Introduction (1) Flashcards
Exam 1
Anatomy Definition
- structure
- complex interconnectedness of structures
Physiology Definition
-function (spectrum)
Comparative Physiology Definition
experimentation on humans not always practical, that’s why traditionally we have mammals
What is the goal of comparative physiology?
- to understand the function and integration
- understand organizational levels
Structure determines function and ____ informs ____
- function
- structure
What is the collection of qualities that distinguish from nonliving things?
Life
What are the characteristics of life?
- Cells
- Reproduction
- Growth
- Homeostasis
- Adaptability/Excitability
- Evolution
What are cells?
One or more -> are building blocks
What is the function of reproduction?
to make copies
What is growth
metabolic changes (metabolism) -causes development
What is the function of homeostasis?
maintain or relatively stable internal environment
What is evolution?
a change over time (often due to excitability)
What are the levels of organization?
- Atom
- Molecule
- Macromolecule
- Organelle
- Cell
- Tissue
- Organ
- Organ System
- Organism
What levels of organization make up chemicals?
- atoms
- molecules
- macromolecules
What makes up cells?
organelles
What makes up tissues?
similar cells/similar functions
What makes up organs?
two or more tissues types that work together
What makes up organ systems?
organs
How cells in cell differentiation classified?
- Muscular
- Nervous
- Connective
- Epithelial
What are multicellular structures made of?
Tissues- single cell type (aggregate)
What are tissues?
- similar cells and cell products
- related embryonically
- work in concert
What do major tissues types differ in?
- cell structure (type) and function
- Matrix (extracellular material)
- Cell:Matrix (cell to matrix ratio)
What is a matrix and what is is made of?
- nonliving matter secreted by tissues cells
- -Fibrous proteins
- -clear gel (ground substance, ECF)
Histology Definition
study of tissues
-organization within organs
Organ systems are __?
a collection of organs that work to carry out a specific function
What is body fluid?
a watery solution of dissolved substances (oxygen, nutrients, and wastes) present in the body
What are the two main types of body fluid and where are they found?
- Intracellular fluid- fluid within cells (~67% of all fluid)
- Extracellular fluid- fluid in blood and between cells (~33%) (20-25 plasma and 75-80 around the cells)
Extracellular and intracellular fluid composition is very different and ___ __ ____?
vital to survival
Gradient Definition
difference in chemical concentration, charge, temperature, or pressure between two points
Matter and energy flow __ the gradient
down
Movement in the opposite direction is __ or ___ the gradient
- up
- against
What flows down?
- chemicals
- charged particles
- heat
What happens in homeostasis?
Physiological variables (blood pressure, body temperature, and blood gases) are maintained within a predictable range
(can change dramatically over a 24-hour period but the body is still in overall balance)
Homeostasis Definition
physiological variables in a state of dynamic consistency (equilibrium)
(change is not STATIC, internal stability)
What happens in homeostatic control systems?
activity must be regulated/ integrated
Steady State Definition
a system in which a particular variable is not changing
What is Caveat?
energy must be added continuously to maintain a stable homeostatic condition (set point)
Set Point Definition
average value of a given variable
could change: example- marathon runners
When talking about a steady state, any regulated variable will…
Have a narrow range of normal values depending on the external environment conditions
Feedback System (Loops) Definition
fundamental mechanisms to control physiological processes
What are the two types of Feedback Systems (Loops) and what do the do?
- Positive- enhances production of a product (accelerates a process)
- Negative- bring variable back to original state (negates a change)
Draw a feedback loop:
Physiological variable —stimulus—> Receptor ——> Control Center ——> Effector Organ —Response—>
(Back to beginning)
What does a Response do in a feedback loop?
detects a change
What does the Control Center do in a feedback loop?
Activate the effector organ
What does an Effector Organ do in a feedback loop?
Produces a response
What type of cycle is a positive feedback loop?
A self- amplifying cycle
- -greater change in the same direction
- -feedback loop is repeated and produces more change
True or False:
A positive feedback loop produces rapid changes?
True
What are three examples of positive feedback loops?
- childbirth
- blood clots
- fever
Steps in the positive feedback loop of childbirth:
- Head of fetus pushes against cervix
- Nerve signals from cervix transmitted to brain
- Brain stimulates pituitary gland to secrete oxytocin
- Oxytocin carried in bloodstream to fetus
- Oxytocin stimulates uterine contractors and pushes fetus toward cervix
What type of process is a negative feedback loop?
Continuous, ongoing processes
–effectors are generally increased/decreased in activity
How does a negative feedback loop work?
The body senses a change and activates mechanisms to negate (reverse) it
–Maintain values around a set point
Explain the parts of a Negative Feedback Reflex Arc
- Stimulus: detectable change (internal/external)
- Receptor: detects change
- Signal travels between the receptor and integrating center along the afferent pathway
- integrating (control) center: decision to respond
- Information going from the integrating center to the effector travels along the efferent pathway
- effector: sends response
Intrinsic Regulation Definition
within the organ being regulated
Extrinsic Regulation Definition
nervous/endocrine
- nervous system: regulates secretion of endocrine hormones
- hormones: regulate function of nervous system (find receptor and target cell
What is Negative Feedback Inhibition
- secretion of a hormone can be inhibited by its own effects (closed-loop system)
- hypothalamus doesn’t make decisions without input
