BIOL 207 Lecture Notes - Lecture 17: Cerebro, Fluid Compartments, Central Nervous System
Homeostasis (pg 8-12)
• is the oditio i hih ithi liits the od’s iteral eiroet or ilieu iteri
remains relatively constant. (**can statement**)
• OR
• a state of dynamic equilibrium of the internal environment
Fluid compartments (pg 999) (*body is 60% water*)
• ICF (Intra Cellular Fluid): fluids inside of the cell (40%)
• ECF (Extra Cellular Fluid): these are fluids located outside the cells and it is the ECF that
represents the internal environment (20%)
• Intercellular/interstitial/tissue fluids: this is where the exchange occurs, capillaries travel will
release the goods gluose, horoes, sodius, hlorides, itais ad the goods/itais leae the
capillaries and diffuse into the interstitial spaces and commingle with the extra cellular fluids, and from
there the goodsaterials ill go to the ells, at the sae tie the aste produts ad uated
materials leave the cells, go into the interstitial fluids, and ultimately make their way back into the
capillary as its going out. This represents a major component of the internal environment.
• Blood plasma of the CVS (cardiovascular system)/the lymph: fluid given in the lymphatic system,
which consists only of veins, meaning all they are doing is picking up excess fluid, all of this is percolating
back from the extremities and making their way back to major blood vessels in the CVS, and dumping
that back into the CVS.
• Cerebro Spinal Fluid of the Central Nervous System: brain/spinal cord meninges are 3 connective
tissue layers. one adheres to the surface of the brain and spinal cord (not called visceral), find the fluid in
between the membranes, also in the ventricles or the brain and the spinal cord there is a canal that has
cerebro spinal fluid
Stress and Homeostasis (pgs 8-11)
• homeostasis in individuals is constantly stressed by various stressors.
• Stress: any stimulus or circumstance that creates an imbalance in the normal internal
environment.
• three major sources of stress
• infection
• poison
• extreme exposure
• ***fournatley the body has many control or regulatory mechanisms (homeostatic mechanisms)
that oppose the forces of stress and bring the internal environment back into balance. (pgs 9/10, figures
1.4, 1.5)
• these homeostatic controls usually include 3 components
• a receptor (A)
• a control center (B)
• an effector (C) (muscles and glands)
• the imbalance creates a stimulus and the receptor (A) senses or picks up this change and sends
it along the afferent pathway to the control center. the control center (B) sends an output of
find more resources at oneclass.com
find more resources at oneclass.com
Document Summary
Is the (cid:272)o(cid:374)ditio(cid:374) i(cid:374) (cid:449)hi(cid:272)h (cid:862)(cid:449)ithi(cid:374) li(cid:373)its(cid:863) the (cid:271)od(cid:455)"s i(cid:374)ter(cid:374)al e(cid:374)(cid:448)iro(cid:374)(cid:373)e(cid:374)t or (cid:373)ilieu i(cid:374)teri(cid:373) Homeostasis (pg 8-12) remains relatively constant. (**can statement**) Or a state of dynamic equilibrium of the internal environment. Icf (intra cellular fluid): fluids inside of the cell (40%) Ecf (extra cellular fluid): these are fluids located outside the cells and it is the ecf that. Intercellular/interstitial/tissue fluids: this is where the exchange occurs, capillaries travel will capillary as its going out. This represents a major component of the internal environment. which consists only of veins, meaning all they are doing is picking up excess fluid, all of this is percolating. Stress: any stimulus or circumstance that creates an imbalance in the normal internal. Stress and homeostasis (pgs 8-11) environment. that oppose the forces of stress and bring the internal environment back into balance. (pgs 9/10, figures.
