Chap 2 Flowers Part 2-Pollination fertilisation

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Questions and Answers

What part of the flower forms the fleshy part of false fruits like apple and strawberry?

Ovary

Petals

Sepals

Thalamus (correct)

Which of the following is not a function of fruit?

Protecting seeds from harsh climatic conditions

Facilitating fertilization (correct)

Assisting in the dispersal of seeds

Storing food

Which part of the seed develops into the root system of the plant?

Plumule

Cotyledons

Radicle (correct)

Seed coat

Which type of fruits are Almond, Walnut, and Pistachio classified as before they are dried for use?

Fleshy fruits Signup and view all the answers

What is fusion of male and female gametes known as?

Fertilization Signup and view all the answers

Which of the following statements is true about seeds?

They can be fertilized ovules. Signup and view all the answers

Which characteristic is commonly found in insect-pollinated flowers?

Bright colours like red, orange, or yellow Signup and view all the answers

What is the primary function of sticky pollen grains in insect-pollinated flowers?

To attach to insects Signup and view all the answers

Which of these animals does NOT help in cross-pollination?

Snakes Signup and view all the answers

What structure grows down through the style to enter the ovary during fertilisation?

Pollen tube Signup and view all the answers

In the process of fertilisation, what does the male gamete fuse with?

Female gamete or egg Signup and view all the answers

Which of the following flowers would be best to study insect-pollination?

China rose Signup and view all the answers

What is the primary purpose of seed dispersal?

To ensure wide distribution of seeds Signup and view all the answers

Which of these seeds is known to be dispersed by wind?

Poppy Signup and view all the answers

What characteristic is common in seeds dispersed by water?

They have a spongy or fibrous outer coat Signup and view all the answers

Where does the radicle grow during seed germination?

Into the soil Signup and view all the answers

Which of the following seeds has a special structure like hooks, spines, or bristles for dispersal by animals?

Xanthium Signup and view all the answers

What is a characteristic feature of dicotyledonous seeds?

Absence of endosperm Signup and view all the answers

Which of the following is true for monocotyledonous seeds?

Endosperm stores food Signup and view all the answers

What statement is correct about a maize seed?

Endosperm is present Signup and view all the answers

Which plant's seeds are examples of dicotyledonous seeds?

Pea Signup and view all the answers

In the study of the structure of dicot and monocot seeds, what is identified after splitting open the cotyledons?

Plumule and radicle Signup and view all the answers

What is the function of cotyledons in dicotyledonous seeds?

Store food Signup and view all the answers

Which part of the fruit corresponds to the outer thin covering?

Epicarp Signup and view all the answers

What happens to the cotyledons during hypogeal germination?

They remain under the soil and do not form leaves. Signup and view all the answers

Which of the following is an example of a plant that undergoes hypogeal germination?

Maize Signup and view all the answers

In dry fruits, what is usually the edible part?

Seeds Signup and view all the answers

Why is moisture essential for seed germination?

It activates the embryo to grow. Signup and view all the answers

What happens to the ovules after fertilization in the context of fruit formation?

They develop into seeds Signup and view all the answers

During epigeal germination in bean seeds, what should be done with the seeds before planting them?

Soak them in water overnight. Signup and view all the answers

Which layer of the pericarp is described as the sweet, fleshy middle layer?

Mesocarp Signup and view all the answers

What is one of the reasons seeds planted deeper in the soil fail to germinate?

Lack of oxygen Signup and view all the answers

Which of the following fruits is classified as a fleshy fruit?

Raspberries Signup and view all the answers

Which of the following best describes the aim of the activity involving hypogeal germination?

To study hypogeal germination in maize grains. Signup and view all the answers

What typically happens to sepals after fruit formation in tomatoes, brinjals, and lady's fingers?

They do not fall off Signup and view all the answers

What is the main conclusion derived from Activity 10?

Water and oxygen together are necessary for germination. Signup and view all the answers

Which seed in the activity fails to germinate due to lack of water?

Seed A Signup and view all the answers

Which factor is NOT tested in Activity 10 to determine its necessity for germination?

Light Signup and view all the answers

What happens to Seed B in the procedure?

It germinates normally. Signup and view all the answers

What is the reason for Seed C not germinating according to the observation?

Seed C did not get enough oxygen. Signup and view all the answers

Which part of the observation reflects the importance of oxygen in germination?

Seed C being swollen but not germinating Signup and view all the answers

What is the correct term for the process of a seed growing into a young plant?

Germination Signup and view all the answers

What should Seed A's position be during the activity?

Above the water level Signup and view all the answers

During the experiment, how much of the beaker should be filled with water?

Three-quarters Signup and view all the answers

Study Notes

Characteristics of Insect-Pollinated Flowers

Insect-pollinated flowers have bright colors like red, orange, or yellow to attract insects.
They produce nectar and have a sweet smell to attract insects at night.
They have sticky pollen grains and stigma.

Pollination by Animals

Animals like birds, mammals, and even humans help in cross-pollination.

Fertilisation

After a pollen grain reaches the stigma of the same kind of flower, it germinates into a pollen tube.
The pollen tube grows down through the style and enters the ovary to reach the ovule.
The pollen tube releases male cells or male gametes, which fuse with the female gamete, producing a zygote.
Fertilization is the fusion of male and female cells or gametes.

Formation of Fruit

The ovary remains attached to the stalk of the flower and grows into a fruit.
The ovules in the ovary develop into seeds.
The wall of the ovary develops into the fruit wall.
The other parts of the flower, like sepals, petals, fall off.

Parts of Fruits

A fruit is a ripened ovary, consisting of pericarp (fruit wall) and seeds.
Pericarp consists of epicarp, mesocarp, and endocarp.

Dry Fruits and Fleshy Fruits

In dry fruits, the pericarp is dry and non-edible, and the edible part is the seed.
In fleshy fruits, the pericarp or some of its parts are soft and pulpy.

Seeds

A seed is a fertilized ovule.
It develops after fertilization and marks the beginning of a new generation.
Seeds are always enclosed in fruits.
A fruit may have one seed or many seeds.

Parts of Seeds

A seed has three main parts: seed coat, embryo, and endosperm.
Seed coat is the protective outer covering of the seed.
Embryo is the baby plant in an inactive stage, consisting of radicle, plumule, and cotyledons.
Endosperm is the food store.

Dispersal of Fruits and Seeds

Distribution of fruits and seeds away from the parent plant is called dispersal.
Dispersal helps in the survival of a large number of seedlings under favorable conditions.

Agents of Seed Dispersal

Wind, water, and animals help in dispersal of seeds to distant places.
Seeds dispersed by wind are small and light in weight.
Seeds dispersed by water have a spongy or fibrous outer coat.
Seeds dispersed by animals have hooks, spines, or bristles to attach to the skin of animals or clothes of human beings.

Seed Germination

Seed germination is the process by which the dormant or inactive embryo in the seed becomes active and grows into a seedling.
Germination begins when the seed swells up by taking water, and the process is called imbibition.
The seed coat ruptures, and the radicle grows down into the soil, forming the root system.
The plumule grows upward in the air, develops leaves, and forms the shoot of the young plant.

Types of Seed Germination

There are two types of germination: epigeal and hypogeal.
In epigeal germination, the cotyledons come out of the soil, become green, and form the first leaves of the seedling.
In hypogeal germination, the cotyledons remain under the soil and do not form leaves.

Conditions Required for Seed Germination

The mature seeds germinate only on receiving suitable conditions of moisture, air, and warmth.
Moisture is essential for seed germination, as it softens the seed coat, activates the embryo, and dissolves stored food.
Oxygen is necessary for seed germination, as it provides energy to the growing embryo.
Temperature also plays a role in seed germination, as it affects the rate of germination.

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Description

Learn about the features of flowers that are pollinated by insects, including their bright colors, nectar production, and sticky pollen grains. Study the process of pollination by observing insects in a garden.