1. Racemose and cymose inflorescence:- Racemose Inflorescence:- 1. Younger flowers are present at the tip while older flowers are arranged at the base of this inflorescence. Such an arrangement is called acropetal succession. 2. The main axis in racemose inflorescence continues to grow and produce fRead more
1. Racemose and cymose inflorescence:-
Racemose Inflorescence:-
1. Younger flowers are present at the tip while older flowers are arranged at the base of this inflorescence. Such an arrangement is called acropetal succession.
2. The main axis in racemose inflorescence continues to grow and produce flowers laterally.
Cymose Inflorescence:-
(1) Younger flowers are present at the base of the inflorescence, while older flowers are present at the top. Such an arrangement is called basipetal succession.
(2) The main axis in cymose inflorescence has limited growth, which later terminates into a flower.
(b) Fibrous roots and adventitious roots:-
Fibrous root:-
(1) In monocots, the primary root which develops from the radicle of the seed is short-lived and is replaced by a large number of roots arising from the base of the stem.
(2) It is found in wheat and other cereals
Adventitious root:-
(1) These roots arise from any part of the plant other than the radicle of seeds.
(2) It is found in banyan, Monstera, and other plants.
(c) Apocarpous and syncarpous ovary:-
Apocarpous ovary:-
(1) The flowers with apocarpus ovary have more than one carpel. These carpels are free.
(2) It is found in lotus and rose flowers.
Syncarpous ovary:-
(1) The flowers with syncarpous ovary have more than one carpel. However, these carpels are fused.
(2) It is found in the flowers of tomato and mustard.
(a) Aestivation The term ‘aestivation’ refers to the mode in which sepals or petals are arranged in a floral bud with respect to other floral members. There are four types of aestivation in plants i.e., valvate, twisted, imbricate, and vexillary. (b) Placentation The term ‘placentation’ refers to thRead more
(a) Aestivation
The term ‘aestivation’ refers to the mode in which sepals or petals are arranged in a floral bud with respect to other floral members. There are four types of aestivation in plants i.e., valvate, twisted, imbricate, and vexillary.
(b) Placentation
The term ‘placentation’ refers to the arrangement of ovules within the ovary of a flower. It is primarily of five types, namely marginal, basal, parietal, axile, and free central.
(c) Actinomorphic
Actinomorphic flowers can be divided into two radial halves by any radial plane passing through its centre. Examples of these flowers include chilly and mustard.
(d) Zygomorphic
Zygomorphic flowers are those flowers which can be divided into two similar halves by a single vertical plane. Examples of these flowers include pea and beans.
(e) Superior ovary
Superior ovary flowers are those flowers in which the gynoecium is present at the highest position, while other floral parts are arranged below it. A flower with this arrangement is described as hypogynous. Examples include brinjal and mustard.
(f) Perigynous flower
In perigynous flowers, the gynoecium is present in the centre and the rest of the floral parts are arranged at the rim of the thalamus at the same level. Examples include plum and rose.
(g) Epipetalous Stamen
Epipetalous stamens are stamens attached to the petals. They are found in brinjal.
Phyllotaxy refers to the pattern or arrangement of leaves on the stem or branch of a plant. It is of three types, alternate, opposite, and whorled phyllotaxy. In alternate phyllotaxy, a single leaf arises from the node of a branch. This type of phyllotaxy is observed in the sunflower, mustard, and pRead more
Phyllotaxy refers to the pattern or arrangement of leaves on the stem or branch of a plant. It is of three types, alternate, opposite, and whorled phyllotaxy.
In alternate phyllotaxy, a single leaf arises from the node of a branch. This type of phyllotaxy is observed in the sunflower, mustard, and peepal. Plants with opposite phyllotaxy have two leaves arising from the node in opposite directions. It is found in guava and jamun plants. Plants with whorled phyllotaxy have three or more leaves arising from the node. It is found in Alstonia.
Pinnately Compound Leaf:- 1. The leaflets are attached to the common axis, called rachis. 2. Examples include neem and Cassia fistula( also called golden shower plant) Palmately Compound Leaf:- 1. The leaflets are attached at a common point on the leaf stalk. 2. Examples include silk cotton (Bombax)Read more
Pinnately Compound Leaf:-
1. The leaflets are attached to the common axis, called rachis.
2. Examples include neem and Cassia fistula( also called golden shower plant)
Palmately Compound Leaf:-
1. The leaflets are attached at a common point on the leaf stalk.
2. Examples include silk cotton (Bombax) and Cannabis.
(i) Various parts of plants are modified into underground structures to perform various functions such as stems, leaves, and even fruits. The stems in ginger and banana are underground and swollen due to storage of food. They are called rhizomes. Similarly, corm is an underground stem in Colocasia aRead more
(i) Various parts of plants are modified into underground structures to perform various functions such as stems, leaves, and even fruits.
The stems in ginger and banana are underground and swollen due to storage of food. They are called rhizomes. Similarly, corm is an underground stem in Colocasia and Zamin-khand. The tips of the underground stem in potato become swollen due to the accumulation of food and forms tuber. Tubers bear eyes, which are subtended by a leaf scar. Basal leaves in onions become fleshy because of the accumulation of food. In peanuts, the flower after fertilization gets pushed inside the soil by growing a flower stalk. The formation of fruits and seeds takes place inside the soil.
(ii) During the flowering season, the apical meristem gives rise to the floral meristem. The axis of the stem gets condensed, while the internodes lie near each other. Instead of leaves, various floral appendages arise from the node. Therefore, it can be said that the flower is a modified shoot.
Differentiate between: (a) Racemose and cymose inflorescence (b) Fibrous roots and adventitious roots (c) Apocarpous and syncarpous ovary
1. Racemose and cymose inflorescence:- Racemose Inflorescence:- 1. Younger flowers are present at the tip while older flowers are arranged at the base of this inflorescence. Such an arrangement is called acropetal succession. 2. The main axis in racemose inflorescence continues to grow and produce fRead more
1. Racemose and cymose inflorescence:-
Racemose Inflorescence:-
1. Younger flowers are present at the tip while older flowers are arranged at the base of this inflorescence. Such an arrangement is called acropetal succession.
2. The main axis in racemose inflorescence continues to grow and produce flowers laterally.
Cymose Inflorescence:-
(1) Younger flowers are present at the base of the inflorescence, while older flowers are present at the top. Such an arrangement is called basipetal succession.
(2) The main axis in cymose inflorescence has limited growth, which later terminates into a flower.
(b) Fibrous roots and adventitious roots:-
Fibrous root:-
(1) In monocots, the primary root which develops from the radicle of the seed is short-lived and is replaced by a large number of roots arising from the base of the stem.
(2) It is found in wheat and other cereals
Adventitious root:-
(1) These roots arise from any part of the plant other than the radicle of seeds.
(2) It is found in banyan, Monstera, and other plants.
(c) Apocarpous and syncarpous ovary:-
Apocarpous ovary:-
(1) The flowers with apocarpus ovary have more than one carpel. These carpels are free.
(2) It is found in lotus and rose flowers.
Syncarpous ovary:-
(1) The flowers with syncarpous ovary have more than one carpel. However, these carpels are fused.
(2) It is found in the flowers of tomato and mustard.
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Define the following terms: (a) Aestivation (b) Placentation (c) Actinomorphic (d) Zygomorphic (e) Superior ovary (f) Perigynous flower (g) Epipetalous Stamen
(a) Aestivation The term ‘aestivation’ refers to the mode in which sepals or petals are arranged in a floral bud with respect to other floral members. There are four types of aestivation in plants i.e., valvate, twisted, imbricate, and vexillary. (b) Placentation The term ‘placentation’ refers to thRead more
(a) Aestivation
The term ‘aestivation’ refers to the mode in which sepals or petals are arranged in a floral bud with respect to other floral members. There are four types of aestivation in plants i.e., valvate, twisted, imbricate, and vexillary.
(b) Placentation
The term ‘placentation’ refers to the arrangement of ovules within the ovary of a flower. It is primarily of five types, namely marginal, basal, parietal, axile, and free central.
(c) Actinomorphic
Actinomorphic flowers can be divided into two radial halves by any radial plane passing through its centre. Examples of these flowers include chilly and mustard.
(d) Zygomorphic
Zygomorphic flowers are those flowers which can be divided into two similar halves by a single vertical plane. Examples of these flowers include pea and beans.
(e) Superior ovary
Superior ovary flowers are those flowers in which the gynoecium is present at the highest position, while other floral parts are arranged below it. A flower with this arrangement is described as hypogynous. Examples include brinjal and mustard.
(f) Perigynous flower
In perigynous flowers, the gynoecium is present in the centre and the rest of the floral parts are arranged at the rim of the thalamus at the same level. Examples include plum and rose.
(g) Epipetalous Stamen
Epipetalous stamens are stamens attached to the petals. They are found in brinjal.
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Explain with suitable examples the different types of phyllotaxy?
Phyllotaxy refers to the pattern or arrangement of leaves on the stem or branch of a plant. It is of three types, alternate, opposite, and whorled phyllotaxy. In alternate phyllotaxy, a single leaf arises from the node of a branch. This type of phyllotaxy is observed in the sunflower, mustard, and pRead more
Phyllotaxy refers to the pattern or arrangement of leaves on the stem or branch of a plant. It is of three types, alternate, opposite, and whorled phyllotaxy.
In alternate phyllotaxy, a single leaf arises from the node of a branch. This type of phyllotaxy is observed in the sunflower, mustard, and peepal. Plants with opposite phyllotaxy have two leaves arising from the node in opposite directions. It is found in guava and jamun plants. Plants with whorled phyllotaxy have three or more leaves arising from the node. It is found in Alstonia.
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See lesshttps://www.tiwariacademy.com/ncert-solutions/class-11/biology/chapter-5/
How is pinnately compound leaf different from palmately compound leaf?
Pinnately Compound Leaf:- 1. The leaflets are attached to the common axis, called rachis. 2. Examples include neem and Cassia fistula( also called golden shower plant) Palmately Compound Leaf:- 1. The leaflets are attached at a common point on the leaf stalk. 2. Examples include silk cotton (Bombax)Read more
Pinnately Compound Leaf:-
1. The leaflets are attached to the common axis, called rachis.
2. Examples include neem and Cassia fistula( also called golden shower plant)
Palmately Compound Leaf:-
1. The leaflets are attached at a common point on the leaf stalk.
2. Examples include silk cotton (Bombax) and Cannabis.
For more answers visit to website:
See lesshttps://www.tiwariacademy.com/ncert-solutions/class-11/biology/chapter-5/
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
(i) Various parts of plants are modified into underground structures to perform various functions such as stems, leaves, and even fruits. The stems in ginger and banana are underground and swollen due to storage of food. They are called rhizomes. Similarly, corm is an underground stem in Colocasia aRead more
(i) Various parts of plants are modified into underground structures to perform various functions such as stems, leaves, and even fruits.
The stems in ginger and banana are underground and swollen due to storage of food. They are called rhizomes. Similarly, corm is an underground stem in Colocasia and Zamin-khand. The tips of the underground stem in potato become swollen due to the accumulation of food and forms tuber. Tubers bear eyes, which are subtended by a leaf scar. Basal leaves in onions become fleshy because of the accumulation of food. In peanuts, the flower after fertilization gets pushed inside the soil by growing a flower stalk. The formation of fruits and seeds takes place inside the soil.
(ii) During the flowering season, the apical meristem gives rise to the floral meristem. The axis of the stem gets condensed, while the internodes lie near each other. Instead of leaves, various floral appendages arise from the node. Therefore, it can be said that the flower is a modified shoot.
For more answers visit to website:
See lesshttps://www.tiwariacademy.com/ncert-solutions/class-11/biology/chapter-5/