[ 2MID ] General Biology - Modification

Spines

In most xerophytes (plants that grow in regions with scarce water), the leaves are reduced to these but still take the responsibility of doing photosynthesis. These help reduce water loss and is also useful in absorbing droplets of water from the fog.

Succulent Leaves

These fleshy leaves that that serve as a storage part for water as well as reserve materials. The plants can survive for months without even a single drop of water and may turn brown.

Tendrils

found in climbers where leaf of plants are modified into elongated structures to help the plants climb efficiently.

Swollen Petiole

aquatic plants that have bulged petioles filled with air and help the plant float in water.

Reproductive Leaves

adventitious buds along their leaf margins. These buds develop roots while on the parent plant as they mature, they fall off the plant and start growing into a new plant when they land on nearby soil.

Sheathy Leaf Bases

found in plants that lack woody stems. The leaf base is expanded into a sheath that is rolled over one another in layers as new leaves grow. The sheathy leaf bases combine to form the pseudostem that’s supports the plant to stand erect.

Traps

plants that grow in nitrogen deficient places have modified their leaves to get this. The leaves may be modified into a pod which is used to attract insects and other tiny animals to fall inside and digest them. The inner walls secrete digestive enzymes that help digest the insects and extract the nitrogen needed for the plant.

Bulbs

leaves modified as storage organ.

Bud Scales

tough, overlapping, waterproof leaves that protect buds from frost, desiccation, and pathogens. These form before the onset of unfavorable growing seasons i.e. winter.

Bract

a modified leaf or scale, typically small, with a flower or flower cluster in its axil. These are sometimes larger and more brightly coloured than the true flower.

Rhizome

also called creeping rootstalk, horizontal underground plant stems capable of producing the shoot and root systems of a new plant

Corm

a condensed form of the stem that grows in the vertical direction. It is spherical in shape with a flattened base. It has distinct nodes and internodes. Adventitious roots are present either at the base or all over the body.

Tubers

enlarged structures in some plant species used as storage organs for nutrients

Runner/Stolon

It is a creeper that runs horizontally on the surface of the soil. These break off and grow into an independent plant giving rise to vegetative propagation.

Sucker

This arises from the basal part of the main stem. Before separating from the original plant, it develops adventitious roots and leafy shoots. It moves horizontally under the soil for a distance and then grows obliquely upwards

Offset

a modification of stem in which a lateral branch with short internode and each node bearing a rosette of leaves and a tuft of roots. This type of modification is found in aquatic plants.

Thorns

These are straight, pointed, hard or woody structures sometimes they bear leaves, flowers or even may be branched.

Roots

Anchor a vascular plant to the soil, absorb minerals and water, and often store carbohydrates

Root System

the subterranean or underground part of the plant body

Shoot

the aboveground part of the plant body

Geotropism

a coordinated process of differential growth by a plant in response to gravity pulling on it.

Buttress

are aerial extensions of lateral surface roots and form only in certain species. These roots stabilize the tree, especially in shallow saturated soils, thereby resisting toppling.

Prop Roots

Any of the modified roots that arise from the stem of certain plants and provide extra support.

Pneumatophores

An aerial root specialized for gaseous exchange.

Aerial/Strangling Root

extend to the ground, supporting the growing plant, which eventually strangles the host tree.

Storage Roots

the taproot becomes enlarged and swollen due to the storage of food.

Calyx

This is the outermost whorl of the flower which consists of sepals.

Sepals

This is usually green and they enclose and protect the developing bud

Corolla

The whorl next to calyx which consists of petals, which usually help to attract the pollinators.

Androecium

The whorl next to the corolla which consists of male organs called stamens.

Stamen

This consists of a slender stalk or filament attached to the flower at its base and carrying on its free, upper end, a structure called an anther, which contains the pollen.

Gynoecium

The innermost whorl of the flower which consists of the female organs called carpels.

Carpel

This consists of a basal ovary containing the ovules, a slender column-shaped structure, the style, and on the end of the style the stigma, the function of which is to receive the pollen grains.

Style

Part of a flower that is a slender column-shaped structure

Stigma

Part of the flower and the function of which is to receive the pollen grains.

Fruit

the fleshy or dry ripened ovary of a flowering plant, enclosing the seed or seeds.

Exocarp

refers to the outermost layer of the pericarp—which is variously called the skin, rind, peel, or husk of a fruit—that covers the mesocarp

Mesocarp

refers to the middle layer of a fruit, the usually fleshy plump part.

Endocarp

is the name for the inner region of the pericarp and can consist of layers of different textures or consistency that surround and protect the seed

Drupe

a type of fleshy fruit containing a large seed, for example, peaches, cherries, and apricots. Botanically, other types of drupe that could also be a classified under this category are some berries.

Berries

a fleshy fruit formed from the ovary of one flower with a seed or seeds embedded in the flesh.

Pomes

fruits in this category have a fleshy area surrounding a core containing seeds.

Hesperidia

fruits have a thick tangy rind and sectioned pulp inside

Pepo

fruits have multiple seeds throughout the flesh or grouped together in the center.

Rhizome

Corm

Tubers

Runner/Stolon

Sucker

Offset

Thorns

Buttress

Prop Roots

Pneumatophores

Aerial/Strangling Roots

Storage Roots

Dicotyledons

They show the following distinguishing characteristics:

 We see taproots in the members of this group.
 The leaves in members of these class exhibit reticulate (net-like) venation.

 The flowers are tetramerous or pentamerous having four or five members in the various floral whorls, respectively.

 The vascular bundles arranged in a ring, number 2–6, open and with cambium.

 The seeds of dicotyledons are with two cotyledons as the name indicate.

Monocotyledons

They show following distinguishing characteristics:

 We see adventitious roots in the members of this group.

 The leaves are simple with parallel venation.

 The flowers are trimerous. They have three members in each floral whorl.

 The vascular bundles scattered in the ground tissue, many in number, closed and without cambium.

 The seeds of monocotyledons are with one cotyledon as the name indicates. e.g., Cereals, bamboos, sugarcane, palms, banana, lilies and orchids.

Taproot System

consists of a primary root that grows deep into the soil, with smaller lateral roots branching off. It provides strong anchorage and is common in dicot plants like carrots and dandelions.

Fibrous Root System

consists of many thin, branching roots that spread out near the surface. It provides good soil grip and is common in monocot plants like grass and wheat.