The process where certain species of soil convert atmospheric nitrogen to ammonia
Plants that have their own nitrogen-fixing bacteria
Lumps on a legume's roots where the nitrogen-fixing bacteria are
Protein and nucleic acid synthesis
cell wall formation; enzyme activity
tiny outgrowths of the root's epidermal cells. They increase the surface area available for absorbing water and dissolved minerals
helps push water up the xylem and usually operates at night
A layer of cells that surround the vascular tissue and have waxy cell walls. The wax prevents water and minerals from leaking back out of the xylem.
The loss of water through leaves due to evaporation. It creates a pull force that pulls the xylem sap up a tree because of cohesion and adhesion.
long cells with tapered ends
wider, shorter, less tapered cells.
Are located around each stoma, they open and close the stoma by changing shape.
Chain of cells that phloem sap goes through.
Located alongside the sieve tubes, and provide proteins and other resources to the sieve-tube members.
Process by which poem sap moves through a plant
Source to Sink
Sugar starts at source, then moves to "sink"
A type of plant that grows on the surface of other plants and absorbs its water and minerals from rain water that falls on their leaves. They still photosynthesize.
Plants that obtain some/all of their nutrients from host plants
Charles Darwin and Francis
These two men did experiments that showed plant stems bend in response to light at the tip of the shoots.
Chemical messengers produced in the shoot tip.
Promotes plant growth
Produced in apical meristem
Promote cell elongation
Builds up on the shaded side and stimulates growth beneath the meristem
The uneven growth causes the plant to bend
Stimulate cell division
Produced in actively dividing tissues like embryos, roots and fruits
Slows the aging of flowers and fruits
Produced at the tips of both stems and roots
Cause a wide variety of effects
Promotes cell division and elongation (like auxin's)
With auxins- can influence fruit development
Promotes seed germination in some species
Inhibits cell devision (halts primary and secondary growth)
Occurs during plant dormancy
Acts as a "stress hormone" (causes stomata to close in a dehydrated plant)
Also known as ABA
Stimulates fruit ripening
Promotes leaf drop
Only found in gas form
Growth responses that cause parts of a plant to grow slowly toward or away from a stimulus
-Regulated by plant hormones, especially auxins
-Not rapidly reversible
Response to touch
Response to light
Response to gravity
salt-tolerant plants with adaptations such as salt glands
A biological cycle that occurs every 24 hours
The ability to use the environment stimulus of darkness to time time seasonal activities
Critical Night Length
How long it must be dark outside in order for short-day plants to bloom
Flower in winter
Require LONG periods of darkness
EX: Chrysanthemums and poinsettias
Flower in the late spring/early summer
Require SHORT periods of darkness
EX: Spinach, Lettuces and Irises
Day Neutral Plants
Flower when the plant reaches a certain stage of maturity
They do no require certain day/night lengths
EX: Dandelions, Tomatoes, and Rice
Pigmented proteins that plants use to detect sunrise and sunset. When they absorb the red-light that is abundant at sunrise, they change snap to an active form that triggers a variety of plant responses