Kami Export - Ch 2_ Diversity in the Living World PPT (1).pdf

Ch 2 : diversity in the living world  On the basis of their size and nature of Stem, plants can be classified as: NOTE: This topic is already covered as Topic I- Types of Plant from Bridge Course  LEAF VENATION The pattern of veins on a leaf is called venation...

Ch 2 : diversity in the living world  On the basis of their size and nature of Stem, plants can be classified as: NOTE: This topic is already covered as Topic I- Types of Plant from Bridge Course  LEAF VENATION The pattern of veins on a leaf is called venation. It is of two types: RETICULATE VENATION PARALLEL VENATION ❏ If the pattern of veins is ❏ If the pattern of veins is net-like on both sides of the parallel to each other or to the thick middle vein (midrib), it midrib, then it is called is called reticulate venation. parallel venation. ❏ Eg. hibiscus, rose, peepal ❏ Eg. grass, banana, maize  TYPES OF ROOTS THERE ARE TWO TYPES OF ROOT SYSTEMS: TAP ROOTS FIBROUS ROOTS Eg.:Carrot, Radish, Beetroot, Eg.:Grass,Banana,Wheat, Turnip, Peas, Mango,Neem Rice  TAP ROOTS FIBROUS ROOTS 1. TAP ROOT HAS ONE LONG AND MAIN ROOT (CALLED TAPROOT). SMALLER 1. FIBROUS ROOTS DO NOT HAVE ONE VEINS ARISE FROM BOTH SIDES OF MAIN ROOT. ALL ROOTS SEEM THE TAPROOT, CALLED LATERAL SIMILAR. ROOTS. 2. THEIR ROOTS DO NOT GO DEEP INTO 2. THEIR ROOTS GO DEEP INTO THE THE SOIL. SOIL. 3. EG. CARROT, RADISH, BEETROOT, 3. EG. GRASS, MAIZE, RICE, BANANA TURNIP, MANGO CORIANDER FIBROUS ROOT IN GRASS CARROT  DICOTS & MONOCOTS DICOTS: Plants that have seeds with two cotyledons are called dicotyledons (dicots). MONOCOTS: Plants that have seeds with one single cotyledon are called monocotyledons (monocots). RELATION BETWEEN Type of Type of Root Dicots/ Examples LEAF VENATION, Venation Monocots TYPES OF ROOTS and Reticulate Taproot Dicots Chickpea, peas NO. OF COTYLEDONS IN A SEED OF A PLANT Parallel Fibrous root Monocots Maize, wheat  Dicot plants have reticulate venation and a taproot system while monocot plants have parallel venation and a fibrous root system. Eg., Chickpea is a dicot and maize is a monocot. Ques 1. If a plant has taproot system, then what is its leaf venation likely to be? Ans. Reticulate Venation Ques 2. What is the type of venation and roots in grass? Ans. Parallel venation and Fibrous roots  HABITAT The place where organisms live is called habitat. Habitat means a dwelling place (a home). The habitat provides food, water, air, shelter and other needs to organisms. Several kinds of plants and animals live in the same habitat Ques. Differentiate between terrestrial and aquatic habitat Terrestrial habitats Aquatic Habitat The place where plants and The habitat of plants and animals that live on land are animals that live in water is called terrestrial habitats. Some examples of terrestrial called as aquatic habitat. habitats are forests, grasslands, Lakes, rivers and oceans are deserts, coastal and mountain some examples of aquatic regions. habitat. Ques. What is Adaptation? Ans. The special features which enable a plant or an animal to live in its surroundings is called adaptation. These changes take place over thousands of years. Example- gills in fish and hump in camels. Biodiversity of different regions varies because of distinct environmental conditions. Ques. How does fish survive in water? Streamlined body Gills Streamlined body- helps water to easily flow around it. They have fins and a tailfin to maintain balance while swimming. Gills present in the fish help them to use oxygen dissolved in water for respiration. Slippery scales-protect the body. Ques. What is the habitat of a frog? Frogs can live in water as well as on land. Such animals are called amphibians. Frogs breathe in water with the help of their moist skin, whereas they breathe on land with the help of lungs.  Ques. Differentiate between camels in a hot desert and camels in a cold desert. Camel in hot desert Camel in cold desert 1. These camels have long legs with 1. Camels in cold deserts, such as those wide hooves. The long legs and wide in Ladakh, have shorter legs. This hooves help them walk on sandy adaptation allows them to navigate the deserts without sinking into the sand. mountainous regions more easily  Camel in hot desert Camel in cold desert 2. They have one hump that stores food, 2. These camels have two humps that helping them survive during food scarcity shrink in late winters because there is not much food available in the cold desert and they have to use food stored in their humps during that time. 3. They do not have long hair since 3. They grow long hair from head to they live in an environment with extreme neck to survive the cold winters of heat during the day and cold at night, Ladakh (cold desert). but not as cold as in the cold deserts NOTE: Camels in hot desert regions excrete small amounts of urine, have dry dung, and do not sweat. These adaptations help them conserve water, allowing them to survive for many days without drinking water.  Ques. How is cactus adapted to survive in a hot desert? Cactus have thick, fleshy stem to store water. Their green stem also prepares food by photosynthesis. Leaves in a cactus are modified to spines, which helps in reducing loss of water from the leaves. Most desert plants have roots that go very deep into the soil to absorb water. The stem is also covered with a thick waxy layer, which helps to retain water. Ques. What are the adaptations of rhododendrons? Habitat: Mountainous regions Rhododendrons in the Shola forests of Nilgiris are shorter in height and have smaller leaves. This adaptation helps them survive the heavy winds on mountain tops. In contrast, rhododendrons in Sikkim are observed to be taller. This shows how rhododendrons can exhibit different features depending on the region they grow in to adapt to the specific environmental conditions Ques. What are the adaptations of deodar trees? Habitat: Mountainous regions The trees growing on mountains are normally cone- shaped and have sloping branches. The leaves of some of these trees are needle-like as in deodar and pine trees. This helps the rainwater and snow to slide off easily, so as to protect them from the weight of accumulated snow. Cone-shaped trees  Janaki Ammal (1897–1984) was an Indian botanist dedicated to environmental work and helped to document and preserve India’s rich plant biodiversity. She played a key role in the ‘Save Silent Valley’ movement. Salim Ali (1896–1987) travelled across India to observe diversity in birds. He is referred to as the ‘Birdman of India’.