MAB Unit 6 Final Vocab

Vascular Plant

Plants that possess "true" roots, leaves, and stems, along with specialized vascular tissues (tubes) to transport water and food throughout the organism

Nonvascular Plant (aka Bryophyte)

Plants that lack specialized tubes for moving water and nutrients, instead relying on osmosis; they do not have true leaves, stems, or roots, using structures called rhizoids to anchor themselves to the ground

Pteridophyte (ferns

A type of seedless vascular plant that reproduces via spores

Gymnosperm

A category of seeded vascular plants, often called "naked seed" plants, that produce seeds directly on the surface of cones rather than inside a fruit

Angiosperm

Seed-producing vascular plants, also known as flowering plants, that produce seeds enclosed within a protective tissue that develops into a fruit

Cotyledon

Often referred to as a "baby leaf" or "seed leaf," it is the initial leaf found inside a plant embryo within a seed

Monocot

A group of angiosperms characterized by having one cotyledon in their embryos, parallel leaf veins, and fibrous roots

Dicot

A group of angiosperms characterized by having two cotyledons in their embryos, webbed/net-like leaf veins, and taproots

Xylem

Vascular tissue responsible for moving water and dissolved minerals upward from the roots to all other parts of the plant

Phloem

Vascular tissue that carries nutrients and food (sugars) made in the leaves to the rest of the plant

Dermal Tissue

The outer protective layer of a plant used for protection and to prevent water loss

Epidermis

The outermost layer of cells in the dermal tissue used to protect the plant

Cuticle

A waxy coating on the surface of leaves and stems that prevents water loss and provides protection

Stomata

Pores, typically located on the lower epidermis of leaves, that allow gases to enter and exit the plant

Ground Tissue

Any plant tissue that is not dermal or vascular; it is used for metabolism, storage, and support

Collenchyma

A type of ground tissue that provides support using cells with thick cellulose walls

Sclerenchyma

A durable ground tissue that is often "woody" and strengthened by lignin; these cells may be dead at maturity

Parenchyma

Traditional plant cells used for metabolic functions, photosynthesis, and storage

Cortex

A region of ground tissue located between the epidermis and the vascular tissue in roots and stems

Shoot System

The part of the plant organ system typically above the soil line, including stems and leaves

Shoot Apical Meristem

Meristematic tissue located at the tips of stems responsible for producing new cells for upward growth

Terminal Bud

Identified in diagrams as the apical bud, it is the bud located at the very tip of a shoot

Axillary Bud

Identified in diagrams as a lateral bud, it is a bud that grows from the axil (the angle between a leaf and the stem)

Leaf

The primary plant organ responsible for making food through photosynthesis

Blade

The main, flat part of a leaf

Internode

The section of a plant stem located between two nodes

Root System

The part of the plant organ system, usually below the soil line, responsible for absorbing water and minerals

Root Apical Meristem

Meristematic tissue found at the tips of roots involved in downward growth

Root Tip

The growing end of a root which contains the apical meristem and is protected by the root cap

Root Cap

A protective structure located at the very end of the root apex

Root Hair

Small extensions of the dermal tissue on roots that increase surface area for water and mineral absorption

Phototropism

The tendency of a plant to grow toward (positive) or away from (negative) a light source

Gravitropism

A plant's growth response to the pull of gravity; stems show negative gravitropism (grow up), while roots show positive gravitropism (grow down)

Thigmotropism

The tendency of plants to grow around or respond to objects they come into contact with

Auxin

A hormone that promotes cell elongation, controls apical dominance, and drives phototropism and gravitropism

Ethylene

A gaseous plant hormone that stimulates fruits to ripen and causes abscission (the dropping of leaves, flowers, and fruits)

Cytokinin

A hormone that stimulates cell division (cytokinesis), promotes seed sprouting, and delays the aging of leaves

Abscisic Acid

A hormone that inhibits growth during periods of stress, closes stomata to prevent water loss, and causes leaf drop

Gibberellin

A hormone that causes dramatic increases in plant size, promotes rapid growth in stems and leaves, and breaks seed dormancy