Easy Bio Notes

Active Transport

Process that requires energy to move substances against a concentration gradient (low to high).

Passive Transport

Movement of substances across a cell membrane without the use of energy, moving from high to low concentration.

Osmosis

The diffusion of water across a selectively permeable membrane from an area of low solute concentration to an area of high solute concentration.

Diffusion

The movement of molecules from an area of high concentration to an area of low concentration.

Hypertonic

A solution with a higher concentration of solute outside the cell, causing the cell to shrink.

Hypotonic

A solution with a lower concentration of solute outside the cell, causing the cell to swell.

Isotonic

A solution where the concentration of solute is the same inside and outside the cell, keeping the cell size constant.

Photosynthesis

The process by which plants use sunlight, carbon dioxide, and water to produce sugar and oxygen.

Dermal Tissue

The outer layer of a plant that provides protection.

Ground Tissue

Tissue found inside a plant that provides support, storage, and photosynthesis.

Vascular Tissue

Tissue in plants that transports water (xylem) and food (phloem).

Cuticle

A waxy layer on leaves that prevents water loss.

Upper Epidermis

The top protective layer of cells on a leaf.

Palisade Mesophyll

The upper layer of leaf cells where most photosynthesis occurs.

Vein

The structure in a plant that contains both xylem and phloem for transport.

Lower Epidermis

The bottom protective layer of cells on a leaf that contains stomata.

Spongy Mesophyll

Layer of cells in a leaf that contains air spaces for gas exchange.

Guard Cells

Specialized cells that control the opening and closing of stomata.

Stomata

Pores in the leaf that allow for the exchange of gases (CO₂ in, O₂ out).

Transpiration

The process of water loss from leaves through stomata.

Transport (H₂O/Glucose)

Xylem carries water upward, while phloem carries sugar downward in a plant.

Phototropism

The growth of a plant toward light.

Gravitropism

The growth of a plant in response to gravity, either toward or away from it.

Hydrotropism

The growth of a plant toward water.

Auxins

Plant hormones that regulate growth and response to stimuli.

Root System

The part of a plant located underground that absorbs water and nutrients.

Shoot System

The part of a plant above ground that includes stems, leaves, and flowers, supporting the plant and making food.

Open System

A system that exchanges materials with the environment, such as water, air, and nutrients.

Surface Area

The total area of the surface of a three-dimensional object, important for processes like absorption and gas exchange.