water.

(b) Short roots – aquatic plant

In aquatic plants, roots are much reduced and do not play a role in water absorption. Their main role is to hold the plant in place.

(c) Cone shaped plants – Mountainous plant

The cone shape of plants helps the rainwater and snow to slide off easily from the plant.

(d) Sloping branches – Mountainous plant

The sloping branches help the rainwater and snow to slide off easily from the trees.

(e) Small or spine-like leaves – Desert plant

The reduced leaves of desert plants help to reduce loss of water through transpiration and thereby conserve water.

(f) Hollow stem – Aquatic plant

The stems of some aquatic plants are hollow and light so that they grow and reach up to the surface of water.

● Although a car also moves it is not considered as a living organism.

● All living organisms have certain common characteristics, such as respiration, growth and reproduction, movement, excretion, response to stimuli, etc.

● A car does not show respiration, which is an essential process for living organisms.

● It does not exhibit reproduction, a process that ensures continuity of species. It does not produce more its own kind.

● Although it shows movement, but it does respond to any stimulus.

● Due to the absence of common life processes, a car is considered as a non-living organism.

A lion is a strong and fierce animal that hunts and kills other animals. It has specific adaptive features that help it in hunting:

● Lions are nocturnal, i.e. they hunt at night that enables them to sneak up on their prey.

● Its light brown colored body helps it to hide in dry grasslands and easily hunt for a prey – camouflage

● The eyes situated in front of the face enables it locate its prey easily.

● It has long and sharp claws in its front legs that can be withdrawn inside the toes. The claws help the lion to attack its prey.

● A lion’s tongue is rough enough to peel off the skin of its prey.