HLSC 2410 EXAM 1 QUESTIONS AND ANSWERS WITH
COMPLETE SOLUTIONS VERIFIED LATEST UPDATE
What is homeostasis?*
Maintaining a stable internal environment necessary for life
How is the body organized?*
Cells -> Tissues -> organs -> organ systems
What is the estimated total amount of water in the body?
60% of the body weight
2/3rds of the body's water is located where?**
Inside the cells, Intracellular fluid
Where is the other 1/3rd of the body's water located?*
Outside of the cells, extracellular fluid
What are the 2 components of the extracellular fluid?
Plasma and Interstitial fluid
What is plasma?*
the extra cellular fluid within the blood cells
What is interstitial fluid (ISF)?*
fluid surrounding the cells within the rest of the tissues in the body
What separates the fluid inside the cells (ICF) from the extracellular fluid?*
The plasma membrane of the cells
What separates plasma from the interstitial fluid (ISF)?*
,The walls of blood vessels
Where does fluid exchange between the plasma and the interstitial fluid take
place?*
At capillaries
What is the ECF high in compared to the inside of the cell?**
Na+, Cl-, Ca+
What is the ECF low in compared to the inside of the cell?*
K+
How does the nervous system communicate?
Via neurotransmitters released by neurons
What does the nervous system consist of?*
Brain, spinal cord, and peripheral nerves
What does the endocrine system do?*
the glands secrete hormones into the circulatory system (blood)
How does the endocrine system communicate?
Via hormone released by cells of glands
Autocrine signaling
"self" signaling
Paracrine signaling
"next to"
What is a regulated variable?
variable that body works to keep up with normal range
What is a set point?
,range of normal values for regulated variables
What is a sensor/receptor?
component that detects change in regulated variable
What does afferent signaling mean?
signals are sent from body to the brain/ spinal cord (incoming)
ex. sensory
What does efferent signaling mean?
signals are sent from brain/spinal cord to the body (outgoing)
ex. motor
What is the integrating center?*
Where incoming signals are processed in the brain.
What does the integrating center do?
It compared values to the set point and relays adjustments to the efferent pathway to
bring regulated variables back to normal
What is the key process for maintaining homeostasis in physiology?*
Negative feedback
What is the overall goal of negative feedback?*
Maintain a physiological variable within a range of normal values
What does the process of negative feedback do?*
Corrects for deviations from a normal range of values and returns the variables back to
normal
How does negative feedback work?*
, It keeps a variable within a normal range by triggering a response that changes the
variable in the opposite direction as the original stimulus
What does the efferent pathway do in negative feedback?*
Sends signals to effector organs to cause changes in organ activity that returns
regulated variable back towards normal
What does positive feedback do?*
Reinforces the original stimulus, causing an even greater change and a stronger
response
What is the central theme of physiology?
homeostasis
What are the functions of cell membranes?
- separate or compartmentalize ions and molecules
- detect chemical signals from other cells
- link adjacent cells together via membrane junction
What does a selective barrier do?
Only lets in certain molecules and restricts the movements of other molecules
What affects a chemicals ability to move across the cell membrane?*
It's water solubility
What population has the least amount of water present in the body?
Obese people, about 45%
When are polar bonds formed?
When atoms at each end of the bond have an opposite charge
When are non-polar bonds formed?
COMPLETE SOLUTIONS VERIFIED LATEST UPDATE
What is homeostasis?*
Maintaining a stable internal environment necessary for life
How is the body organized?*
Cells -> Tissues -> organs -> organ systems
What is the estimated total amount of water in the body?
60% of the body weight
2/3rds of the body's water is located where?**
Inside the cells, Intracellular fluid
Where is the other 1/3rd of the body's water located?*
Outside of the cells, extracellular fluid
What are the 2 components of the extracellular fluid?
Plasma and Interstitial fluid
What is plasma?*
the extra cellular fluid within the blood cells
What is interstitial fluid (ISF)?*
fluid surrounding the cells within the rest of the tissues in the body
What separates the fluid inside the cells (ICF) from the extracellular fluid?*
The plasma membrane of the cells
What separates plasma from the interstitial fluid (ISF)?*
,The walls of blood vessels
Where does fluid exchange between the plasma and the interstitial fluid take
place?*
At capillaries
What is the ECF high in compared to the inside of the cell?**
Na+, Cl-, Ca+
What is the ECF low in compared to the inside of the cell?*
K+
How does the nervous system communicate?
Via neurotransmitters released by neurons
What does the nervous system consist of?*
Brain, spinal cord, and peripheral nerves
What does the endocrine system do?*
the glands secrete hormones into the circulatory system (blood)
How does the endocrine system communicate?
Via hormone released by cells of glands
Autocrine signaling
"self" signaling
Paracrine signaling
"next to"
What is a regulated variable?
variable that body works to keep up with normal range
What is a set point?
,range of normal values for regulated variables
What is a sensor/receptor?
component that detects change in regulated variable
What does afferent signaling mean?
signals are sent from body to the brain/ spinal cord (incoming)
ex. sensory
What does efferent signaling mean?
signals are sent from brain/spinal cord to the body (outgoing)
ex. motor
What is the integrating center?*
Where incoming signals are processed in the brain.
What does the integrating center do?
It compared values to the set point and relays adjustments to the efferent pathway to
bring regulated variables back to normal
What is the key process for maintaining homeostasis in physiology?*
Negative feedback
What is the overall goal of negative feedback?*
Maintain a physiological variable within a range of normal values
What does the process of negative feedback do?*
Corrects for deviations from a normal range of values and returns the variables back to
normal
How does negative feedback work?*
, It keeps a variable within a normal range by triggering a response that changes the
variable in the opposite direction as the original stimulus
What does the efferent pathway do in negative feedback?*
Sends signals to effector organs to cause changes in organ activity that returns
regulated variable back towards normal
What does positive feedback do?*
Reinforces the original stimulus, causing an even greater change and a stronger
response
What is the central theme of physiology?
homeostasis
What are the functions of cell membranes?
- separate or compartmentalize ions and molecules
- detect chemical signals from other cells
- link adjacent cells together via membrane junction
What does a selective barrier do?
Only lets in certain molecules and restricts the movements of other molecules
What affects a chemicals ability to move across the cell membrane?*
It's water solubility
What population has the least amount of water present in the body?
Obese people, about 45%
When are polar bonds formed?
When atoms at each end of the bond have an opposite charge
When are non-polar bonds formed?
