Homeostatis and Hypothalamus 2 Flashcards
(37 cards)
What are organ reflexes loops?
Internal organs have intrinsic control mechanisms. Can operate at a baseline level on their own BUT organ reflexes can’t adjust to changes.
What is an example of organ reflexes loops?
Heart has built in “pacemakers” to regulate heartbeat. Heart will pump on its own at about 110 beats per minute. Heart automatically pumps harder when filled with larger amount of blood. BUT the automatic pumping would fail to adapt if person stood up or started to run.
Goosebumps.
What is local reflex loops?
Oragans send/receive info to spinal cord creating reflex loops. Oragan and spinal cord can adapt organ functioning to local needs.
Organs of homeostatic organization : Respiration
Oxygen is required ti fuel our metabolism by burning glucose. The waste product of cellular respiration is carbon dioxide.
What do lungs do?
They regulate intake alf oxygen and expelling of carbon dioxide.
Organs of homeostatic organization : Blood Glucose
Must regulate levels of glucose available to the body.
What does the pancreas do?
It detects glucose levels. Releases insulin when glucose levels are too high (extra glucose get stored). Releases glucagon when glucose levels are too low (to free up stored glucose)
What does the drug ozempic do?
It is used to lose weight and was designed to regulate blood sugar levels.
Organs of homeostatic organization : Water Regulation
Proper hydration is needed to transport material throughout the body.
What do the kidneys do?
Monitor and regulate levels of water in the blood. When water levels are low, kidney reduces amount of water in urine to keep the blood water levels higher.
Organs of homeostatic organization : Thermoregulation
Must regulate body temperature for optimal metabolism. The biochemical reactions like enzyme activity impact by temperature.
What happens when a person gets too hot?
Sweat glands are activated to cool down the body.
What happens when a person gets too cold?
Muscles shiver to raise body temperature. Getting goosebumps is an example of organ reflex.
What is the pilomotor reflex?
tiny muscles attached to hair follicles contract in response to the cold. Hair standing up may trap warm air around the body (evolutionary leftover)
What other time can pilomotor reflex be triggered?
can be triggered by activation of sympathetic nervous system.
Where does the spinal cord run through?
Runs through a space at the back of the backbone called the vertebral foramen.
Where does the spinal cord end?
It ends at the lumbar area.
Where is the grey matter and white matter located in the spinal cord?
The center of the spinal cord is filled with grey matter (cell bodies) and surrounded by white matter (axons, nerves).
The somatic Nervous System.
Conscious and Voluntary
“Skeletal Nervous System”
Sensory and Motor neurons
Motor neuron directly connects to muscle
What do the sensory and motor neurons do?
They send info to CNS (spinal cord and brain)
Motor neurons from CNS directly connect to a specific set of muscle fibers.
Allows very precise control
Axons are well myelinated. Conducts signals rapidly.
The Autonomic Nervous System.
Unconscious and Involuntary.
Sympathetic and Parasympathetic.
Also has sensory and motor neurons
Sensory info from internal organs sent to brainstem. Remains unconscious. Axons are not well myelinated. Conducts signals slowly.
Motor neuron connects to ganglia.
What does the Ganglia do?
Ganglia “relays” signal to the muscle.
What does the autonomic nervous system innervate?
Cardiac muscles, smooth muscle, and glands. Internal organs often contain “smooth muscle” such as stomach, intestines, badder, blood vessels, kidneys
What does the autonomic nervous system regulate?
The internal organs and
The metabolic functions and physiology.
Heart rate, respiration, blood pressure, digestion, urination, glucose storage/use, body temperature.
