PLANT LIFE ICSE CLASS VI
- VERY SHORT TYPE QUESTION
1) Name two plants which grow new plants from leaf.
Ans. Bryophyllum and Begonia.
2) What is complete flower?
Ans. A flower having all four whorls is called complete flower.
3) What is thalamus?
Ans. Swollen base of flower is called thalamus.
4) What is unisexual flower?
Ans. Flower with either the androecium or the gynoecium is called unisexual flower. e.g. Pumpkin.
5) Which part of flower develops into seed?
Ans. Ovule develops into seed.
6) Which part of flower develops into fruit?
Ans. Ovary develops into fruit.
7) Which parts are present in bisexual flower?
Ans. All four parts – Calyx, Corolla, Stamen and Carpel, are present in bisexual flower.
8) What is floret?
Ans. Each flower in an inflorescence is called a floret.
9)Give some examples of wind pollinated flower.
Ans. Wind pollinated flowers are Maize, Rice, Wheat.
10)Give some examples of water pollinated flower.
Ans. Water pollinated flowers are Vallisneria and Hydrilla.
11)Give some examples of Insect pollinated flower.
Ans. Insect pollinated flowers are Sunflower, Marigold, Banyan.
12)Name some other agents other than wind, water and insect.
Ans. Humming bird, Snail and Bats.
- FILL IN THE BLANKS:
1) Male cells are present in _______
2) In vegetative propagation, plants develop from parts other than the __________
3) Each part of ______ is known as sepals.
4) Pollination is the transfer of pollen from _____ to stigma.
5) _________ covering of seed is called Testa.
6) The place where seed is attached to the fruit is known as ______.
7) Right below the hilum is a small _____ called micropyle.
8) In ______ the pericarp and seed coat are fused.
9) During germination water softens the seed coat to activate _______ of seed cell so that stored food is available to the growing embryo.
10)The root of embryo is called _______ and shoot of embryo is called ______.
Ans. Radicle ; Plumule.
- SHORT TYPE QUESTION
1) What self-pollination?
Ans. Transfer of pollen grain from another to the stigma of the same flower or another flower of the same plant, is called self-pollination. e.g. Apricot, Fig, Plum, Rose, Tomato, Sweet Pea.
2) What is cross pollination?
Ans. Transfer of pollen grain from the another of one flower of one plant to the stigma of a flower of another plant is called cross pollination. It is found in most of the flowers.
3) What are the agents of Pollination?
Ans. Pollen is transferred by various agents like wind, water and insects.
4) Write down the characteristics of wind pollinated flower.
Ans. Characteristics of water pollinated flower
- i) Female flowers bloom at the surface of flower.
- ii) Light weight pollen grain to be carried by wind
iii) Anthers should have long filament.
5) Write down the characteristics of water pollinated flower.
Ans. Characteristics of water pollinated flower
- i) Female flowers bloom at the surface of flower.
- ii) Pollen grains have spongy layer to prevent soaking.
iii) Male flower may float to reach female flower.
6) State the characteristics of Insect pollinated flower
Ans. Characteristics of Insect pollinated flower are:
- a) Attractive flower with colourful petals
- b) It produces nectar
- c) It has sweet scent
- d) Night flowers are white in colour but having good smell.
7) What is fertilization?
Ans. Fertilization is the process by which a male cell unites with a female cell to produce a single cell from which a new individual grows. In plant, fertilization take place after pollination.
8) Why is dispersal of fruit necessary?
Ans. Fruit dispersal is necessary for scattering of seeds. If seeds did not get scattered, they would fall right under the parent tree. The new young plant would then complete with the parent and with each other for space, water, air, light etc.
9) Mention the parts of fruit.
Ans. A fruit has two parts pericarp and seed. Pericarp is divided into epicarp (fruit coat) mesocarp (fleshly part) and endocarp (Protection covering of seed).
10) What is fleshly fruit?
Ans. Fruit which is having fleshy mesocarp or fleshy mesocarp and endocarp is called fleshly fruit. e.g. Mango, Tomato, Grape.
11) What is dry fruit?
Ans. Fruit where three layers of pericarp are not distinguished is called dry fruit. e.g. Rice, Maize, Pea.
12) Why some fruits are called false fruit?
Ans. Some fruits are developed from another part of flower other than ovary is called false fruit. e.g. Apple which is developed from Thalamus.
13) Why true fruits are named so?
Ans. Some fruits which are developed only from the ovary are called true fruit. e.g. Mango, Cherry etc.
14) What are the characteristics of wind dispersal seeds.
Ans. Wind dispersal seeds are light weight and having a tuft of hair or wings. e.g. Cotton, Silk cotton etc.
15) Write the characteristics of water dispersed seed?
Ans. Seeds dispersed by water are light weight and able to float. e. g. Coconut, Lotus.
16) Why some seeds have hooks on it?
Ans. Some seeds have hooks, pointed hair, spines, spikes etc, to be attached to the hairy skin of animals when come in contract with them. By this way seeds can be dispersed by animal.
17) Pitcher plant is grown in soil but still captures insect. Why?
Ans. Pitcher plant grown in the soil which is different of nitrogen. To replenish the nitrogen content of body pitcher plants feed on insect to make up for the lack of nitrogen.
18) What is the function of Calyx?
Ans. Sepals or Calyx are green in colour. It protects the flower when it is a bud.
19) What is the function of Corolla?
Ans. Corolla are bright in colour with sweet scent. So these structures attract insects for pollination.
20) State the function of Androecium?
Ans. Androecium has a sac like structure another hold by thin, thread like filament. Anther bears pollen which is the male reproductive cell.
21) Write down the content of Gynoecium.
Ans. Gynoecium contains Stigma, Style, Ovary and Ovule.
22) What is staminal tube?
Ans. In china rose flower, the carpels are joined and the style runs through the tube formed by the joined stamens which is known as staminal tube.
23) What is inflorescence?
Ans. Cluster of flower and its arrangement on a plant is called inflorescence. It is of two types: Cymose and Racemose.
24) Name some flowers bearing inflorescence?
Ans. Flowers bearing inflorescence are: Banana, Wheat, Mustard, Tuberose, Coriander, Mulberry Gulmohar, Sunflower, Tulsi, Grapes etc.
25)What are the two parts present in a flowering plant?
Ans. A flowering plant has two parts – one is below the ground and another is above the ground. The part below the ground is called root system. The part above the ground is called shoot system.
26)What are the contents of both the system.
Ans. Root system contains root, branches of root & root hairs.
Shoot system contains stem, branches of stem, leaves, flowers, buds & fruits.
27)What is apex of root?
Ans. When main root grows vertically down into the soil then it is broad near the base of the stem and tapers at the tip. This tapering tip of root is called Root apex.
28)How do you classify the plant according to stem structure?
Ans. All plants do not have the same kind of stem. Plants are classified according to the stem structure into three divisions:
- Trees : It has thick, strong stem. eg: Banyan tree, Mango tree.
- Shrubs: It has hard woody stems that are neither thick nor strong as the trunk of tree. eg: Hibiscus, Tulsi etc.
- Herbs : it has soft, green stems so that plants become climber. eg: Mustard, Pumpkin.
29)What is the importance of bearing leaf, bud, flower & fruits in stems?
Ans. The stem bears leaves, buds, flowers & fruits & helps to spread them out so that they can function properly. For example, it helps to spread out the leaves in such a way that they get the maximum possible sunlight and air.
30)What is alternate arrangement of leaves? Give example.
Ans. When only one leaf grows from each node and consecutive leaves are arranged in alternate order. This type of arrangement is known as alternate arrangement. e.g. Sunflower & Chinarose.
31)What is opposite arrangement of leaves? Give example.
Ans. When two leaves grow from each node & are arranged opposite each other, the arrangement is called opposite. e.g. Guava, Prasil.
32)What is whorled arrangement of leaf? Give example.
Ans. When three or more leaves grow from each node forming a circular arrangement or whorl then this type of arrangement is called whorled arrangement. e.g. oleander & davil tree.
33)What is the importance of micropyle in seed?
Ans. Hilum is a location by which seed is attached to the fruit. Right below the hilum is a small pore called micropyle. During fertilization the pollen tube enters the ovule through this pore. Moisture enters the seed through the micropyle.
34)What is the speciality in monocot seed which cannot be found in dicot seed.
Ans. Dicot seed contains radicle or root of embryo & plumule or shoot of embryo. Monocot seed also contains Radicle & Plumule. Beside it one-one protective covering is also present. Protecting covering of Radicle is coleorhiza Protective covering of Plumule is coleoptile.
35)How is a seed germinated?
Ans. Here are the steps of seed germination: –
- Seed absorbs water & swells up.
- Seed coat is ruptured.
- Radicle & Plumule are emerged out of the seed.
- The radicle grows downwards.
- The plumule grows upward.
- Initially cotyledon supplies food to the growing embryo.
- After that radicle develops into root & Plumule develops into stem & leaf.
- Root, absorbs water & minerals.
- Stem & leaves perform photosynthesis.
- Growing seedling will get food by this process, — In this way seed germination occurs.
36)State a small experiment to understand whether a seed is dicot or monocot.
Ans. Some gram, bean, rice, maize & wheat seeds are soaked overnight. After that one seed of each type is taken and placed them on a hard surface. The seeds are pressed a little. If the seeds is splitted into two then it is a dicot seed. If the seed is not splitted then the seed is monocot seed.
37)Give one-one example of epigeal & hypogeal germination.
Ans. Epigeal – Bean; Hypogeal – Pea.