Lectures 27-28 Flashcards
(26 cards)
What does NOT happen when you feel scared:
A. Heart rate decreases
B. Pupils dilate (expand)
C. Blood supply to muscles increases
D. Hairs raise on the back of your neck (piloerection)
E. Your respiration rate increases
A. Heart rate decreases
What is the primary role of adrenaline (epinephrine) in the body?
Adrenaline activates ‘flight mode’ in response to stimuli.
This is part of the body’s stress response mechanism.
What does the pituitary gland release to signal the adrenal gland?
Chemical signals.
This initiates the release of adrenaline into the bloodstream.
What is the effect of adrenaline on heart rate?
Increases heart rate by binding to ‘pacemaker cells’.
This response is crucial during stressful situations.
How does adrenaline affect muscle cells?
Makes them contract.
This prepares the body for physical exertion.
What happens to blood vessels when adrenaline binds to surrounding cells?
It can cause constriction or dilation to control blood supply.
This helps redirect blood flow to essential organs.
Cell signaling involves which two key components?
Ligands and receptors.
Ligands are signaling molecules that bind to receptors to trigger cellular responses.
Fill in the blank: The adrenal gland releases _______ into the bloodstream.
adrenaline
True or False: Adrenaline only causes dilation of blood vessels.
False
Adrenaline can cause both constriction and dilation depending on the type of receptor activated.
What is the first step in the process of adrenaline release?
Signaling in the brain activates ‘flight mode’.
This is triggered by perceiving a threat or stimulus.
What are the two main components involved in cell signaling?
Ligands and receptors
Ligands are molecules that bind to receptors to initiate signaling.
Define ligand in the context of cell signaling.
A ligand is a signaling molecule that binds to a receptor protein.
What is a receptor protein?
A receptor protein is a molecule on a cell that binds to a ligand.
What initiates the process of signal transduction?
The ligand-receptor interaction initiates the process of signal transduction.
Fill in the blank: Signal transduction is the pathway through which a signal is converted to _______.
cellular responses
What is signal transduction?
Signal transduction is the process through which a signaling molecule binds to a signaling molecule pathway to convert signals into cellular responses.
What are the three main stages of a generic signal transduction pathway?
- reception 2. transduction 3. response
These stages represent the process by which cells respond to external signals.
4 types of signaling in animals
endocrine
synaptic
contact-dependent
paracrine
What is the general principle of cell signaling?
External signals are converted to responses within the cell
This highlights the fundamental process of how cells communicate and respond to their environment.
What are the key players in signal transduction?
- G-protein coupled receptors
- G-proteins
- Second messengers
These components work together to relay signals from outside the cell to elicit a response.
What is an example of signal transduction mentioned in the lecture?
Taste transduction
This example illustrates how taste signals are processed by the body.
What do G-protein coupled receptors (GPCRs) contain?
Seven transmembrane domains
This structural feature is essential for their role in signal transduction.
Fill in the blank: __________ are molecules that mimic ligands.
Cholesterol
Cholesterol can influence the function of GPCRs by mimicking signaling molecules.
