Plant Cells and Tissue Systems

Basic structural and functional units of plants
Cell wall: rigid outer layer, composed of cellulose, hemicellulose, and pectin
Plasma membrane: semi-permeable membrane, regulates movement of substances in and out of the cell
Cytoplasm: jelly-like substance inside the cell, contains organelles and metabolites
Nucleus: control center of the cell, contains genetic material (DNA)

Dermal tissue: outer layer, protects the plant from external factors (e.g., epidermis, cuticle)
Ground tissue: filler tissue, provides support and storage (e.g., parenchyma, collenchyma, sclerenchyma)
Vascular tissue: responsible for transportation of water, nutrients, and sugars (e.g., xylem, phloem)

Root cap: protective layer at the tip of the root, helps to push through soil
Root hair: increases surface area for absorption of water and nutrients
Cortex: layer of cells just beneath the epidermis, stores food and water
Vascular cylinder: central region of the root, contains xylem and phloem

Epidermis: outer layer, protects the stem from external factors
Cortex: layer of cells just beneath the epidermis, stores food and water
Vascular bundle: group of xylem and phloem tissues, responsible for transportation
Pith: central region of the stem, stores food and provides support

Cuticle: waxy layer on the surface of the leaf, prevents water loss
Epidermis: outer layer, protects the leaf from external factors
Mesophyll: inner tissue, responsible for photosynthesis (e.g., palisade parenchyma, spongy parenchyma)
Vascular bundle: group of xylem and phloem tissues, responsible for transportation

Xylem: responsible for transporting water and minerals from roots to leaves
- Tracheids: dead cells that provide structural support and transport water
- Vessel elements: dead cells that transport water and minerals
Phloem: responsible for transporting sugars and other organic compounds from leaves to roots
- Sieve cells: living cells that transport sugars and other organic compounds
- ** Companion cells**: living cells that provide energy and support to sieve cells

Plant cells have a rigid outer layer called the cell wall, composed of cellulose, hemicellulose, and pectin.
The semi-permeable plasma membrane regulates the movement of substances in and out of the cell.
Cytoplasm is a jelly-like substance inside the cell that contains organelles and metabolites.
The nucleus is the control center of the cell, containing genetic material (DNA).

Dermal tissue is the outer layer of the plant, protecting it from external factors.
Ground tissue provides support and storage, and includes parenchyma, collenchyma, and sclerenchyma cells.
Vascular tissue is responsible for transporting water, nutrients, and sugars throughout the plant.

The root cap is a protective layer at the tip of the root, helping to push through soil.
Root hair increases the surface area for absorption of water and nutrients.
The cortex is a layer of cells just beneath the epidermis, storing food and water.
The vascular cylinder is the central region of the root, containing xylem and phloem.

The epidermis is the outer layer of the stem, protecting it from external factors.
The cortex is a layer of cells just beneath the epidermis, storing food and water.
Vascular bundles are groups of xylem and phloem tissues, responsible for transportation.
The pith is the central region of the stem, storing food and providing support.

The cuticle is a waxy layer on the surface of the leaf, preventing water loss.
The epidermis is the outer layer of the leaf, protecting it from external factors.
Mesophyll is the inner tissue of the leaf, responsible for photosynthesis.
Vascular bundles are groups of xylem and phloem tissues, responsible for transportation.

Xylem is responsible for transporting water and minerals from roots to leaves.
Tracheids are dead cells that provide structural support and transport water.
Vessel elements are dead cells that transport water and minerals.
Phloem is responsible for transporting sugars and other organic compounds from leaves to roots.
Sieve cells are living cells that transport sugars and other organic compounds.
Companion cells are living cells that provide energy and support to sieve cells.