1 Introduction to Physiology Flashcards
study of the function of living systems.
Physiology
study of how cells work encompassing the study of events at the chemical, molecular, and genetic levels.
Cellular physiology
study of specific organs
Organ physiology
study of the function of a specific system such as the cardiovascular, respiratory, or reproductive systems.
systems physiology
Levels of Organization (6)
- Chemical level
- Cellular level
- Tissue level
- Organ level
- Organ system level
- Organismal level
*Levels of Organization
atoms are the smallest units of matter that combine to form molecules.
Chemical level
*Levels of Organization
cells are the smallest unit of life. They exhibit various sizes, shapes, and properties that enable them to carry out specialized functions.
Cellular level
*Levels of Organization
a tissue is a group of cells having a common structure and function.
Tissue level
*Levels of Organization
two or more tissues working for a given function form an organ.
Organ level
*Levels of Organization
Organs work together for a common function. For example, the alimentary canal, pancreas, gallbladder, and deliver work together to carry out the proper function of the digestive system.
Organ system level
*Levels of Organization
all of the organ systems work together to maintain homeostasis.
Organismal level
Milieu interieur, coined by 19th-century French physiologist ____
Clause Bernard,
refers to the relatively constant internal environment which is the extracellular fluid where cells live.
Milieu interieur
who is the 20th-century American physiologist that later coined the term homeostasis
Walter Cannon,
“unchanging” internal environment.
homeostasis
the term used when regulation occurs at either the cellular, tissue, organ or organ system level.
Ex: release of cholecystokinin when the presence of tryptophan is detected in the small intestine prompting the pancreas to release digestive enzymes.
Autoregulation
involves the coordinated action of nervous and endocrine systems.
Ex: release of norepinephrine, epinephrine, and corticosteroids from adrenal glands during prolonged stress prompting the increase in blood pressure and flow to the skeletal muscle.
Extrinsic regulation
responds to immediate, short-term needs.
Ex: reflex arc in which an animal withdraws its foot after stepping on a sharp object.
Nervous system
elicits responses that last hours or days.
Ex: release of insulin in response to a rise in blood glucose levels.
Endocrine system
The regulatory mechanisms involve a ?
receptor
control center
effector
a specialized cell or a protein cell component that senses a change in the environment called a stimulus.
receptor
In response to the stimulus, the receptor carries what signal to the control center.
afferent (away) signal
has a set point around which the variable is maintained.
control center
what signal is sent to the effector
efferent (toward) signal
induces a change in the controlled variable to bring it back to the set point.
effector
Which feedback systems are more common
Negative feedback systems
The control system initiates changes that counteract the stimulus which will either reduce or eliminate the stimulus, thus, reestablishing the variable near its set point to maintain homeostasis.
Negative feedback system
The animal elicits regulatory mechanisms that augment the effect of a stimulus.
Positive feedback system
