(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 GeotropismSeedling Emergence

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

Animals’ responses to External Stimuli 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 FIGHTFLIGHTor

Plants’ Responses to External Stimuli Growing towards it is the response. The Sun is the stimulus.

Plants use the Sun’s radiant energy to make sugar. Energy is stored as food (chemical energy), while releasing O 2. Animals do the opposite. We use that chemical energy converting it to movement and heat, while releasing CO 2 and H 2 O.

Phototropism Time lapse (corn) Phototropism Time lapse (tomato)