Chapter 1/ Homeostasis Flashcards
Study of how living organisms function
(molecular to whole organ system)
Physiology
How parts of the body work together
Function and integration
Physiology ‘‘gone wrong’’
Pathophysiology
Body organization
Cellular
Tissues
Organs
Organs systems
Organism
Body Cells and Body Tissues
4 main types
Muscle
Nervous
Epithelial
Connective
3 types of muscle cells in the human body
Cardiac, Skeletal, Smooth
A-Control of Cardiac and smooth muscle
B- Control of skeletal
A-Involuntary
B-Voluntary
*Long Cylindrical striated cells with many nuclei
*Voluntary contraction
*Most are found attached to the skeleton
*Responsible for voluntary movement
Skeletal muscle
-Branching striated cells, one nucleus
-Involuntary contraction
-Found in wall of heart
-Pumps blood through the body
Cardiac muscle
-Cells tapered at each end, one nucleus
-Involuntary contraction
-Found in walls of hollow internal organs, such as the intestines, and tubes, such as blood vessels
-Contraction in the digestive system moves food along
-When arranged in a circle, controls the diameter of the tube
Smooth muscle
Cell of the nervous system that is specialized to initiate, integrate, and conduct electrical signals to other cells
Neurons
A collection of neurons forms nervous tissue
brain or spinal cord
Form a nerve
Axons from many neurons are packaged
Epithelial cells are characterized and named according to their unique shapes
cuboidal, columnar, squamous
Epithelial cells specialized for the
selective secretion
absorption of molecules
protection
Epithelium Layers
Simple- is one-cell thick
stratified- numerous layers
-Several layers of flattened cells
-Located on the surface of the skin, the lining of the mouth, esophagus, and vaginas
-Provides protection against abrasion, infection, and drying out
Stratified squamous
-One layer of flattened cells
-located in air sacs of the lungs, hearts, and blood vessels lining
-Allow exchange of nutrients, gases, and wastes
Simple Squamous
-Usually two layers of cube-shaped cells
-Located in ducts of mammary glands, sweat glands, and salivary glands
- found in protection
Stratified cuboidal
-One layer of cube-shaped cells
-Located in the lining of kidney tubules and glands
-Functions in absorption and secretion
Simple cuboidal
-One layer of tall, slender cells
-Located in the lining of the gut and respiratory tract
-Functions in absorption and secretion
Simple columnar
-Several layers of tall, slender cells
-Rare, located in urethra( tube through which urine leaves the body )
-Function in protection and secretion
Stratified columnar
cells that connect, anchor, and support the structure of the body
connective tissue
Types of connective tissues include
specialized cells separated by extracellular matrix
-Loose Connective
-Dense Connective
-Blood(liquid)
-Bone (solid)
-Cartilage (solid)
-Adipose
-Widely distributed; found under skin, around organs, between muscles
-Wraps and cushion organs
Areolar connective tissue
-Found in rings of respiratory air tubes, external ear, tip of nose
-Provides flexible support ; cushions
Cartilage
-Found under the skin, around kidneys, and heart
- Functions in energy storage and insulations; cushioning for organs
Adipose (fat) tissue
-Found in the skeleton
-Function in support, protection ( by enclosing organs), and movement
Bone
-Found in tendon and ligaments
-Forms strongs bands that attach bone to muscle or bone to bone
Dense connective tissue
-Found within blood vessels
-Transports nutrients, gases, hormones, wastes; fights infection
Blood
-The environment that surrounds cells
-Provides a scaffold for cellular attachment
-Transmits information in the form of chemical messages to the cells
Extracellular matrix
Viscous fluid (component that is part of consistency of extracellular matrix)
bound substance
Extracellular composed of
Proteins
Polysaccharides
Minerals
-Organs are composed of multiple of tissues types
-Organs system contains multiple organs that work together
-Protects underlying tissues
-Provides skin sensation
-Helps regulate body temperature
-Synthesizes vitamin D
Integumentary system
-Attachment for muscles
-Protein organs
-Stored calcium and phosphorus
-Produced blood cells
Skeletal system
-Moves body and maintains posture
-Internal transports of fluids
-Generation of heat
Muscular system
Regulates and integrates body function via neurons
Nervous system
Regulates and integrates body function via hormones
Endocrine system
-Transports nutrients, respiratory gases, wastes and heat
-Transports immune cells and antibodies
-Transports hormones
-Regulates pH
Cardiovascular system
-Returns tissue fluids to bloodstream
-Protects against infection and disease
Lymphatic system
-Exchanges respiratory gases with the environment
Respiratory system
-Physical and chemical breakdown of food
-Absorbs, processes stores food
Digestive system
Watery solution of dissolved substances( oxygen, nutrients, etc) present in the body
body fluid
Intracellular fluid
contained within the cells
Extracellular fluid
in the blood/blood plasma and surrounding the cells/interstitial fluid
All living organisms maintain a relatively constant internal environment
(Physiological variables: blood pressure, body temperature, glucose, oxygen )
- is dynamic, not a static, process
- can undergo a drastic change over a 24 hr period
Homeostasis
Homeostatic Control ( set point=normal values)
-Negative feedback loops
-Resetting of set points
-Feedforward regulation
-Reflexes
a levels change over short periods of time but remain relatively constant over time
Dynamic Constancy
Negative feed back loops ( mechanism)
-Counteract changes to physiological variables
-Negative feedback stops once set point has been reached
-brought via reflex arcs
Resetting of set points
- '’Normal’’ values for variables can be reset to new value
Feedforward regulation
Changes to regulated variables are anticipated and prepared for before they occur
Reflexes
-a specific involuntary, unpremeditated, unlearned ‘‘built-in’’ response to a particular stimulus
-Pathways mediating a reflex is known as the reflex arc
Intracellular chemical messengers
-Hormones
-Neurotransmitters
-Paracrine substances
-Autocrine Substances
Hormones
-Secreted by endocrine
-Travel through blood target cells
Neurotransmitters
-Released by neurons onto other neurons, muscle cells, of glands
-signals involved in many reflexes
Variable feeder to be controlled in homeostasis
1-Receptors= Pancreas (detects imbalace)
2- Control center Pancreas, (the brain sends the information )
3= Pancreas ( secrete glucose )
Targets cells in close proximity to the cells that secreted it
Paracrine substances
Acts on same cell that secreted it
Autocrine substances
-Characteristics that favor survival in specific environments
-Inherited
Adaptation
Improved functioning of an already existing homeostatic system based on an environmental stress
Acclimatization
Body function are
rhythmical changes
-enable homeostatic mechanism to be activated at times change will likely occur
Circadian rhythm: a 24 hr cycle
-walking and sleeping
-body temperature
-Hormone concentration
Many homeostatic systems regulate the balance between addition and removal of a chemical substance from the body
Three states of total-body balance are possible
-Negative balance(loss>gain)
-positive balance ( gain> loss)
-stable balance (gain=loss)
