Plant Anatomy & Function

What are meristematic tissues?

Plant tissues made of actively dividing cells that produce new growth for the plant.

What is apical meristem?

Tissue at root and shoot tips that makes the plant grow longer (primary growth).

What is lateral meristem?

Tissue that makes the plant grow thicker by producing wood (secondary growth).

What is intercalary meristem?

Tissue in grasses that allows fast regrowth after cutting or damage.

What is dermal tissue?

Outer protective layer of the plant that helps prevent water loss and protects from damage.

What is ground tissue?

Tissue that carries out photosynthesis, stores nutrients, and provides support.

What is vascular tissue?

Transport system of the plant that moves water, minerals, and sugars.

What is palisade mesophyll?

Layer of tightly packed cells in leaves where most photosynthesis happens.

What is spongy mesophyll?

Layer with air spaces that allows gases like CO₂ and O₂ to move easily.

What are stomata?

Tiny pores on leaves that allow gas exchange (CO₂ in, O₂ and water out).

What is a monocot?

A plant with 1 seed leaf, parallel veins, fibrous roots, and flower parts in 3s.

What is a dicot?

A plant with 2 seed leaves, net-like veins, taproots, and flower parts in 4s or 5s.

What is xylem?

Vascular tissue that moves water and minerals from the roots up to the rest of the plant.

What is phloem?

Vascular tissue that moves sugars (food) made in leaves to the rest of the plant.

Are xylem cells alive?

No, they are dead to form hollow tubes so water can flow freely without obstruction.

Are phloem cells alive?

Yes, because they need energy from companion cells to actively transport sugars.

What are tracheids and vessel elements?

Xylem cells that form tubes to carry water through the plant.

What are sieve-tube elements and companion cells?

Phloem cells that move sugars and are supported by companion cells.

Which direction does xylem transport go?

Only upward, from roots to leaves.

Which direction does phloem transport go?

Both directions, depending on where sugars are needed (source to sink).

What are stomata?

Tiny openings in leaves that control gas exchange and water loss.

What are guard cells?

Cells that open and close stomata depending on water levels.

What is transpiration?

The loss of water vapor from leaves through stomata.

Why is transpiration important?

It creates a pulling force that moves water from roots up through the plant.

What is photosynthesis?

The process where plants use sunlight, water, and CO₂ to make glucose (food).

What do plants need for photosynthesis?

Light energy, water, and carbon dioxide.

What are angiosperms?

Flowering plants that reproduce using flowers and seeds.

What is pollination?

The transfer of pollen from the male part of a flower to the female part.

What are the types of pollination?

Self-pollination, wind pollination, and animal/insect pollination.

Why do plants use animals for pollination?

To increase the chances of successful reproduction.

How do plants know when to flower?

They measure the length of night using light-sensitive pigments.

What are phytochromes?

Light-detecting pigments that help plants track day and night length.

Why are phytochromes important?

They help plants know when the seasons are changing so they flower at the right time.

What are short-day plants?

Plants that flower when nights are long (usually fall or winter conditions).

What are long-day plants?

Plants that flower when nights are short (usually spring or summer conditions).

What are plant hormones?

Chemical signals that control plant growth and responses.

What is auxin?

A hormone that controls plant growth direction, especially toward light.

What are gibberellins?

Hormones that help plants grow taller and start seed germination.

What are cytokinins?

Hormones that promote cell division and make plants grow more branches.

How does auxin affect shoots?

It makes shoot cells grow longer, helping the plant grow upward.

How does auxin affect roots?

It slows cell growth, causing roots to bend downward.

What is ethylene?

A plant hormone that is a gas and controls ripening and aging.

What does ethylene do?

It makes fruit ripen and causes leaves and fruit to fall off.