NCERT Class 6 Science Chapter 7: Getting to Know the Plants YouTube Lecture Handouts

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NCERT Class 6 Science Chapter 7: Getting to Know About Plants

Living (Biotic) and Non-Living (Abiotic) Things

Illustration: Living (Biotic) and Non-Living (Abiotic) Things

Variety in plants & animals, their dwelling and adaptation and modification

Illustration: Living (Biotic) and Non-Living (Abiotic) Things

Variety within Variety

Federation Cynologique Internationale, an organisation with 65 member countries, lists 335 different breeds of dogs. Usually Kennel clubs group them as sporting dogs, working dogs, terriers, sheep dogs and so on. This is a variety within the variety.

Panda is a rare and beautiful animal found in between the elevations of 1,800 to 4,000 metres. It is found in great Himalayans heights and Central China only. Lush green, young leaves and pencil thin stains of bamboo are panda՚s main diet

Morphology

  • Morphology implies study of external features. It is the description of the body of organism & means the description of body parts – shape, texture and arrangements
Illustration: Morphology

Classification of Plants

Herbs – green, tender stems, short with no branches

Shrubs – hard but not thick stem

Trees – hard and thick stem

Creepers – Spread on ground

Climbers – climb up with support have tendrils or hooks to help in holding a support

Weeds – unwanted plants

Stem

  • Conducts water – like ink, mineral dissolved in water moves up the stem along with water
  • Stem is cut half into and put in two separate containers
Illustration: Stem
  • Stem we eat – sugarcane, celery
  • The stem of the twig contains narrow tubes (special cells) for transportation of water and minerals to other parts of the plant

Leaf

  • Petiole – attached to stem
  • Lamina – broad green part of leaf
  • Veins – lines all over lamina
  • Leaf Venation – design made by the leaf
  • Center leaf – midrib
Illustration: Leaf
  • Venation can be
  • Reticulate – peepal, rose
  • Parallel – wheat, grass, banana, coconut (mainly monocots)
  • Tie a bag on tree – water droplets
  • Water comes out of leaf as transpiration into the air (water is released in atmosphere in form of water vapors by leaves)
Illustration: Leaf
  • Leaves prepare the food in presence of sunlight & green colored substance – chlorophyll; it uses water and carbon dioxide from air in process called photosynthesis – oxygen is released and food is prepared which is stored as starch
  • Leaf in spirit and boil – green colored spirit and reacts with iodine (color turns blue black) to show starch (but won՚t happen in dark)
  • Only those parts of the leaf which were not covered by the paper, show the presence of starch. It is because only the cut out design could get the sunlight and prepared the starch in the presence of light.
  • Stem supplies leaf with water. The leaf uses the water to make food. The leaves also lose water through transpiration
  • Leaves we eat – lettuce, spinach

Root

Water that comes in from roots – with roots plant will have normal growth and development as roots also help in the absorption of water and minerals

If we cut the roots – plant will not be healthy & die

Roots help to hold the plant firmly in the soil – anchor the plant to soil

Taproot – main root with smaller roots called as lateral roots - Amaranths

Fibrous Roots – all roots are similar (mainly monocots) – grass

Illustration: Root

Roots we eat - carrot, radish, potato, sweet potato, turnip and tapioca.

Flower

Petals (Corolla) – joint or separate

Sepals (Calyx)

Stamens (includes anther and filament)

Pistils (Ovary, Stigma and Style)

Pistil – Innermost part of flower (one or more carpels form pistils)

Illustration: Flower

Longitudinal Section & Transverse Section of Ovary

Ovary will have ovules

Forms fruits. Fruits has seeds

Seeds we eat - corn

Stamens and ovary can be in the same flower, for example, hibiscus, okra, cotton, pimento, tomato, tobacco.

Stamens and ovary can be in different flowers. Then there are male flowers and female flowers, for example, in maize and oil palm.

Stamens and ovary can be in different flowers and on different plants.

In the papaya tree, the male flowers and the female flowers are not on the same tree. There are male papaya trees and female papaya trees. Only the female papaya trees bear fruit.

✍ Mayank