Morphology Of Flowering Plants

What is morphology?

The study of external form and structure of plants

What are the main vegetative parts of a flowering plant?

Root stem and leaf

What are the main reproductive parts of a flowering plant?

Flower fruit and seed

What is the root system?

The underground part of a plant that usually develops from the radicle

What are the main functions of roots?

Anchorage absorption of water and minerals conduction and storage of food

What is the primary root?

The root that develops directly from the radicle

What is tap root system?

A root system with one main primary root and smaller lateral roots

Which plants generally have a tap root system?

Dicotyledonous plants

What is a fibrous root system?

A root system consisting of many thin roots arising from the base of the stem

Which plants generally have fibrous roots?

Monocotyledonous plants

What are adventitious roots?

Roots that arise from parts of the plant other than the radicle

What are root hairs?

Thin unicellular extensions of epidermal cells that increase the surface area for absorption

What is the root cap?

A protective structure covering the root tip

What is the region of meristematic activity?

The region near the root tip containing actively dividing cells

What is the region of elongation?

The region behind the meristematic region where cells elongate

What is the region of maturation?

The region where cells differentiate and root hairs develop

What is a root modification?

A structural change in roots that allows them to perform special functions

What are storage roots?

Modified roots that store food

Give examples of storage roots

Carrot radish turnip and sweet potato

What are prop roots?

Roots arising from branches that grow vertically downward and provide mechanical support

Give an example of prop roots

Banyan

What are stilt roots?

Roots arising from lower nodes of the stem that grow obliquely into the soil and provide support

Give examples of stilt roots

Maize and sugarcane

What are pneumatophores?

Roots that grow vertically upward in swampy areas and help in gaseous exchange

Give an example of pneumatophores

Rhizophora

What is the stem?

The ascending part of the plant axis that develops from the plumule

What are the main functions of the stem?

Support conduction and bearing leaves flowers and fruits

What is a node?

The point on the stem where leaves or branches arise

What is an internode?

The portion of the stem between two successive nodes

What is a terminal bud?

A bud present at the tip of a stem or branch

What is an axillary bud?

A bud present in the axil of a leaf

What is a stem modification?

A structural change in the stem that allows it to perform special functions

What are underground stem modifications?

Modified stems that occur below the soil surface and help in storage perennation and vegetative propagation

What is a rhizome?

A horizontal underground stem with nodes internodes scale leaves and buds

Give an example of a rhizome

Ginger

What is a tuber?

A swollen underground stem that stores food and has buds called eyes

Give an example of a tuber

Potato

What is a bulb?

A short underground stem surrounded by fleshy scale leaves

Give examples of bulbs

Onion and garlic

What is a corm?

A short vertical underground stem that stores food

Give examples of corms

Colocasia and Gladiolus

What are subaerial stem modifications?

Modified stems that grow partly above and partly below the ground and help in vegetative propagation

What is a runner?

A slender stem that grows horizontally above the ground and develops roots at nodes

Give an example of a runner

Grass

What is a stolon?

A lateral branch that grows above the ground and bends down to touch the soil where it develops roots

Give an example of a stolon

Strawberry

What is a sucker?

A lateral branch arising from the underground portion of the stem that grows obliquely upward

Give an example of a sucker

Chrysanthemum

What is a leaf?

A lateral generally flattened structure borne at a node of the stem

What is the main function of a leaf?

Photosynthesis

What are the three main parts of a typical leaf?

Leaf base petiole and lamina

What is the leaf base?

The part of the leaf attached to the stem

What is the petiole?

The stalk that connects the leaf base to the lamina

What is the lamina?

The broad green part of the leaf

What is venation?

The arrangement of veins and veinlets in the lamina

What is reticulate venation?

Veins and veinlets form a network

Which plants generally have reticulate venation?

Dicotyledons

What is parallel venation?

Veins run parallel to one another

Which plants generally have parallel venation?

Monocotyledons

What is phyllotaxy?

The pattern in which leaves are arranged on the stem

What are the three main types of phyllotaxy?

Alternate opposite and whorled

What is alternate phyllotaxy?

One leaf arises at each node in an alternate arrangement

Give examples of alternate phyllotaxy

China rose mustard and sunflower

What is opposite phyllotaxy?

Two leaves arise at each node opposite each other

Give examples of opposite phyllotaxy

Calotropis and guava

What is whorled phyllotaxy?

More than two leaves arise at each node forming a whorl

Give an example of whorled phyllotaxy

Alstonia

What is a simple leaf?

A leaf whose lamina is entire or incised but the incisions do not reach the midrib

What is a compound leaf?

A leaf whose lamina is divided into distinct leaflets

What is a pinnately compound leaf?

A compound leaf in which leaflets are arranged along a common axis called rachis

Give examples of pinnately compound leaves

Neem and rose

What is a palmately compound leaf?

A compound leaf in which leaflets arise from a common point

Give examples of palmately compound leaves

Silk cotton and lupin

What is leaf modification?

A structural change in a leaf that allows it to perform a specialised function

What are tendrils?

Thread-like leaf modifications that help plants climb

Give examples of leaf tendrils

Pea and some members of Fabaceae

What are spines?

Modified leaves that protect plants from herbivores and reduce water loss

Give an example of leaf spines

Cactus

What is a pitcher leaf?

A leaf modified into a pitcher that helps trap insects

Give an example of pitcher leaves

Nepenthes

What is an inflorescence?

The arrangement of flowers on the floral axis

What is racemose inflorescence?

An inflorescence in which the main axis continues to grow and flowers are arranged acropetally

What does acropetal succession mean?

Older flowers are towards the base and younger flowers are towards the apex

What is cymose inflorescence?

An inflorescence in which the main axis terminates in a flower and growth is limited

What does basipetal succession mean?

Older flowers are towards the apex and younger flowers are towards the base

What is a flower?

A modified shoot in which the shoot apical meristem changes into a floral meristem

What are the four whorls of a typical flower?

Calyx corolla androecium and gynoecium

What are accessory whorls?

Calyx and corolla

What are essential reproductive whorls?

Androecium and gynoecium

What is the calyx?

The outermost whorl of a flower consisting of sepals

What is the corolla?

The whorl consisting of petals

What is the androecium?

The male reproductive whorl consisting of stamens

What is the gynoecium?

The female reproductive whorl consisting of carpels

What is a sepal?

A member of the calyx

What is a petal?

A member of the corolla

What is a stamen?

The male reproductive structure of a flower

What are the two main parts of a stamen?

Filament and anther

What is the filament?

The stalk of a stamen

What is the anther?

The terminal bilobed structure of a stamen that produces pollen grains

What is a typical anther?

A bilobed dithecous structure with four pollen sacs