Unit 1 Flashcards
What is physiology?
Study of structure and function of a living organism and its component parts
What are the organizational levels of living organisms?
A. Chemical - atoms & molecules
B. Cellular - neurons, lymphocyte
C. Tissue - collection of cells (ex: connective)
D. Organ - structural unit made of tissues (ex: heart)
E. Organ system - integrated group of organs
F. Organism - individual form of life (Community, ecosystem, biosphere)
What are cells held together by?
anchoring junctions, gap junctions, tight junctions
What are the 4 tissue types in the human body?
Epithelial, connective, muscle, neural
What are the functions of the epithelial tissue?
- protect the internal environment of the individual
- regulate exchange of material between external environment and internal environment
What are the 5 types of epithelia and their functions?
- Exchange: rapid exchange of material
- Ciliated: line airways & female reproductive tract
- Secretory: synthesize and release products into the external environment/blood
- Transporting: selective transport of material
- Protective: found on surface on the body
What is the function of the connective tissue?
Provides structural support and barriers
What is distinctive about the connective tissue?
It contains a high amount of extracellular matrix
What are the 5 types of connective tissue and their functions?
- Loose - elastic tissue
- Dense - strength is the primary function
- Adipose - contains adipocytes (fat)
- Blood - watery matrix lacking insoluble protein fibers
- Supporting - dense substance
What is the functions of the muscle tissue?
Ability to produce force and movement
What are the 3 types of muscle tissue and their functions?
- Skeletal: responsible for gross body movement
- Smooth: Responsible for influencing movement of substances in/out of/within the body
- Cardiac: found only in the heart, contraction moves blood around the body
What is the function of the neural tissue?
Carry information from one part of the body to another
What are the 2 types of neural tissues and their functions?
- Neurons: carry information as electrical or chemical signals
- Glial cells: supporting cells for neurons
What is function and what is mechanism?
Function: the function of a system is the “why”
Mechanism: the process of a system is the “how”
How do physiologists study function and mechanism?
They study mechanism to understand function
What is homeostasis?
Maintenance of a stable internal environment
What is the result of homeostasis?
Oscillation around a set-point
How do set points change with time?
Acclimatization: Environmentally induced change in physiological function with no genetic change
Circadian rhythms: daily biological rhythms
What are the 4 basics mechanism of cell-to-cell communication?
- gap junction
- contact-dependent signals
- local communication
- long-distance communication
What are gap junctions?
- direct cell-to-cell communication via protein channels (connexons) between adjacent cells
- capable of opening and closing
- found on many cell types
What are contact-dependent signals?
Interaction between membrane molecules on 2 cells
found in immune cells
What is local communication?
Occurs via paracrine and autocrine signals
paracrine secreate on neighboring cells (histamine)
autocrine secrete on themselves
What is long-distance communication?
- responsibility of endocrine and nervous systems
nervous system uses electrical and chemical signals
endocrine system uses only chemical signals (hormones)
Why do some cells respond to a chemical signals and others do not?
- Target cells have various receptor proteins
2. Only respond to a chemical signal if they have the appropriate receptor
What are the 3 domains of receptors?
- Extracellular domain: involved in binding the ligand
- Intracellular domain: involved in actiating the cellular response
- Trans-membrane domain: hydrophobic
How is homeostasis maintained by local control?
Effects are exerted on neighbouring cells (paracrine)
How is homeostatis maintained by reflex control?
Reaction in one or more organs are controlled from elsewhere in the body (nervous and/or endocrine systems)
TRUE or FALSE.
Homeostatic systems maintain constancy NOT similaroty.
FALSE. it maintains SIMILARITY.
What are the 3 types pf control systems that regulate response loops?
- Negative feedback
- Positive feedback
- Feedforward control
What is negative feedback?
IT results in a change that opposes or removes the signal
Allows for homeostatic control
What is positive feedback?
Response sends a signal, reinforces stimulus, send variable further from set point
NOT homeostatic
needs an external factor to end it
What is feedforward control?
Anticipatory control: predicts that change is about to happen, starts the response loop, prevents change
