Reproduction in Organisms

Flashcards about Reproduction in Organisms lecture notes.

Reproduction

Production of young ones like parents.

Asexual reproduction

Does not involve gamete fusion, single parent

Sexual reproduction

Involves fusion of gametes, biparental.

Vegetative Propagation

Reproduction takes place with the help of vegetative parts like root or leaf.

Cutting

Small piece of any vegetative part of a plant having one or more buds is used for propagation.

Grafting

Parts of two plants are joined in such a way that they grow as one plant.

Tissue Culture

A small amount of plant tissue is grown to give rise to multiple plants.

Propagule

Part of the stem containing more than one bud.

Stock

The rooted plant to which the scion is joined

Microsporangia

Pollen sacs in anthers, therefore, it is called tetra sporenges.

Epidermis

Outer most protecting layer of anther wall.

Endothecium

Sub-epidermal layer of anther wall.

Middle Layer

Layer of thin walled cells in anther wall, 1-2 layers.

Tapetum

Innermost, nutrient layer of anther wall.

Microsporogenesis

Formation of pollen grains through meiosis with the help of microspore mother cell.

Exine

The outer layer of the pollen grain.

Intine

The inner layer of the pollen grain

Apocarpous

Union of ovary.

Syncarpous

Multi ovulate

Funicule

Each ovule is attached to the placenta by a small stalk.

Hilum

The place of attachment of the funiculus with the main body.

Nucellus

The ovule consists of central paranchyma tissue.

Outer Integument

The outer covering of nucellus.

Inner Integument

The inner covering of nucellus.

Microphyle

The narrow opening at the apex of the ovule.

Megasporogenesis

Formation of a haploid megaspore from a diploid mother cell

Pollination

Transfer of pollen grains from anther to a stigma.

Self Pollination

Pollen from the same flower lands on the stigma.

Cross Pollination

Pollen from a different flower lands on the stigma.

Outbreeding Devices

A mechanism that prevents self-pollination and favors cross-pollination.

Dichogamy

Male and female organs mature at different times.

Herkogamy

Pollen grain of another flower matures faster.

Double Fertilization

Fertilisation takes place 2 times.

The significance of seeds

Seeds are important propagating organs.

Significance of fruits

Fruits provide nutrition and protection of seeds.

Dormancy

A period of growth arrest in seeds.

Apomixis

Formation of embryo through asexual methods (without gamete formation and fertilization).

Non-recurrent Apomixis

Embryo from egg without fertilisation.

Parthenocarpy

Fruit develops without fertilisation.

Polyembryony

Development of more than one embryo