Unit 2 Flashcards
Reflex arcs in animals
1) voluntary responses (walking, eating, etc.)
2) Skeletal RA (foregoes the brain)
3) physiological reflex arcs (cardiac muscle. smooth muscle, glands, etc.)
Response to light
1) light -> cis retinal -> changes shape 2) trans retinal -> 3) opsin changes shape -> 4) activation of receptor ->5) g- protein activated -> 6) Ion channels close
rhodopsin
retinal molecule that changes shape when light hits (cis -> trans)
sensory
receiving from external and/or internal environment
Tropism
Bending in response to stimuli (+ towards, - away)
Plant stimuli
- light
- touch
- gravity
- temperature
- PH/Chemicals
- Water
- Wind
Animal Stimuli
- pheromones
- food (glucose, fat, protein)
- water
- temperature
- predators/danger
- light
Types of sensory receptors (plants)
Photoreceptors: Light
Thermoreceptor: Temp.
Chemoreceptor: PH/Chemicals/Food
Hydroreceptor: Water
Mechnoreceptor: Tropisms
Types of sensory receptors (animals)
Photoreceptor: Light
Thermoreceptor: Temp.
Chemoreceptor: Detect specific type (olfaction -> smell/gustatory -> taste)
Nociceptor: Pain/noxious
Taxis: movement (+ toward, - away)
Mechanoreceptor: gravity/positioning
electroreceptor: change in voltage
magnoreceptor: magnetic fields
Voluntary Response (animals)
Sensory neuron: receives info about internal and external environment and sends it to CNS
Afferent (arrives) neuron: conducts signal towards CNS
Motor neuron: responds to sensory info (skeletal mus.)
efferent (exit) neuron: conduct signal away from CNS
Reflex Arcs (animals)
Sensory Neuron (afferent)
Interneuron: entirely in the CNS that conveys information, bypass brain
Motor Neuron (efferent): responds to sensory information by control of skeletal muscles
Plant Phototropic response
Growth/response toward light
Rhodopsin -> GPRC -> detects light
Auxin impact on plant growth
decrease in auxin in presence of light
auxin efflux to shaded side produces increase in cell elongation
less auxin = protein produced
decrease in auxin and gene expression
