NATURE AND COMPOSITION OF PLANTS

Cell

The smallest structure in the universe capable of growth and reproduction; the basic unit of every living organism.

Plant Cell

Contains chloroplasts for photosynthesis, a rigid cell wall, and a large central vacuole.

Animal Cell

Contains centrioles and lysosomes, involved in cell division and digestion, respectively.

Cell Wall

Provides mechanical protection and rigidity to the plant cell, composed mainly of cellulose.

Cytoplasm

Gel-like material that suspends organelles and distributes substances within the cell.

Plasmalemma/Plasma Membrane

Selectively permeable membrane that regulates substance movement in and out of the cell.

Endoplasmic Reticulum

Network of flattened disks or tubular sacs involved in lipid and protein synthesis.

Golgi Apparatus

Involved in the synthesis of polysaccharides and secretion of proteins and carbohydrates.

Mitochondria

Organelles responsible for respiration and energy production in the cell.

Plastids

Organelles involved in photosynthesis and storage, including chloroplasts, chromoplasts, and leucoplasts.

Microbodies

Organelles involved in metabolic processes, including peroxisomes and lyoxysomes.

Cytoskeleton

A network of fibrous proteins that provides structure and support to the cell.

Ribosomes

Small particles involved in protein synthesis.

Vacuoles

Membrane-bound structures that store substances and help maintain cell turgor.

Nucleus

Contains genetic information and controls cell activities.

Meristematic Tissue

Tissue where cell division occurs, responsible for plant growth.

Permanent Tissue

Mature tissue that performs specific functions in plants.

Xylem

Vascular tissue that transports water and minerals upward in plants.

Phloem

Vascular tissue that distributes dissolved food materials throughout the plant.

Ground Tissue

Tissue that provides support and storage in plants, consisting of parenchyma, collenchyma, and sclerenchyma.

Dermal Tissue

Protective outer covering of the plant that regulates gas exchange and water uptake.

Root

Plant organ responsible for anchorage and absorption of water and minerals.

Stem

Supports and conducts nutrients and water in plants.

Leaf

Organ responsible for photosynthesis and gas exchange.

Flower

Reproductive structure of flowering plants.

Seed

A ripened ovule containing an embryo and stored food supply.

Fruit

Mature ovary containing seeds and surrounding tissue.

Parthenocarpy

Production of fruit without fertilization, resulting in seedless fruit.

Simple Fruit

Develops from a single ovary of a flower.

Aggregate Fruit

Collection of simple fruits from a single flower.

Multiple Fruit

Develops from multiple flowers in an inflorescence.

Middle lamella

where pectin cements adjacent cells together

Cell wall, Cytoplasm, and Nucleus

Three main components of plant cell

Primary wall

thin, not rigid, stretched as the cell grows; layer formed before and during growth of the plant cell; consists of cellulose microfibril; plasmodesmata

cytoplasmic streaming/cyclosis

flowing movement of cytoplasm

Rough ER

involved in the synthesis of lipid

Smooth ER

involved in the synthesis of membrane proteins and secretory proteins

Outer membrane

permeable to smaller particles; contains the respiratory chain component and enzymes for ATP synthesis

Inner membrane

impermeable and folded into numerous cristae, and the site of espiration (energy source for plant’s body maintenance, growth, and development)

Chloroplast

site of photosynthesis; involved in amino and fatty acid synthesesrovides space for temporary starch storage