Forces in Nature

Forces in Plants

(Top part of flap)Turgor Pressure – internal water pressure that prevents wilting and provides support.-----------------------------------------------------------------------------Tropisms: Growth Responses

- Phototropism – growth towards light- Geotropism – roots grow with gravity –

stem away- Hydrotropism – roots grow towards water

-----------------------------------------------------------------------------Seedling Emergence – seedling stem tip pushes away from gravity to reach sunlight above the ground.

Turgor Pressure (wilting)

(low turgor pressure) (high turgor pressure)

Phototropism The plant is

growing towards the

light

Stem grows opposite gravity and roots grow with gravity

Geotropism Seedling Emergence

Internal Stimuli (this is on the top flap)

Internal Stimuli in animals – the body responds to maintain balance

Sneezing

Our response when germs and other foreign invaders have entered your body

Fever

Our bodies raise their temperatures to fight germs and other foreign invaders

Animals may vomit to rid

themselves of internal

contamination

Internal Stimuli in Plants

Internal Stimuli (this is on the bottom flap)

Animals’ responses to External Stimuli

External Stimuli (this is on the top flap)

REFLEX – an action that is performed without conscious thought as an automatic response to a stimulus.Example: a

person moves their leg instantly

when the tendon by

their knee is struck

FIGHT or FLIGHT – an animals response to a threatening situation

FIGHT FLIGHTor

Plants’ Responses to External Stimuli

External Stimuli (this is on the bottom flap)

Growing towards it

is the response.

The Sun is the

stimulus.

PHOTOSYNTHESIS

Plants use the Sun’s radiant energy to make sugar. Energy is stored as food (chemical energy), while releasing O2.Animals do the

opposite. We use that chemical energy converting it to movement and heat, while releasing CO2 and H2O.

Phototropism Time lapse (corn)

Phototropism Time lapse (tomato)