Interactions Among Plant SystemsBiology 10(B)

Learning objectives• Identify major systems in plants• Describe the interactions that occur among

systems to carry out vital plant functions

Interactions Among Plant Systems

• Organ systems:– Shoot system – above-

ground – Root system – below-

ground

• Tissue systems:– Dermal – barrier– Ground – metabolic

functions– Vascular – transport

Plant Systems

Shoo

t sys

tem

Roo

t sys

tem

DermalGround

Vascular

Tissues

Organ and tissue systems interact to carry out vital functions• Transport• Reproduction• Response

Interactions Among Plant Systems

• Movement of needed materials throughout plant

• Major function of vascular tissue– Xylem – transports

water and minerals– Phloem – transports

glucose– Both transport

hormones

Transport

Interactions during transport• Root system– Absorbs water and minerals

• Shoot system– Ground tissue produces glucose through

photosynthesis• Both organ systems– Produce hormones– Vascular tissue transports all materials

throughout the plant

Interactions Among Plant Systems

Vegetative propagation – offspring produced from part of a plant organ• Asexual

Pollination – offspring produced via pollinated seeds • Sexual

Reproduction

Image by Roberto MM [GFDL]

• Flower – organ that produces seeds

• Fruit – develops around fertilizedovule(s)

• Seed – fertilized ovule (embryo) and stored food (cotyledon) surrounded by a protective seed coat

Reproduction by Pollination

Interactions during reproduction• Vegetative propagation– Shoot and root systems: part of an organ

produces a new plant• Pollination– Shoot system: flowers are the site of seed

pollination and fruit development– Shoot and root systems: produce hormones,

transported by the vascular tissue, that regulate flower budding, fruit ripening and seed growth

Interactions Among Plant Systems

• Tropisms – plant’s hormonal growth response toward or away from an external stimulus

• Examples:– Phototropism – stem and leaves grow toward a

light source– Positive gravitropism – roots grow toward gravity

(downward)– Negative gravitropism – stem and leaves grow

away from gravity (upward)

Response

Interactions during response• Root system– Grows toward gravity

• Shoot system– Grows toward light and/or away from gravity

• Both systems– Produce hormones – Transported hormones

Interactions Among Plant Systems

Learning objectives• Identify major systems in plants• Describe the interactions that occur among

systems to carry out vital plant functions

Interactions Among Plant Systems