05 Morphology of Flowering Plants

Exercise

Question:

Justify the following statements on the basis of external features: (i) Underground parts of a plant are not always roots. (ii) Flower is a modified shoot.

Answer:

(i) Underground parts of a plant are not always roots.

Explanation: Underground parts of a plant can also be stems, rhizomes, and tubers. These structures all have different functions, but they are not roots. For example, a stem can store food and provide support for the plant, while a rhizome can grow horizontally and enable the plant to spread. Tubers, on the other hand, can store food and provide energy for the plant.

(ii) Flower is a modified shoot.

Explanation: A flower is a modified shoot because it has specialized parts such as sepals, petals, and reproductive organs. These parts are not found in regular shoots, and they are adapted to attract pollinators and ensure successful reproduction. Additionally, flowers are typically brightly colored, which further serves to attract pollinators.

Question:

Define the following terms: (a) Aestivation (b) Placentation (c) Actinomorphic (d) Zygomorphic (e) Superior ovary (f) Perigynous flower (g) Epipetalous stamen

Answer:

(a) Aestivation: The arrangement of sepals, petals, and other floral parts in a flower bud.

(b) Placentation: The arrangement of ovules within the ovary of a flower.

(c) Actinomorphic: Describes a flower that is radially symmetrical.

(d) Zygomorphic: Describes a flower that is bilaterally symmetrical.

(e) Superior ovary: An ovary that is located above the attachment point of the other flower parts.

(f) Perigynous flower: A flower in which the petals, sepals, and stamens are all attached to the top of the ovary.

(g) Epipetalous stamen: A stamen that is attached to the petal of a flower.

Question:

Draw the labelled diagram of the following: i) Gram seed ii) V. S. of maize seed

Answer:

i) Gram Seed

Labeled Diagram:

[Diagram of a Gram Seed with Labels for the Testa, Hilum, Embryo, and Endosperm]

ii) V.S. of Maize Seed

Labeled Diagram:

[Diagram of a Maize Seed with Labels for the Testa, Hilum, Embryo, Endosperm, and Pericarp]

Question:

Describe modifications of stem with suitable examples.

Answer:

Step 1: Understand the concept of stem modification. Stem modification is a process of changing the form of a stem, or the main part of a word, to create a new word. It is a common process used in the formation of many words in the English language.

Step 2: Identify examples of stem modification. Examples of stem modification include adding prefixes and suffixes to words, such as the addition of “-ness” to “happy” to form “happiness” or the addition of “un-” to “happy” to form “unhappy”. Another example is the addition of “-ly” to “quick” to form “quickly”.

Step 3: Explain the process of stem modification. Stem modification is the process of changing the form of a stem, or the main part of a word, to create a new word. It is done by adding prefixes and suffixes to words, or by changing the spelling of the stem. This process is used to create new words with different meanings and to change the tense or part of speech of a word.

Question:

Is Lushkoff a willing worker? Why, then, does he agree to chop wood for Sergei?

Answer:

  1. Lushkoff is a willing worker because he agrees to chop wood for Sergei.
  2. This could be because Sergei asked him to do it, or because Lushkoff wants to help Sergei in some way.
  3. It could also be because Lushkoff wants to prove himself to Sergei, or to gain favor with him.

Question:

Sergei says, “I am happy that my words have taken effect.” Why does he say so? Is he right in saying this?

Answer:

  1. Sergei is likely saying this because he believes that his words have had an influence on someone or something.

  2. It is difficult to determine if he is right in saying this without knowing the context of the situation.

Question:

What reasons does he give to Sergei for his telling lies?

Answer:

  1. First, ask Sergei what reasons he believes the other person has for telling lies.
  2. Listen to Sergei’s response and take note of the reasons he provides.
  3. Ask the other person why they are telling lies, and listen to their response.
  4. Take note of the reasons they provide for their lying.
  5. Compare the reasons Sergei provided with those given by the other person.
  6. Answer the original question by providing the reasons given by the other person for their lying.

Question:

How do the various leaf modifications help plants?

Answer:

  1. Leaf modifications help plants by providing them with different ways to collect sunlight, conserve water, and absorb nutrients.

  2. For example, some plants have waxy or hairy leaves that help to reduce water loss through evaporation. Other plants have modified leaves with spines or thorns that help to deter herbivores from eating them.

  3. Some plants have large, flat leaves that help to maximize the amount of sunlight they can collect. This helps them to photosynthesize more efficiently and produce more energy for the plant.

  4. Other plants have modified leaves that are adapted for different climates. For example, some plants have thick, waxy leaves that help them to conserve water in hot and dry climates. Other plants have thin, small leaves that help them to survive in cold and wet climates.

  5. Finally, some plants have modified leaves that are specialized for nutrient absorption. For example, some plants have modified leaves that are covered in tiny hairs that help to increase the surface area of the leaf and allow them to absorb more nutrients from the soil.

Question:

How is a pinnately compound leaf different from a palmately compound leaf?

Answer:

  1. A pinnately compound leaf is composed of leaflets that are arranged along the central stem in a feather-like pattern.

  2. A palmately compound leaf has leaflets that are attached to a single point at the end of the stem.

  3. The number of leaflets in a pinnately compound leaf can vary, while the number of leaflets in a palmately compound leaf is usually three to seven.

  4. The leaflets of a pinnately compound leaf are typically longer and narrower than those of a palmately compound leaf.

Question:

Describe the various types of placentations found in flowering plants.

Answer:

  1. Placentation is a term used to describe the arrangement of ovules within the ovary of a flowering plant.

  2. There are four main types of placentation: axile, basal, free central, and parietal.

  3. Axile placentation occurs when the ovules are arranged along the central axis of the ovary. This is the most common type of placentation found in flowering plants.

  4. Basal placentation occurs when the ovules are attached to the base of the ovary. This type of placentation is found in plants such as the pea family.

  5. Free central placentation occurs when the ovules are attached to the sides of the ovary and are not attached to the central axis. This type of placentation is found in plants such as the poppy family.

  6. Parietal placentation occurs when the ovules are attached to the walls of the ovary. This type of placentation is found in plants such as the mustard family.

Question:

Explain with suitable examples, the different types of phyllotaxy.

Answer:

Phyllotaxy is the arrangement of leaves on a stem or branch. There are three main types of phyllotaxy: alternate, opposite, and whorled.

  1. Alternate Phyllotaxy: In this type of arrangement, the leaves are arranged alternately along the stem, with each leaf directly opposite to the one above or below it. An example of this would be a maple tree.

  2. Opposite Phyllotaxy: In this type of arrangement, the leaves are arranged in pairs on opposite sides of the stem. An example of this would be a dogwood tree.

  3. Whorled Phyllotaxy: In this type of arrangement, the leaves are arranged in a spiral pattern around the stem. An example of this would be a pine tree.

Question:

Take one flower each of the families Fabaceae and Solanaceae and write its semi-technical description. Also draw their floral diagram after studying them.

Answer:

  1. Gather one flower from each of the families Fabaceae and Solanaceae.

  2. Study the flowers to identify their parts and characteristics.

  3. For the Fabaceae flower, write a semi-technical description that includes the following information: flower color, size, shape, number of petals, and any other distinguishing features.

  4. For the Solanaceae flower, write a semi-technical description that includes the following information: flower color, size, shape, number of petals, and any other distinguishing features.

  5. Draw a floral diagram of each flower, including the parts and characteristics that were identified in steps 3 and 4.

Question:

Differentiate between (a) Racemose and cymose inflorescence (b) Fibrous root and adventitious root (c) Apocarpous and syncarpous ovary

Answer:

(a) Racemose inflorescence is an indeterminate type of inflorescence in which the flowers are borne on an unbranched main axis. The main axis continues to grow and the flowers are borne in acropetal succession. Cymose inflorescence is a determinate type of inflorescence in which the flowers are borne on a branched main axis. The main axis does not continue to grow and the flowers are borne in basipetal succession.

(b) Fibrous roots are the roots that grow from the base of the stem and are thin and thread-like in structure. They are usually found in monocotyledonous plants. Adventitious roots are the roots that grow from any part of the stem or leaves and are thicker and fleshy in structure. They are usually found in dicotyledonous plants.

(c) Apocarpous ovary is an ovary that consists of separate carpels. Each carpel has its own style and stigma. Syncarpous ovary is an ovary that consists of fused carpels. The style and stigma are fused together and form a single structure.

Question:

What is meant by modification of root? What type of modification of root is found in the: (a) Banyan tree (b) Turnip (c) Mangrove trees

Answer:

Answer: Modification of root is the process in which the root of a plant undergoes changes to become specialized for certain functions.

(a) Banyan tree: The roots of the banyan tree are modified to form aerial roots which come out of the branches and penetrate the soil to provide support to the tree.

(b) Turnip: The root of the turnip is modified to form a swollen, edible taproot.

(c) Mangrove trees: The roots of mangrove trees are modified to form pneumatophores which are specialized structures that help the tree to breathe in anaerobic conditions.

01 The Living World

02 Biological Classification

03 Plant Kingdom

04 Animal Kingdom

05 Morphology of Flowering Plants

06 Anatomy of Flowering Plants

07 Structural Organization in Animals

08 Cell

09 Biomolecules

10 Cell Cycle and Cell Division

11 Transport in Plants

12 Mineral Nutrition

13 Photosynthesis in Higher Plants

14 Respiration in Plants

15 Plant Growth and Development

16 Digestion and Absorption

17 Breathing and Exchange of Gases

18 Body Fluids and Circulation

19 Excretory Products and their Elimination

20 Locomotion and Movement

21 Neural Control and Coordination

22 Chemical Control and Integration