Seed Structure

Embryo: Develops into a new plant

Cotyledon: Stored food that the plant uses before it begins photosynthesis (develops into 1st leafs)

Testa: Seed coat protecting the embryo (can vary in thickness)

Germination

The sprouting of a seedling from a seed.

1. Water is absorbed & activates the plant embryo cells.

2. The embryonic plant begins to synthesize gibberellin (plant hormone that stimulates mitosis & cell division, activates amylase production).

3. Gibberellins cause the synthesis of amylase.

4. Amylase hydrolyzes starch being stored in the cotyledon, producing maltose.

5. Maltose is absorbed by the plant embryo.

6. Maltase digests maltose, producing glucose (which is used in cellular respiration to create ATP to fuel plant growth).

Lestat beginning 

to sprout: stems are growing

upwards & cotyledons are

lifting out of the soil.

Radicle

First leaves

Cotyledons

Terminal bud: New shoot growth

Node: Where leaves/buds attach

Bud: Grow into branch/flower

Cotyledon: Stored food

Tap root: Anchor & water access

Lateral root: Increase absorption 

Hairs: Boost water/mineral absorption

Leaf: Photosynthesis & gas exchange

Dermal tissue: Protective outer layer

Cuticle tissue: Waxy coat that reduces water loss

Meristems: Regions from which a plant can grow

Apical: Causes primary growth (up & down, length), is located at the tips of shoots & roots, produces new leaves, flowers, and roots

Lateral: Causes secondary growth (widening), located in the stem of the cambium, produces cork & bark 

Ex: Vascular cambium in trees

Shoot apical meristem

Lateral meristem (inside)

Auxin: influences cell growth rates by changing gene expression; in the shoot apical meristem it promotes growth & division so the plant will grow taller, it prevents growth & division @ nearby axillary buds

Gibberellin: Stimulates mitosis & cell division in the embryo; activates production of amylase 

Phototropism: Light receptors trigger the redistribution of auxin to the dark side of th plant, causing the dark side of the shoot to elongate and the shoot to grow towards the light

Dark side

Side that gets light

Pods started to grow

Lestat started to flower & grew much taller, along with some new leaves

1. Mineral ions are actively transported into the roots (low to high)

2. Water enter the roots by osmosis passively thru membrane or channel protein (hypotonic to hypertonic)

3. Water is transported thru xylem tissue (vascular tissue) that transports water & dissolved mineral ions from roots to leaves

4. Cohesion & adhesion maintain a chain of water in the xylem, froom roots to leaves

5. Water evaporates from leaves thru stomata (typically open during the day so the plant can get the CO2 needed for photosynthesis; H2O evaporates when the stomata are open, pulling the chain of water up the xylem)

6. The rate of transpiration depends on abiotic factors 

Transpiration/Evaporation Process

*Xylem is made of dead cells, only the cell wall remains (made of cellulose & lignin) which provide rigidity & strength to to the plant that allows for upright growth