Chapter 1 Flashcards
What is physiology?
study of how the body works to maintain life
What is pathophysiology?
study of how physiological processes are altered in disease or injury
What is the scientific method?
1) Observe something
2) Form a testable hypothesis with control and experimental groups
3) Conduct and analyze experiments
4) Draw conclusions about whether or not results support hypothesis
5) Develop a theory
What is homeostasis?
maintenance of the internal environment within a range of values
What kind of feedback loop is homeostasis?
negative feedback loop
What is a sensor?
detects deviation from set point
What is an integrating center?
determines response
What is an effector?
produces response
What is the sequence for a response loop?
- stimulus
- sensor
- afferent pathway
- integrating center
- efferent pathway
- effector
- response
What is negative feedback?
change from an ideal value is made smaller or resisted
What does negative feedback lead to?
healthy state and maintains homeostasis
What is positive feedback?
change from an ideal normal value is made greater
What does positive feedback lead to?
decompensated, disease state and away from homeostasis
When is positive feedback good?
- produces blood clots
- causes ovulation
- oxytocin secretion during labor
What is the response loop for blood glucose?
- eating
- increase in blood glucose
- pancreatic islets
- increase of insulin
- increase of cellular uptake of glucose
- decrease in blood glucose
What are the four types of primary tissues?
muscle
nervous
epithelial
connective
What are muscle tissue for? What are the 3 types?
contraction!
- skeletal
- cardiac
- smooth
What are the characteristics of skeletal muscle?
striated
- voluntary contraction
- each fiber forms by fusion of embryonic myoblasts (allows it to be large and multinucleated)
- individually controlled
- parallel with other fibers to form bundles
What are the characteristics of myocardial cells?
- short, striated, involuntary
- branched to form continuous fabric
- intercalated discs between cells that provide mechanical and electrical interconnections
- not individually controlled
What are the characteristics of smooth muscle?
not striated, involuntary
- found in many organs, tissues
- controlled by autonomic nervous system
What is in nervous tissue?
- neurons
- supporting or glial cells
What do neurons have? What is its function?
- cell body, dendrites, axon
- conducts electrical signals
What do cell bodies have? What is its function?
- nucleus
- metabolic center
What are dendrites and their function?
- branches from cell body
- receive inputs form other neurons
What are axons and their function?
single, long extension off cell body
- conducts nerve impulses to other cells
What is the function of supporting/glial cells?
provide physical and functional support for neurons
What are epithelial tissue? What are the 3 shapes?
- lines body surfaces
- consists of cells that form membranes and glands
- squamous: flat
- columnar: taller
- cuboidal: cube-shaped
How are epithelial tissues classified by layers? What are their functions?
Simple: thin and for transport
Stratified: lots of layers and for protection
What’s the difference between non-keratinized and keratinized cells?
non-keratinized: living cells
keratinized: outer layer of dead cells
- cells have water-resistant keratin
What are epithelial tissues joined and separated by? What’s the function?
junctional complexes
- increases strength and create barrier
- separated from underlying tissue by basement membrane
What are exocrine glands? What do they do?
glands that secrete things to the outside of the body
- derived from epithelial cells
- simple tubes or clusters called acini
What is connective tissue? What does it include?
lots of extracellular material in the space between cells
- connective tissue proper, cartilage, bone and blood
What does loose connective tissue have? Give an example.
collagen and tissue fluid
- dermis of skin
What does dense regular connective tissue have?
LOTS of fibers with collagen
- regularly arranged as tendons
- irregularly arranged as capsules or sheaths
What is adipose tissue?
fat
- fat synthesis, breakdown, storage
What is cartilage and its function?
chondrocytes and elastic extracellular material
- support, protection
- precursor for bone
- articular surfaces for joints
What is bone tissue?
concentric layers of calcified material
What are the 3 cell types of bone and their functions?
- osteoblasts: bone-forming
- osteocyte: inactive osteoblasts
- osteoclasts: bone-resorbing cell
What is the largest organ? What are the layers and their function?
skin
- epidermis: protection
- dermis: connective tissue, glands, blood vessels, nerves
- hypodermis: fat
What are stem cells?
highly specialized or differentiated
- can be used to repair or heal
Where do hair follicle stem cells form?
hair shaft, root sheath, sebaceous glands, epidermis
