Botany exam 2

What are the parts of a seed and their functions?

Seed coat (protection), embryo (growth), cotyledons (nutrients), endosperm (food).

What do RAM and SAM do in plants?

Supports primary root and shoot growth.

Define 'meristem.'

Region of active plant cell division, enabling growth.

Define 'senescence.'

The process of aging and death in plant tissues.

What are the regions of a root and their functions?

Root cap (protection), cell division, elongation, and maturation.

How does the root cap relate to gravity sensing?

It detects gravity, guiding roots downward.

How do roots grow via the root apical meristem?

Root apical meristem continuously forms new cells for growth.

What is the anatomy of a root?

Epidermis, cortex, endodermis, pericycle, vascular cylinder, and pith.

How are lateral roots formed?

They develop from the pericycle in mature roots.

Describe the node and internode pattern in stems.

Nodes hold leaves; internodes are spaces between nodes.

What is the role of the shoot apical meristem in stems?

It drives primary growth of the stem.

Differences between monocot and dicot stem anatomy?

Monocots: scattered bundles; dicots: ringed bundles.

What are the main structures in stem anatomy?

Epidermis, cortex, vascular bundles, xylem, phloem, pith.

How are leaves formed by the SAM?

SAM produces leaf primordia for leaf development.

What are types of leaf arrangement and venation?

Alternate, opposite, whorled; venation: parallel, reticulate.

What are simple vs. compound leaves?

Simple: one blade; compound: multiple leaflets per leaf.

What is the function of stomata?

They control gas exchange and water loss.

Describe internal leaf anatomy.

Vascular bundles and mesophyll layers (spongy, palisade).

What is the role of xylem and phloem?

Xylem transports water; phloem transports nutrients.

What do vascular cambium and cork cambium produce?

Vascular: secondary xylem/phloem; cork: protective bark.

How can growth rings determine stem age?

Annual rings indicate years of growth in woody stems.

What are the layers of bark, living and dead?

Living inner bark; dead outer layers.

Define tendril and aerial roots.

Tendrils support; aerial roots absorb moisture from the air.

How does light affect leaf structure?

Light availability influences leaf thickness and orientation.

Difference between spines, prickles, and thorns?

Spines: modified leaves; prickles: epidermal; thorns: modified stems.

What is the Cohesion-Tension Theory?

Theory that water moves up xylem via cohesion, adhesion, tension.

Define transpiration and cavitation.

Transpiration: water loss via leaves; cavitation: air bubble formation.

How does phloem transport photosynthesis products?

Moves sugars from source (leaf) to sink (root/fruit).

What processes do plants perform?

Plants perform respiration and photosynthesis.

Key steps and products of respiration and photosynthesis?

Respiration: energy release; photosynthesis: sugar and oxygen production.

Why are leaves green?

Chlorophyll absorbs red/blue light, reflecting green.

What are the six mineral macronutrients?

Nitrogen, phosphorus, potassium, calcium, magnesium, sulfur.

Define mobile and immobile nutrients.

Mobile moves within plant; immobile stays in place.

How do plants respond to the environment?

Plants adapt via growth and movement responses.

How does auxin affect directional growth?

Auxin promotes growth towards light (phototropism).

How do plants move through growth and turgor pressure?

Growth and cell expansion alter plant position.

Define phototropism, gravitropism, thigmotropism, and photoperiodism.

Growth toward light, gravity, touch; response to day length.

What are warning signs of a plant's chemical defenses?

Bitter taste, strong smell, or toxicity to herbivores.

Epidermis

outer covering derived from protoderm

Cortex

structural and storage tissues derived from the ground meristem

Vascular Cylinder / Stele

vascular tissues derived from the procambium

Endodermis

inner boundary of cortex, encircles the vascular cylinder