Lecture 1: Chapter 1: The Study of Body Function Flashcards
Physiology
the study of biological function; how the body works…
1) normal function of cells
2) mechanisms of action
3) cause-effect relationships
4) derived from science experiments
Pathophysiology
how disease and injury affects biological processes
Comparative Physiology
studies similarities and differences of animal organisms and aids development of drugs
Good physiological research requires:
1) quantifiable measurements
2) an experimental and control group
3) statistical analysis
4) review/publication in journal
Steps to Develop Pharmaceuticals
1) research and development
2) in vitro cell culture tests
3) animal tests (rodents) on genetically modifies rodents susceptible to studied disease - look for side effects
4) clinical trials with humans
Phases of Clinical Trials
Phase 1) testing on healthy human volunteers for side effects
Phase 2) test for effectiveness on people with the disease
Phase 3) increase sample size to include many age groups/ethnicities/diversity of ppl with >1 health condition (FDA can the approve)
Phase 4) trials to test other drug applications
Who demonstrated that the heart pumps through a closed vessel system?
William Harvey
Who observed that the internal body environment stays relatively constant?
Claude Bernard
Who coined the term “homeostasis”?
Walter Cannon
Homeostasis
the constancy of the internal environment and the main purpose of physiological mechanisms
How is homeostasis generally accomplished?
negative feedback loops
Three Components of Negative Feedback Loops
1) sensors
2) integrating centers
3) effectors
Sensors
detect change and send information to the integrating center
Integrating Centers
receive information of change from sensors and direct effectors appropriately
Effectors
receive information from the integrating center to enact change that counterbalances the environmental changes detected by the sensors
Antagonistic Effectors
opposing effectors that move conditions in opposite directions around the set point in order to maintain conditions in a normal range
Dynamic Constancy
process of maintaining body conditions within a certain normal range
Positive Feedback
when the end product of a reaction chain stimulates the process to occur again
Negative Feedback
when the end product of a reaction chain inhibits the process from occurring again
Can positive feedback work alone?
No, but it is apart of many negative feedback systems
Intrinsic Organ Regulation
cells within an organ sense a change and signal neighboring cells to respond appropriately
Extrinsic Organ Regulation
the brain or other organs regulate an organ using the endocrine or the peripheral and autonomic nervous systems
Neural Regulation
the nervous system “innervates” organs with nerve fibers
Endocrine Regulation
releases hormones into the blood which transports them to multiple target organs
System for Hormone Secretions
1) hormones are secreted in response to a certain stimuli; 2) secretion can be inhibited by its own effects; 3) neg fdbk usually involves an antagonist to ensure homeostasis
Cell
basic unit of structure and function of living things
Tissue
group of cells that perform a similar function
Organ
group of two or more tissues into structural and functional units
Organ System
group of organs that work together in coordination
Organism
systems working together in coordination
Four Types of Primary Tissues
1) muscle
2) nervous
3) epithelial
4) connective
What are muscle tissues specialized for?
contraction
Three Types of Muscle Tissue
1) skeletal muscle
2) cardiac muscle
3) smooth muscle
Features of Skeletal Muscle
1) voluntary; 2) associated with skeletal bones; 3) produce body movements; 4) long, cylindrical, multi nucleated cells (myofibers) with visual striations; 5) form parallel bundles; 6) produce graded response; 7) few aren’t associated with skeleton (tongue, esophagus, sphincters, diaphragm)
Which type of muscle cells are voluntary?
skeletal
Which type of muscle cells are associated with bones?
skeletal
Which types of muscle cells can be found in the diaphragm?
skeletal
Which type of muscle cells produce a graded response?
skeletal
Which type of muscle cells are long and multi nucleated?
skeletal
Which types of muscle cells are most responsible for body movements?
skeletal
Which type of muscle cells form parallel bundles?
skeletal and cardiac
Which type of muscle cells are long and cylindrical?
skeletal
Which type of muscle cells make up sphincters?
skeletal
Myofibers
long, cylindrical, multi-nucleated cells
Which type of muscle cells form striations?
skeletal and cardiac
Cardiac Muscle
muscle found only in the heart
Features of Cardiac Muscle
1) only in heart; 2) short, branched fibers; 3) fibers are interconnected physically and electrically; 4) involuntary; 5) striated; 6) posses intercalated discs that allow passage of sodium ions between cells; 7) form parallel bundles; 8) cannot produce graded response due to their connectedness
Which type of muscle cells are responsible for heart contractions?
cardiac
Which type of muscle cells are involuntary
cardiac and smooth
Which type of muscle cells have intercalated discs?
cardiac
Which type of muscle cells are physically and electrically connected?
cardiac
Which type of muscle cells cannot produce a graded response?
cardiac and smooth
Which type of muscle cell have short, branched fibers?
cardiac
Smooth Muscle
responsible for contraction in organ walls
Features of Smooth Muscle
1) found in walls of digestive, urinary, reproductive organs, blood vessels and bronchioles of lungs; 2) not striated; 3) involuntary; 4) found in bundles/layers that form different/opposing directions; 5) act in paristalsis
Peristalsis
coordinated, wave-like contraction of smooth muscle layers to move substances through organs
Which type of muscle tissue has one nucleus?
cardiac and smooth
Which type of muscle cells are found in hollow organ walls?
smooth
Which type of muscle cells are found in blood vessels?
smooth
Which type of muscle cells form opposing bundles?
smooth
Which type of muscle cells conduct peristalsis?
smooth
Where can you find nervous tissue?
in the brain, spinal cord and nerves
Types of Nervous Tissue
1) neurons
2) neuroglia
Neuron Parts
1) dendrites; 2) axon; 3) cell body (perikaryon)
Neuroglia
supporting cells that do not conduct nerve impulses but are essential for nerve function
Perikaryon
cell body of nerve cell (metabolic center of nerve cell)
Epithelial Tissue
1) forms membranes that cover body surfaces, line inside of hollow organs and glands; 2) membranes classified by their layer number; 3) impermeable to blood vessels, nourished by connective tissues; 4) always sit on a basement membrane; 5) continually renew by losing surface cells and replacing them with new cells
Epithelial Layer Types
1) simple epithelium; 2) stratified epithelium
Simple Epithelium
has one layer and is specialized to transport substances
Stratified Epithelium
composed of multiple layers and provides protection
Epithelial Shape Types
1) squamous; 2) cuboidal; 3) columnar
Squamous Cells
flattened epithelial cells
Cuboidal Cells
epithelial cells that are as tall as they are long
Columnar Cells
tall epithelial cells
How do you name epithelial tissues?
cell shape classification + layer type
Goblet Cells
modified columnar tissues that secrete mucus and have cilia with coordinated movement
Which epithelial type covers visceral organs?
simple squamous
Which epithelial type lines body cavities?
simple squamous
Which epithelial type covers capillary walls?
simple squamous
Which epithelial type covers pulmonary alveoli of lungs?
simple squamous
Which epithelial type covers ovaries?
simple cuboidal
Which epithelial type covers lining of kidney tubules?
simple cuboidal
Which epithelial type covers salivary ducts?
simple cuboidal
Which epithelial type covers pancreatic ducts?
simple cuboidal
Which epithelial type covers most of the digestive tract lining?
simple columnar
Which epithelial type covers the lining of uterine tubes?
simple ciliated columnar
Which epithelial type covers the lining of respiratory pathways?
pseudostratified ciliated columnar
Which epithelial type covers the epidermis of the skin?
stratified squamous (keratinized)
Which epithelial type covers the lining of oral and nasal cavities?
stratified squamous (nonkeratinized)
Which epithelial type covers the vagina and anal canal?
stratified squamous (nonkeratinized)
Which epithelial type covers large ducts of sweat glands?
stratified cuboidal
Which epithelial type covers large ducts of salivary glands?
stratified cuboidal
Which epithelial type covers large ducts of the pancreas?
stratified cuboidal
Which epithelial type covers the walls of ureters?
transitional
Which epithelial type covers the urinary bladder and part of the urethra?
transitional
Junctional Complexes
structures that hold stratified epithelial tissue together
Nonkeratinized Stratified Tissues
these membranes have living cells in all layers
Keratinized Stratified Tissues
have cells filled with keratin (water-resistent) and layers of dead cells on surface
Exocrine Glands
1) derived from epithelial tissue; 2) secretions transported by ducts; 3) sercretors may be tubes or acini groups; 4) ex. sweat glands, salivary glands. etc.
Eccrine
type of numerous sweat gland that secretes salty sweat and involved in thermoregulation
Apocrine
sweat glands located on axillary and pubic regions that produce protein rich sweat for bacteria to feed on
Connective Tissues
a matrix of protein fibers, extracellular material and specialized cells
Four Types of Connective Tissue
1) Connective Tissue Proper
2) Cartilage
3) Bone
4) Blood
Connective Tissue Proper
composed of protein fibers and a gel-like ground substance
Loose Connective Tissue Proper
collagen fibers scattered loosely with room for blood vessels and nerves (upper layer of skin)
Dense Regular Connective Tissue Proper
densely packed collagen fibers with little room for ground substance (tendons and ligaments)
Types of Connective Tissue Proper
1) Loose; 2) Dense Regular; 3) Dense Irregular; 4) Adipose
Dense Irregular Connective Tissue Proper
connective tissue is composed of densely packed collagen fibers in various arrangements to resist mechanical forces
Adipose Connective Tissue Proper
tissue stores of fat, cells called adipocytes
Cartilage Connective Tissue
1) composed of chondrocytes surrounded by a semi-solid ground substance; 2) template skeleton during embryonic bone development; 3) found in joints to provide a gliding surface for bones
Bone
made of osteoblasts, osteocytes and lacunae; tooth dentin similar and made by cells in the pulp
Osteoblasts
bone cells that trap mineral salts, forming concentric layers of calcified material around a canal filled with blood vessels and nerves
Osteocytes
cells that osteoblasts turn into when the calcified matrix is hardened, live in lacunae
Lacunae
spaces in the bone matrix where osteocytes are found
Skin Tissue Types
1) epidermis (keratinized stratified squamous - protects against water loss and abrasion); 2) dermis (dense irregular connective tissue containing exocrine glands, hair follicles, sense receptors, blood vessels) and 3) hypodermis (adipose tissue for padding and insulation)
What types of germ layers can tissues come from?
endoderm, mesoderm or ectoderm
Totipotent (Omnipotent)
zygotes; cells can become any type of tissue cell of give rise to whole organism; true stem cells
Pluripotent
embryonic stem cells: descendants of totipotent cells and can differentiate into nearly any type of tissue cells
Mulitipotent
adult stem cells: limited to a narrow range of tissues, retained to allow for cell replacement in some tissue types
Intracellular
area inside cells, contains 65% of total body water
Extracellular
area outside of cells, filled with water
