Plant systems

nitrogen-fixing bacteria

bacteria that convert nitrogen in the air into forms that can be used by plants and animals

xylem

Nonliving vascular tissue that carries water and dissolved minerals from the roots of a plant to its leaves

phloem

Living vascular tissue that carries sugar and organic substances throughout a plant

Stimulus

A change in an organism's surroundings that causes the organism to react

Transpiration

loss of water from a plant through its leaves

vegetative propagation

form of asexual reproduction occurring in plants in which a new plant grows from a fragment of the parent plant

root hairs

tiny hair-like extensions that increase the surface area of the root allowing it to absorbs more water and nurtients

root system

All of a plant's roots that anchor it in the soil, absorb and transport minerals and water, and store food.

shoot system

consists of stems and leaves

ovule

the part of the ovary of seed plants that contains the female gamete and after fertilization becomes the seed.

pollination

The transfer of pollen from male reproductive structures to female reproductive structures in plants

pistil

The female reproductive part of a flower

stamen

The male reproductive part of a flower

auxin

a plant hormone which causes the elongation of cells in shoots and is involved in regulating plant growth.

stomata

A tiny pore in a plant leaf surrounded by a pair of guard cells that regulate its opening and closure, and serves as the site for gas exchange.

phototropism

A plant's response to light

thigmotropism

A directional growth of a plant in response to touch.

gravitropism/geotropism

response of a plant to the force of gravity (positive gravitropism = with gravity, negative gravitropism = against gravity)

hydrotropism

a plants growth response to water; plant grows towards the water