A flower that does not have a stalk and is directly attached to the stem is called a sessile flower.
Definitions [7]
Definition: Variation
The differences in the DNA copies produced during reproduction, which lead to slight or significant changes between organisms, are called variations.
Definition: Reproduction
The biological process by which organisms produce new individuals of their own kind is called reproduction.
Definition: Unisexual Flower
A flower that has only one reproductive whorl (either androecium or gynoecium) is called a unisexual flower.
- If it has only androecium: male flower
- If it has only gynoecium: female flower
Example: Papaya
Definition: Pedicellate Flower
A flower that has a stalk called pedicel for support is called a pedicellate flower.
Definition: Sessile Flower
Definition: Bisexual Flower
A flower that has both androecium (male part) and gynoecium (female part) in the same flower is called a bisexual flower.
Example: Hibiscus
Define.
Inflorescence
A specialised axis or branch over which flowers are produced or borne in definite manner is known as inflorescence.
Key Points
Key Points: DNA Copying and Variation in Reproduction
- Reproduction is the process through which organisms produce new individuals that look similar to themselves.
- The DNA in the nucleus carries instructions for body design and is copied during reproduction.
- DNA copying is not always perfect, and small changes (variations) may occur.
- These variations make offspring slightly different from parents and are important for evolution.
- Variations help species survive in changing environments and ensure the stability of populations over time.
Key Points: Sexual Reproduction in Plants
- Flower is the main reproductive organ in plants, made up of four whorls—calyx, corolla, androecium, and gynoecium.
- Essential whorls: Androecium (male) and Gynoecium (female);
Accessory whorls: Calyx (sepals) and Corolla (petals). - Bisexual flowers have both androecium and gynoecium (e.g., Hibiscus);
Unisexual flowers have only one (e.g., Papaya). - Gynoecium contains carpels with ovary, style, and stigma;
Ovary has ovules, which form the embryo sac by meiosis.
Important Questions [49]
- A Student Was Asked to Observe and Identify the Various Parts of an Embryo of a Red Kidney Bean Seed. He Identified the Parts and Listed Them as Under
- Name the Parts A, B and C Shown in the Diagram and Write Their Functions.
- Name the Parts Labelled as A, B, C and D in the Diagram Given Below:-
- What is pollination?
- How does fertilisation occur in flowers? Name the parts of the flower that develop into (i) seed, and (ii) fruit after fertilisation.
- In the following diagram showing the structure of embryo of a dicot seed, what are the parts marked I, II and III sequentially?
- (i) Name the part marked 'A' in the diagram. (ii) How dose 'A' reachese part 'B'? (iii) State the importance of the part 'C'. (iv) What happens to the part marked 'D' after fertilisation is over?
- A Student While Observing an Embryo of a Pea Seed in the Laboratory Listed Various Parts of the Embryo as Given Below
- Name the Parts A, B and C Shown in the Following Diagram and State One Function of Each.
- A Student Has to Perform the Experiment "To Identify the Different Parts of an Embryo of a Dicot Seed." Select from the Following an Appropriate Group of Seeds
- State significance of pollination.
- Name and differentiate between the two modes of pollination in flowering plants.
- A Student Identified the Various Parts of an Embryo of a Gram Seed and Listed Them as Given Below
- Name the Parts Labelled as A, B, C and D in the Diagram Given Below
- "The Chromosomal Number of the Sexually Producing Parents and Their Offspring is the Same." Justify this Statement.
- Give one example of a unisexual flower.
- Mention the changes a flower undergoes after fertilisation.
- You Are Asked by Your Teacher to Study the Different Parts of an Embryo of a Gram Seed. Given Below Are the Steps to Be Followed for the Experiment
- Write the Names of Those Parts of a Flower Which Serve the Same Function as the Following Do in the Animals
- State the Function of Flowers in the Flowering Plants.
- Explain the Term 'Fertilisation'.
- Write One Main Difference Between Asexual and Sexual Mode of Reproduction. Which Species is Likely to Have Comparatively Better Chances of Survival
- Give One Example Each of Unisexual and Bisexual Flowers. Differentiate Between the Two Types of Pollination that Occur in Flowers.
- You Have to Perform the Experiment, "To Identify the Different Parts of an Embryo of a Gram Seed." Describe the Procedure that You Would Follow.
- The students of a class were asked by the teacher to study the different parts of an embryo of an angiosperm. Given below are the essential steps for the experiment :
- Draw a diagram of the longitudinal section of a flower exhibiting germination of pollen on stigma and label (i) ovary, (ii) male germ-cell, (iii) female germ-cell and (iv) ovule on it.
- Identify A, B, C and D in the Given Diagram and Write Their Names.
- A Student is Asked to Study the Different Parts of an Embryo of Pea Seeds. Given Below Are the Essential Steps for the Experiment
- (A) Identify A, B and C in the Given Diagram and Write Their Functions. (5) (B) Mention the Role of Gamete and Zygote in Sexually Reproducing Organisms.
- In the Figure, the Parts Marked A, B and C Are Sequentially:
- “Cell Division is a Type of Reproduction in Unicellular Organism.” Justify.
- Draw a Diagram of a Pistil Showing Pollen Tube Growth into the Ovule and Label the Following: Pollen Grain, Male Gamete, Female Gamete, Ovary.
- Distinguish between unisexual and bisexual flowers giving one example of each. Draw a diagram showing process of germination of pollen grains on stigma and label the following parts:
- Draw a Diagram of the Longitudinal Section of a Flower and Label on It Sepal, Petal, Ovary and Stigma.
- Write the Names of Male and Female Reproductive Parts of a Flower.
- What is Phototropism?
- Describe an Activity to Demonstrate Phototropism.
- List any two differences between pollination and fertilization.
- Answer the Following Question. How Does Suitable Pollination Lead to Fertilization?
- A Student is Observing the Temporary Mount of a Leaf Peel Under a Microscope. Draw Labelled Diagram of the Structure of Stomata as Seen Under the Microscope
- Differentiate between self-pollination and cross-pollination.
- Answer the Following Question. List Two Agents of Pollination?
- Give reason for the following:Fertilization cannot take place in flowers if pollination does not occur.
- Name the reproductive parts of an angiosperm. Where are these parts located? Explain the structure of its male reproductive part.
- What is puberty?
- In flowering plants, the pollen grains are transferred to stigma by pollination but the female germ cells are present in the ovary.
- Consider the following three flowers namely X, Y and Z. Which flower(s) would develop into a fruit? Flower X Flower Y Flower Z
- Explain the post fertilization changes that occur in the ovary of a flower.
- Given below is a diagram of a germinating seed. Label the parts that: gives rise to future shoot. gives rise to future root system. stores food.
