Morphology of Flowering Plants
What to remember
- Tap roots arise from the radicle and are typical of dicots; fibrous roots are typical of monocots; adventitious roots arise from parts of the plant other than the radicle.
- Flower position of the ovary decides the type: hypogynous (superior ovary), perigynous (half inferior), epigynous (inferior ovary).
- Placentation types are marginal, axile, parietal, free central and basal; aestivation types are valvate, twisted, imbricate and vexillary.
- Fabaceae has a legume and a papilionaceous corolla, Solanaceae has a berry or capsule and epipetalous stamens, and Liliaceae has six tepals and a trilocular ovary.
The root
The root is the underground, non-green part of the plant that develops from the radicle of the embryo. It anchors the plant and absorbs water and minerals.
There are three kinds of root systems.
| Type | Origin | Found in | Example |
|---|---|---|---|
| Tap root system | Primary root, direct elongation of the radicle, with lateral branches | Dicots | Mustard, gram |
| Fibrous root system | Primary root is short-lived and is replaced by many roots from the base of the stem | Monocots | Wheat, rice |
| Adventitious roots | From parts other than the radicle, such as stem or leaves | Grass, Monstera, banyan | Banyan prop roots |
Regions of the root, from the tip upwards:
- Root cap: a thimble-like cover that protects the tender apex as the root grows through soil.
- Region of meristematic activity: cells are small, thin-walled and dividing, with dense cytoplasm.
- Region of elongation: cells are elongating and enlarging, which causes growth in length.
- Region of maturation: cells differentiate into the various tissues. Root hairs, which absorb water and minerals, arise here as fine outgrowths of epidermal cells.
Modifications of roots:
| Modification | Function | Example |
|---|---|---|
| Storage roots | Store food; tap roots become swollen | Carrot, turnip |
| Storage adventitious roots | Store food | Sweet potato |
| Prop roots | Hang from branches and support the tree | Banyan |
| Stilt roots | Grow obliquely from the lower nodes of the stem and support it | Maize, sugarcane |
| Pneumatophores | Grow upward out of the soil to take in air for respiration | Rhizophora (mangrove plants) |
The stem
The stem develops from the plumule and bears nodes and internodes. It has buds, flowers and fruits. It is usually green when young and later becomes woody and dark brown. Its main functions are to spread branches, bear leaves, flowers and fruits, and to conduct water, minerals and photosynthates. Some stems store food, give support, protect the plant or help in vegetative propagation.
Modifications of the stem:
- Underground stems store food and help in perennation (surviving unfavourable seasons) and vegetative propagation. Examples are potato, ginger, turmeric and zaminkand (Amorphophallus), and colocasia.
- Stem tendrils are slender and spirally coiled, arise from axillary buds, and help plants climb. Examples are watermelon, grapes and cucumber.
- Thorns are hard, pointed structures that arise from axillary buds and protect the plant from animals. Examples are Citrus and Bougainvillea.
- Phylloclades are flattened or fleshy green stems that carry out photosynthesis, while leaves are reduced to spines. Example: Opuntia.
- Weak stems of plants that spread over the ground:
| Type | Description | Example |
|---|---|---|
| Runner | Slender lateral branch that spreads on the ground and roots at nodes | Grass |
| Stolon | Lateral branch that arises from the base of the main axis, grows aerially, then bends to touch the ground and roots | Mint, jasmine |
| Offset | Short, thick lateral branch in aquatic plants | Pistia, Eichhornia |
| Sucker | Lateral branch that arises from the basal underground part of the main stem, grows horizontally, then upward | Banana, pineapple, chrysanthemum |
The leaf
The leaf is a lateral, flattened structure borne on the stem at a node. It has an axillary bud in its axil. It is the main organ of photosynthesis.
A typical leaf has three parts:
| Part | Description |
|---|---|
| Leaf base | Attaches the leaf to the stem and may bear two small leaf-like structures called stipules. In monocots the base expands into a sheath that covers the stem. In leguminous plants it is swollen and called the pulvinus. |
| Petiole | Stalk that holds the lamina to light. |
| Lamina (leaf blade) | The green expanded part with veins and veinlets. The middle prominent vein is the midrib. |
Venation is the arrangement of veins and veinlets in the lamina. Reticulate venation (a network) is typical of dicot leaves. Parallel venation is typical of monocot leaves.
A leaf is simple when the lamina is entire or incised but the incisions do not reach the midrib. A leaf is compound when the incisions reach the midrib or the base, breaking the lamina into leaflets. A bud is present in the axil of the petiole of a compound leaf but not in the axils of its leaflets.
- Pinnately compound leaf: leaflets are present on a common axis, the rachis, which represents the midrib. Example: neem.
- Palmately compound leaf: leaflets are attached at a common point, the tip of the petiole. Example: silk cotton.
Phyllotaxy is the pattern of arrangement of leaves on the stem.
| Type | Arrangement | Example |
|---|---|---|
| Alternate | A single leaf at each node | China rose, mustard, sunflower |
| Opposite | A pair of leaves at each node, opposite to each other | Calotropis, guava |
| Whorled | More than two leaves at a node, forming a whorl | Alstonia |
Modifications of leaves: tendrils (pea), spines (cactus), fleshy leaves that store food (onion, garlic), and insect-trapping leaves (pitcher of Nepenthes, bladder of Utricularia). In some plants such as Australian acacia the leaves are small and short-lived, and the petioles expand, become green and make food.
The inflorescence
The inflorescence is the arrangement of flowers on the floral axis. It is of two main types.
| Feature | Racemose | Cymose |
|---|---|---|
| Main axis | Continues to grow | Ends in a flower, so growth is limited |
| Order of flowers | Acropetal: younger flowers at the tip, older at the base | Basipetal: older flowers at the tip, younger at the base |
The flower
The flower is the reproductive unit of an angiosperm. A typical flower has four whorls: calyx, corolla, androecium and gynoecium. A flower with both androecium and gynoecium is bisexual. A flower with only one of them is unisexual.
Symmetry: actinomorphic (radial symmetry, such as mustard, datura, chilli), zygomorphic (bilateral symmetry, such as pea, gulmohur, bean, Cassia) and asymmetric (cannot be divided into equal halves, such as canna). Flowers may be trimerous, tetramerous or pentamerous depending on whether floral appendages are in threes, fours or fives. A flower with a bract is bracteate. One without a bract is ebracteate.
Position of the ovary on the thalamus:
| Type | Ovary position | Other whorls | Example |
|---|---|---|---|
| Hypogynous | Superior | Inserted below the ovary | Mustard, China rose, brinjal |
| Perigynous | Half inferior | At the same level as the ovary | Plum, rose, peach |
| Epigynous | Inferior | Arise above the ovary | Guava, cucumber, ray florets of sunflower |
Calyx is the outermost whorl of sepals. It may be gamosepalous (sepals united) or polysepalous (free). Corolla is the whorl of petals, usually coloured to attract insects. It may be gamopetalous (united) or polypetalous (free).
Aestivation is the mode of arrangement of sepals or petals in a floral bud with respect to the other members of the same whorl.
| Type | Description | Example |
|---|---|---|
| Valvate | Margins touch one another without overlapping | Calotropis |
| Twisted | One margin overlaps the next in a regular direction | China rose, lady's finger, cotton |
| Imbricate | Margins overlap irregularly | Cassia, gulmohur |
| Vexillary | The large posterior petal (standard) overlaps the two lateral wings, which overlap the two smallest anterior petals (keel) | Pea, bean |
Androecium is made of stamens, each with a filament and an anther. Stamens may be united. They are epipetalous when attached to petals (brinjal) and epiphyllous when attached to perianth (lily). Stamens may be monadelphous (one bundle, China rose), diadelphous (two bundles, pea) or polyadelphous (more than two bundles, citrus).
Gynoecium is made of one or more carpels, each with an ovary, style and stigma. When carpels are free the gynoecium is apocarpous (lotus, rose). When carpels are fused it is syncarpous (mustard, tomato). After fertilisation the ovules develop into seeds and the ovary into a fruit.
Placentation is the arrangement of ovules within the ovary.
| Type | Arrangement | Example |
|---|---|---|
| Marginal | Placenta forms a ridge along the ventral suture of a one-chambered ovary | Pea |
| Axile | Placenta is axial and ovary is multilocular | China rose, tomato, lemon |
| Parietal | Ovules develop on the inner wall of a one-chambered ovary | Mustard, Argemone |
| Free central | Ovules borne on the central axis without septa | Dianthus, primrose |
| Basal | Placenta at the base of a one-chambered ovary with a single ovule | Sunflower, marigold |
The fruit and the seed
The fruit is a mature, ripened ovary developed after fertilisation. If a fruit develops without fertilisation it is parthenocarpic. Banana is an example. The fruit wall is the pericarp, which may be dry or fleshy. In fleshy fruits it has three layers: the outer epicarp, the middle mesocarp and the inner endocarp. In mango (a drupe) the mesocarp is fleshy and edible and the endocarp is stony. In coconut the mesocarp is fibrous.
Dicot seed (for example gram or bean): the seed coat has an outer testa and an inner tegmen. The hilum is the scar where the seed was attached to the fruit. The micropyle is a small pore above the hilum. The embryo has an embryonal axis and two cotyledons. The cotyledons store food in non-endospermic seeds such as bean. Seeds with endosperm are endospermic, such as castor.
Monocot seed (for example maize grain): the seed coat is membranous and fused with the fruit wall. The endosperm is bulky and stores food. A proteinaceous layer called the aleurone layer separates the endosperm from the embryo. The embryo is small and lies in a groove at one end. It has one large shield-shaped cotyledon, the scutellum, and a short axis with a plumule and a radicle. The plumule is enclosed by the coleoptile. The radicle is enclosed by the coleorhiza.
Describing a flowering plant
A plant is described in the order of habit, vegetative parts (root, stem, leaves), then floral parts, then the floral diagram and floral formula. The floral formula uses these symbols:
| Symbol | Meaning |
|---|---|
| Br | Bracteate |
| ⊕ | Actinomorphic flower |
| % | Zygomorphic flower |
| ⚥ | Bisexual flower |
| K | Calyx |
| C | Corolla |
| P | Perianth (tepals) |
| A | Androecium |
| G | Gynoecium; a line below G means superior ovary, a line above means inferior ovary |
| ( ) | Fusion of members |
| Line joining parts | Adhesion, for example epipetalous stamens |
A floral diagram shows the number of members and their arrangement and fusion, with the mother axis at the top and the bracts below.
Some important families
| Feature | Fabaceae | Solanaceae | Liliaceae |
|---|---|---|---|
| Class | Dicot | Dicot | Monocot |
| Habit | Herbs, shrubs, trees; root nodules | Herbs, shrubs, small trees | Perennial herbs with bulbs, corms or rhizomes |
| Leaves | Alternate, pinnately compound or simple, pulvinate base, stipulate, reticulate | Alternate, simple, exstipulate, reticulate | Mostly basal, linear, parallel venation |
| Flower | Bisexual, zygomorphic | Bisexual, actinomorphic | Bisexual, actinomorphic |
| Calyx or perianth | Five sepals, gamosepalous, imbricate | Five sepals, united, persistent, valvate | Six tepals (3 + 3), often united, valvate |
| Corolla | Five petals, papilionaceous: standard, two wings, two keels; vexillary | Five petals, united, valvate | Part of perianth |
| Androecium | Ten stamens, diadelphous | Five stamens, epipetalous | Six stamens (3 + 3), epiphyllous |
| Gynoecium | Monocarpellary, unilocular, superior ovary, many ovules | Bicarpellary, syncarpous, bilocular, superior, obliquely placed, axile | Tricarpellary, syncarpous, trilocular, superior, axile |
| Fruit and seed | Legume; non-endospermic seeds | Berry or capsule; endospermous seeds | Capsule, rarely berry; endospermous seeds |
| Floral formula | % ⚥ K(5) C1+2+(2) A(9)+1 G1 | ⊕ ⚥ K(5) C(5) A5 G(2) | Br ⊕ ⚥ P(3+3) A3+3 G(3) |
Economic importance:
- Fabaceae: pulses (gram, arhar, sem, moong, soyabean), edible oil (soyabean, groundnut), dye (indigofera), fibre (sunhemp), ornamentals (lupin, sweet pea) and medicine (muliathi).
- Solanaceae: food plants (potato, tomato, brinjal, chilli), medicinal plants (belladonna, ashwagandha), tobacco and ornamental petunia.
- Liliaceae: ornamentals (tulip, Gloriosa), medicinal (Aloe), vegetable (Asparagus) and colchicine from Colchicum autumnale.
NEET traps
- Prop roots hang from branches (banyan). Stilt roots grow obliquely from lower nodes (maize, sugarcane).
- Sweet potato is a modified root. Potato, ginger and turmeric are modified stems.
- Opuntia has a flattened stem (phylloclade). Its leaves are reduced to spines. Citrus thorns arise from axillary buds, not leaves.
- Pea tendrils are modified leaves. Watermelon and grape tendrils are modified stems.
- Racemose is acropetal with a continuing main axis. Cymose is basipetal with a terminating main axis.
- Guava and cucumber are epigynous. Rose, plum and peach are perigynous. Mustard and China rose are hypogynous.
- Mustard has parietal placentation. China rose, tomato and lemon have axile. Sunflower has basal. Pea has marginal.
- Vexillary aestivation is in pea. Imbricate is in Cassia and gulmohur. Twisted is in China rose and cotton. Valvate is in Calotropis.
- Pea stamens are diadelphous (9 + 1). China rose stamens are monadelphous. Citrus stamens are polyadelphous.
- Scutellum is the single cotyledon of maize. Coleoptile covers the plumule. Coleorhiza covers the radicle.
One-liners
- Fibrous roots are present in wheat and rice.
- The region of maturation bears root hairs.
- Pneumatophores are present in Rhizophora.
- Offsets are present in Pistia and Eichhornia.
- Sucker is the stem modification of banana and pineapple.
- Neem has pinnately compound leaves.
- Silk cotton has palmately compound leaves.
- Alstonia shows whorled phyllotaxy.
- Pulvinus is the swollen leaf base of leguminous plants.
- Calotropis shows valvate aestivation and opposite phyllotaxy.
- Lotus and rose have apocarpous gynoecium.
- Banana is a parthenocarpic fruit.
- The edible part of mango is the mesocarp.
- The fruit of Fabaceae is a legume.
- Colchicine is obtained from Colchicum autumnale of Liliaceae.
Practice questions
Which type of root system develops by the direct elongation of the radicle?
- Prop root system
- Tap root system
- Fibrous root system
- Stilt root system
Answer
B. Tap root system
The primary root formed from the radicle is the tap root; it bears lateral branches.
Root hairs are found in which region of the root?
- Region of elongation
- Region of meristematic activity
- Root cap
- Region of maturation
Answer
D. Region of maturation
Root hairs arise from epidermal cells in the region of maturation and absorb water and minerals.
Pneumatophores are the modified roots seen in
- Banyan
- Maize
- Rhizophora
- Carrot
Answer
C. Rhizophora
Rhizophora (a mangrove plant) has roots that grow upward out of the soil to take in air.
Stilt roots that support the plant arise from the lower nodes of the stem in
- banyan only
- maize and sugarcane
- Rhizophora and carrot
- turnip and sweet potato
Answer
B. maize and sugarcane
Maize and sugarcane have stilt roots; banyan has prop roots from branches.
Which of the following is an underground modified stem used for storage?
- Ginger
- Turnip
- Carrot
- Sweet potato
Answer
A. Ginger
Ginger is a rhizome (stem). Sweet potato, carrot and turnip are modified roots.
In leguminous plants the leaf base is swollen and is called
- pulvinus
- stipule
- leaf sheath
- rachis
Answer
A. pulvinus
A swollen leaf base is called the pulvinus; in monocots the base forms a sheath.
A pinnately compound leaf is seen in
- silk cotton
- mustard
- China rose
- neem
Answer
D. neem
Neem has leaflets on a common axis (rachis). Silk cotton is palmately compound.
Whorled phyllotaxy, with more than two leaves at a node, is seen in
- mustard
- China rose
- Alstonia
- guava
Answer
C. Alstonia
Alstonia has whorled leaves; mustard and China rose are alternate; guava is opposite.
Which statement describes a cymose inflorescence?
- The main axis grows continuously and the flowers open in basipetal order
- The main axis ends in a flower and the flowers open in basipetal order
- The main axis grows continuously and the flowers open in acropetal order
- The main axis ends in a flower and the flowers open in acropetal order
Answer
B. The main axis ends in a flower and the flowers open in basipetal order
In cymose inflorescence growth is limited and the youngest flowers are at the base.
Vexillary aestivation is seen in
- China rose
- Calotropis
- pea
- gulmohur
Answer
C. pea
Pea has a standard, two wings and a keel (vexillary). China rose is twisted, Calotropis valvate, gulmohur imbricate.
Mustard shows which type of placentation?
- Marginal
- Basal
- Axile
- Parietal
Answer
D. Parietal
In mustard the ovules develop on the inner wall of a one-chambered ovary.
Free central placentation is found in
- Dianthus
- pea
- lemon
- sunflower
Answer
A. Dianthus
Dianthus and primrose have ovules on a central axis without septa.
Which of the following is a parthenocarpic fruit?
- Coconut
- Mango
- Pea
- Banana
Answer
D. Banana
Banana develops without fertilisation and is seedless.
The edible part of a mango fruit is the
- endocarp
- mesocarp
- testa
- epicarp
Answer
B. mesocarp
In mango, a drupe, the mesocarp is fleshy and edible; the endocarp is stony.
In a maize grain, the sheath that encloses the radicle is the
- coleoptile
- aleurone layer
- coleorhiza
- scutellum
Answer
C. coleorhiza
The radicle is enclosed by the coleorhiza and the plumule by the coleoptile.
The stamens of a pea flower are
- diadelphous
- epiphyllous
- monadelphous
- polyadelphous
Answer
A. diadelphous
The pea androecium is (9) + 1, in two bundles, so it is diadelphous.
Given below are two statements: Statement I: Fibrous roots are typical of monocots. Statement II: In the fibrous root system the primary root is long-lived. Choose the correct option.
- Both Statement I and Statement II are correct
- Both Statement I and Statement II are incorrect
- Statement I is correct but Statement II is incorrect
- Statement I is incorrect but Statement II is correct
Answer
C. Statement I is correct but Statement II is incorrect
Fibrous roots occur in monocots, but the primary root is short-lived and replaced by many roots.
Given below are two statements: Statement I: Pneumatophores are present in banyan. Statement II: Stilt roots of maize arise from the lower nodes of the stem. Choose the correct option.
- Both Statement I and Statement II are correct
- Both Statement I and Statement II are incorrect
- Statement I is correct but Statement II is incorrect
- Statement I is incorrect but Statement II is correct
Answer
D. Statement I is incorrect but Statement II is correct
Pneumatophores are found in mangrove plants such as Rhizophora, so I is incorrect; stilt roots of maize arise from lower nodes, so II is correct.
Given below are two statements: Statement I: In a cymose inflorescence the main axis terminates in a flower. Statement II: In a racemose inflorescence the flowers are borne in acropetal succession. Choose the correct option.
- Both Statement I and Statement II are correct
- Both Statement I and Statement II are incorrect
- Statement I is correct but Statement II is incorrect
- Statement I is incorrect but Statement II is correct
Answer
A. Both Statement I and Statement II are correct
Both statements are correct: cymose is limited in growth; racemose is acropetal.
Given below are two statements: Statement I: Hypogynous flowers have an inferior ovary. Statement II: The rose flower is epigynous. Choose the correct option.
- Both Statement I and Statement II are correct
- Both Statement I and Statement II are incorrect
- Statement I is correct but Statement II is incorrect
- Statement I is incorrect but Statement II is correct
Answer
B. Both Statement I and Statement II are incorrect
Hypogynous flowers have a superior ovary, and rose is perigynous, so both are incorrect.
Which of the following statements are correct? 1. Sweet potato is a modified root. 2. Potato is a modified stem. 3. Turmeric is a modified root.
- 1 and 2 only
- 2 and 3 only
- 1 and 3 only
- 1, 2 and 3
Answer
A. 1 and 2 only
Sweet potato is a root; potato is a stem; turmeric is a rhizome (stem).
Given below are two statements: Statement I: The thorns of Citrus are modified leaves. Statement II: The tendrils of watermelon arise from axillary buds. Choose the correct option.
- Both Statement I and Statement II are correct
- Both Statement I and Statement II are incorrect
- Statement I is correct but Statement II is incorrect
- Statement I is incorrect but Statement II is correct
Answer
D. Statement I is incorrect but Statement II is correct
Citrus thorns are modified axillary buds, so Statement I is incorrect; watermelon tendrils are stem modifications from axillary buds.
Given below are two statements: Statement I: Fabaceae has a monocarpellary ovary with a superior position. Statement II: The ovary of Fabaceae is bicarpellary and bilocular. Choose the correct option.
- Both Statement I and Statement II are correct
- Both Statement I and Statement II are incorrect
- Statement I is correct but Statement II is incorrect
- Statement I is incorrect but Statement II is correct
Answer
C. Statement I is correct but Statement II is incorrect
Fabaceae has a monocarpellary, unilocular ovary; the fruit is a legume.
Given below are two statements: Statement I: Liliaceae has a tricarpellary, syncarpous ovary. Statement II: The perianth of Liliaceae has six tepals in two whorls of three. Choose the correct option.
- Both Statement I and Statement II are correct
- Both Statement I and Statement II are incorrect
- Statement I is correct but Statement II is incorrect
- Statement I is incorrect but Statement II is correct
Answer
A. Both Statement I and Statement II are correct
Both are correct: gynoecium is G(3) and the perianth is P(3+3).
Which of the following statements are correct? 1. Potato belongs to Solanaceae. 2. Colchicine is obtained from Colchicum autumnale of Liliaceae. 3. Soyabean belongs to Solanaceae.
- 1 and 2 only
- 2 and 3 only
- 1 and 3 only
- 1, 2 and 3
Answer
A. 1 and 2 only
Potato is Solanaceae and Colchicum is Liliaceae; soyabean is Fabaceae.
Given below are two statements: Statement I: The aleurone layer separates the endosperm from the embryo in a maize grain. Statement II: A castor seed is non-endospermic. Choose the correct option.
- Both Statement I and Statement II are correct
- Both Statement I and Statement II are incorrect
- Statement I is correct but Statement II is incorrect
- Statement I is incorrect but Statement II is correct
Answer
C. Statement I is correct but Statement II is incorrect
Aleurone layer lies between them; castor is an endospermic dicot seed.
Assertion (A): Pneumatophores are present in mangrove plants. Reason (R): They take in air for respiration in waterlogged, saline soil.
- Both A and R are true and R is the correct explanation of A
- Both A and R are true but R is not the correct explanation of A
- A is true but R is false
- A is false but R is true
Answer
A. Both A and R are true and R is the correct explanation of A
Pneumatophores grow upward out of the mud and supply oxygen to the roots.
Assertion (A): Banyan has stilt roots. Reason (R): Banyan has prop roots that hang from its branches.
- Both A and R are true and R is the correct explanation of A
- Both A and R are true but R is not the correct explanation of A
- A is true but R is false
- A is false but R is true
Answer
D. A is false but R is true
Banyan has prop roots, not stilt roots, so A is false; R is true.
Assertion (A): A potato tuber is a stem modification. Reason (R): A potato tuber stores food.
- Both A and R are true and R is the correct explanation of A
- Both A and R are true but R is not the correct explanation of A
- A is true but R is false
- A is false but R is true
Answer
B. Both A and R are true but R is not the correct explanation of A
Both true, but food storage does not show that it is a stem; the eyes (nodes with buds) do.
Assertion (A): Mustard shows axile placentation. Reason (R): In axile placentation the ovules are borne on the central axis of a multilocular ovary.
- Both A and R are true and R is the correct explanation of A
- Both A and R are true but R is not the correct explanation of A
- A is true but R is false
- A is false but R is true
Answer
D. A is false but R is true
Mustard has parietal placentation, so A is false; R is a correct definition.
Assertion (A): The pea flower is zygomorphic. Reason (R): It has a papilionaceous corolla made of a standard, two wings and two keel petals.
- Both A and R are true and R is the correct explanation of A
- Both A and R are true but R is not the correct explanation of A
- A is true but R is false
- A is false but R is true
Answer
A. Both A and R are true and R is the correct explanation of A
The unequal petals give bilateral symmetry, which explains the zygomorphy.
Assertion (A): Opuntia has a green, fleshy flattened stem. Reason (R): The leaves of Opuntia are modified into tendrils.
- Both A and R are true and R is the correct explanation of A
- Both A and R are true but R is not the correct explanation of A
- A is true but R is false
- A is false but R is true
Answer
C. A is true but R is false
A is true (phylloclade); its leaves are reduced to spines, not tendrils, so R is false.
Match List I with List II. List I: a. Prop root b. Stilt root c. Pneumatophore d. Storage root List II: i. Rhizophora ii. Carrot iii. Maize iv. Banyan
- a-i, b-iii, c-iv, d-ii
- a-iv, b-iii, c-i, d-ii
- a-iii, b-iv, c-i, d-ii
- a-iv, b-iii, c-ii, d-i
Answer
B. a-iv, b-iii, c-i, d-ii
Prop root: banyan; stilt: maize; pneumatophore: Rhizophora; storage: carrot.
Match List I with List II. List I: a. Valvate b. Twisted c. Imbricate d. Vexillary List II: i. Cassia ii. Pea iii. Calotropis iv. China rose
- a-i, b-iv, c-iii, d-ii
- a-iii, b-iv, c-i, d-ii
- a-iv, b-iii, c-i, d-ii
- a-iii, b-iv, c-ii, d-i
Answer
B. a-iii, b-iv, c-i, d-ii
Valvate: Calotropis; twisted: China rose; imbricate: Cassia; vexillary: pea.
Match List I with List II. List I: a. Marginal b. Axile c. Parietal d. Basal List II: i. Sunflower ii. Mustard iii. Pea iv. Tomato
- a-iv, b-iii, c-ii, d-i
- a-iii, b-iv, c-ii, d-i
- a-iii, b-iv, c-i, d-ii
- a-ii, b-iv, c-iii, d-i
Answer
B. a-iii, b-iv, c-ii, d-i
Marginal: pea; axile: tomato; parietal: mustard; basal: sunflower.
Match List I with List II. List I: a. Runner b. Stolon c. Offset d. Sucker List II: i. Mint ii. Banana iii. Grass iv. Water hyacinth
- a-i, b-iii, c-iv, d-ii
- a-iv, b-i, c-iii, d-ii
- a-iii, b-i, c-ii, d-iv
- a-iii, b-i, c-iv, d-ii
Answer
D. a-iii, b-i, c-iv, d-ii
Runner: grass; stolon: mint; offset: water hyacinth (Eichhornia); sucker: banana.
Match List I with List II. List I: a. Scutellum b. Coleoptile c. Coleorhiza d. Aleurone layer List II: i. Sheath of radicle ii. Single cotyledon iii. Layer between endosperm and embryo iv. Sheath of plumule
- a-i, b-iv, c-ii, d-iii
- a-ii, b-iv, c-iii, d-i
- a-ii, b-iv, c-i, d-iii
- a-iv, b-ii, c-i, d-iii
Answer
C. a-ii, b-iv, c-i, d-iii
Scutellum is the single cotyledon; coleoptile covers plumule; coleorhiza covers radicle; aleurone lies between endosperm and embryo.
Match List I with List II. List I: a. Actinomorphic b. Zygomorphic c. Calyx d. Superior ovary List II: i. Bilateral symmetry ii. Radial symmetry iii. Line below G iv. Outermost whorl
- a-i, b-ii, c-iv, d-iii
- a-ii, b-i, c-iii, d-iv
- a-ii, b-iii, c-iv, d-i
- a-ii, b-i, c-iv, d-iii
Answer
D. a-ii, b-i, c-iv, d-iii
Actinomorphic: radial; zygomorphic: bilateral; calyx: outermost whorl; superior ovary: line below G.
A plant has simple alternate leaves, a bisexual actinomorphic flower with five united sepals, five united petals, five epipetalous stamens, a bilocular superior ovary and a berry fruit. It belongs to
- Liliaceae
- Poaceae
- Solanaceae
- Fabaceae
Answer
C. Solanaceae
These features, and the formula K(5) C(5) A5 G(2), identify Solanaceae.
A flower has six tepals in two whorls of three, six stamens attached to the tepals, and a superior tricarpellary syncarpous ovary with axile placentation. The family is
- Fabaceae
- Liliaceae
- Solanaceae
- Brassicaceae
Answer
B. Liliaceae
P(3+3) A3+3 G(3) is the formula of Liliaceae.
A gardener wants to multiply mint plants quickly from a lateral branch that bends down and roots at the nodes. The branch is a
- thorn
- tendril
- phylloclade
- stolon
Answer
D. stolon
A stolon is a lateral branch from the base of the main stem that touches the ground and roots; mint propagates this way.
A seed is split in two. It shows a hilum and micropyle, two cotyledons and no endosperm. It is most likely
- castor
- bean
- wheat
- maize
Answer
B. bean
Bean is a non-endospermic dicot seed; maize and wheat are monocots; castor is endospermic.
In a guava flower the ovary lies below the sepals, petals and stamens. This condition is called
- epigynous
- hypogynous
- apocarpous
- perigynous
Answer
A. epigynous
In an epigynous flower the ovary is inferior, with the other parts above it.
In a swampy mangrove area, roots of a plant grow upward out of the mud. Their main function is
- gaseous exchange
- anchorage only
- storage of food
- vegetative propagation
Answer
A. gaseous exchange
These pneumatophores take in air for respiration in oxygen-poor soil.
In the floral formula K(5) C1+2+(2) A(9)+1 G1, the stamens are
- five fused and five free
- nine free and one fused
- nine fused and one free
- ten fused
Answer
C. nine fused and one free
A(9)+1 means nine stamens fused in one bundle and one stamen free, as in pea (diadelphous).