Stimulus and Response: Basic Flashcards
What is a STIMULUS?
-A DETECTABLE CHANGE in the INTERNAL or EXTERNAL ENVIRONMENT
-Of an ORGANISM that produces a RESPONSE
Why, generally, are RESPONSES produced by an ORGANISM
To ENHANCE the animals chances of SURVIVAL
What are some examples of a STIMULUS?
-LIGHT
-pH
-HUMIDITY
-TEMP
-PRESSURE
-PAIN
How would you describe KINESIS?
A NON DIRECTIONAL RESPONSE
How would you describe TAXIS?
-A DIRECTIONAL RESPONSE
-Determined by the DIRECTION OF the STIMULUS
What is PHOTOTAXES?
A LIGHT STIMULUS
What is CHEMOTAXES?
A CHEMICAL STIMULUS
What are TROPISMS?
-The GROWTH movement of a part of a PLANT
-In RESPONSE to a DIRECTIONAL STIMULUS
–>Usually AWAY/TOWARDS from STIMULUS
What is GEO/GRAVOTOPISM?
A STIMULUS caused by GRAVITY
What is HYDROTOPISM?
A STIMULUS caused by WATER
What are signs that a PLANT is GROWING? How is this linked to a TROPIC RESPONSE?
-FLOWERING-TALLER-ROOTS-NEW SHOOTS
-Plants grow TOWARDS/AWAY from a STIMULUS
Why do PLANTS respond to EXTERNAL STIMULI? BEETE
-Improve chances of SUCCESFUL BREEDING
-Avoid ENVIRONMETNAL STRESS e.g move to shade to avoid H2O LOSS
-Avoid being EATEN
-TROPISM (DIRECTIONAL GROWTH RESPONSE)
-ENHANCE SURVIVAL
What controls a PLANTS RESPONSE to an EXTERNAL STIMULUS?
HORMONES known as AUXINS CONTROL/COODINATE a plants RESPONSE
What is the HORMONE responsible for PHOTOTROPISM/GROTROPISM in PLANTS?
IAA- INDOLEACETIC ACID
What is the NAME of the MOLECULE and PROTEIN that DETECTS LIGHT in PLANTS?
-PHOTORECEPTOR
-PHOTOTROPIN
What PART of the plant DETECTS LIGHT STIMULUS?
Shoot Tips
What PART of the PLANT shows POSITIVE GEOTROPISM?
Roots
What PART of the PLANT shows NEGATIVE GEOTROPISM?
Shoot Tips
Which PART of the PLANT shows NEGATIVE PHOTOTROPISM?
Roots
Which PART of the PLANT shows POSITIVE PHOTOTROPISM?
Shoot Tips
What is the ENZYME responsible for LOOSENING the CELL WALL during PHOTOTROPISM?
Expansin
What is the ORGANELLE in PLANTS that allow the MOVEMENT OF WATER?
Aquaporin
If there is a LOW CONCENTRATION of INDOLEACETIC ACID in the ROOTS, what happens?
ELONGATION in the ROOTS
If there is a HIGH CONCENTRATION of INDOLEACETIC ACID in the SHOOT TIPS, what happens?
ELONGATION in the SHOOT TIPS
