Animal Response to the Environment Flashcards
cellular receptors (2)
can be found in:
- membrane
- cytoplasm
how can amplification occur during transduction (2)
- one molecule can activate many other molecules as long as it stays active, and those can activate other molecules
- a single transcription factor can create many mRNAs
responses to reception of signal (2)
- change in gene expression
- change in structure of existing molecules
transduction
- converts incoming signal into a form that can cause a response in the cell
how can high temperatures damage cells
- it denatures proteins of the cell so that they cannot form their original function
molecule chaperone proteins (3)
quality control system for proteins
- assist in protein folding and refolding
- prevent protein aggregation
- target proteins for degradation
regulation of heat shock proteins (hsp) (4)
- at rest, proteins found in a multiprotein complex
- cellular stress causes complex to dissociate and become active:
- released hsp perform their chaperone functions
- released HSF acts as a TF to up-regulate hsp expression
HSF mechanism (4)
- released HSF forms a trimer with other HSF molecules
- enters the nucleus
- acts as a TF
- up-regulates production of hsps
heat shock pathway: receptor
- cellular stress: causes complex to dissociate
heat shock pathway: transduction
- trimerization of HSF and HSF acting as a TF
heat shock pathway: response
- hsps refold denatured proteins and help prevent protein aggregation
nervous system (2)
- complex network of specialized cells (neurons) that transmit signals
- often coordinated by groups of neurons, such as brain and ganglia
how does the nervous system transmit signals (2)
- transmit electrical signals across long distances WITHIN cells
- short distance signalling (paracrine) BETWEEN cells at the synapse
endocrine system (2)
- series of organs (endocrine glands) that release hormones into the blood
- detected by receptors on the target cells
juxtacrine
- cells next to each other communicate directly
paracrine
- nearby cells communicate by releasing chemicals that can act on oneself or on neighbours
endocrine
- cell communicate throughout the whole body by releasing hormones into the blood
signalling pathway of the nervous system: receptor
- sensory receptors that are triggered by incoming stimuli
signalling pathway of the nervous system: transduction
- afferent neurons send signal to integrating center
- integrating center sends signal to efferent neurons
signalling pathway of the nervous system: response
- signal from efferent neuron causes effector organs to produce some output
the stress response (2)
coordinated by both nervous system and the endocrine system working together:
- sympathetic nervous system
- HPA axis
the stress response signalling pathway: transduction (3)
- signals that were received are sent to the CNS
- brain processes the signals
- activation of sympathetic nervous system or HPA axis
why does evolution shape us to be scared first, before thoroughly accessing the threat
- better to be safe, than sorry
what kind of activities do the sympathetic system regulate
fight or flight activities
effects of circulating epinephrine (4)
- increased heart rate
- bronchodilation
- decreased blood flow to the gut and kidney
- increased blood flow to the muscle
how long does it take for the effects of circulating epinephrine to happen
happens in seconds - minutes
cortisol signalling pathway (3)
- binds to intracellular receptor
- receptor is translocated to the nucleus
- receptor binds to DNA and acts as a transcription factor
acute stress response
- fight or flight helps deal with short-term stressors and to recover from intense effects of response
chronic stress effects (4)
- memory loss and lack of concentration
- immune suppression
- weight gain/loss
- IBS, infertility, etc (messes with other hormones)
chronic stress effect on the brain
- neurons in cortex and hippocampus get smaller (thinking and memory)
- neurons in amygdala get larger (fear and anxiety)
