Ch 1 (Midterm 1) Flashcards
What are the four major types of tissues?
epithelial, muscular, neural, and connective tissues
What are the general functions of epithelial tissue?
selective secretion and absorption of ions and organic molecules and for protection
Where are epithelial tissues located?
surfaces that cover the body or organs, line inner surfaces of the tubular and hollow structures within the body
What are the general functions of muscular tissue?
generate mechanical force
Where are muscular tissue located?
skeletal=bones/skin | cardiac and smooth=heart and tubal structures like digestive tract and blood vessels
What are the general functions of neural tissue?
to initiate, integrate, and conduct electrical signals to other cells and provide a means of controlling the activities of other cells
Where are neural tissue located?
found in the nervous system
What are the general functions of connective tissue?
connect, anchor, and support the structures of the body and form extracellular matrix
Where are connective tissues located?
throughout the body depending on the kind of connective tissue
What is loose connective tissue?
connective tissues found in loose meshwork of cells and fiber underlying epithelial tissue
What is dense connective tissue?
tough rigid tissue making up tendons and ligaments
What is the extracellular matrix?
the environment that surrounds the cells in the body including the extracellular fluid
Other than loose and dense connective tissue, what other ones are there?
bone, cartilage, adipose, and blood
Functions of the extracellular matrix?
provides a scaffold for cellular attachments and transmits chemical messengers (info) to cells to regulate them
What does the extracellular fluid of the matrix composed of?
proteins, carbohydrates, elastin and collagen fibers
What ions and relative amounts of it are in the extracellular fluid?
100+ of Na & Cl || 5> of Ca and K
What ions and relative amounts of it are in the intracellular fluid?
100+ K || 10< Na/Cl || 1> Ca
What is plasma?
extracellular fluid that is the fluid portion of the blood
What is interstitial fluid?
fluid that makes up most of the extracellular fluid
What is intracellular fluid?
fluid within all cells in the body, makes up most of the fluid in the body
What is the intracellular fluid composed of?
proteins that are important for regulating cellular events like growth and metabolism
What is homeostasis?
the maintenance of the internal environment
How is homeostasis maintained?
sensors detect changes from set point > system processes/integrates sensory input > send out appropriate signals > signals trigger effector systems to go back to set point
Is homeostasis a simple process?
it is a dynamic process
How do we measure changes (sensory input) and correct for them in homeostasis?
integrating center will receive those messages and send output signals to correct for them
What is homeostatic controls system
mechanisms that mediate responses to change the internal environment to maintain homeostasis; includes positive and negative feedback
What is an integrating center?
receives sensory input and initiates response to maintain homeoestasis
What is positive feedback?
amplification of an effect by its own influence to reinforce its process
What is negative feedback?
when the system’s response reverses a process
What is equilibrium in terms of homeostasis?
energy is not required to maintain the constancy, no change in a particular variable
What is a steady state in terms of homeostasis?
energy input is needed to maintain constancy to achieve no change in a particular variable
What is a set point in terms of homeostasis?
the steady state value maintained by the homeostatic control system
What is the integrator part of the integrating center?
the brain region that compares the actual value of a variable (ie: body temp) to its set point
What is a reflex arc?
neural/hormonal components in the pathway that mediate a reflex
What is efferent?
component of reflex arc that moves info from integrating center > effector
What is afferent?
component of reflex arc that moves info from receptor > integrating center
What links the efferent and afferent branches of the reflex arc?
integrating center (the brain)
What is simple diffusion?
movement of molecules from one location to another based on random thermal motion
What is facilitated diffusion?
uses a transporter channel to move larger molecules down its concentration gradient
What is primary active transport?
active transport (against concentration gradient) via ATPases, ex: Na/K ATPase
What is secondary active transport?
moving ion down its electrochemical gradient coupled with transporting a large molecule against its concentration gradient
What is the function of simple diffusion?
help maintain homeostasis
What is the function of facilitated diffusion?
to move larger molecules down its concentration gradient across a plasma membrane
What is the function of primary active diffusion?
(Na/K ATPase) establish/maintain extracellular/intracellular concentrations of Na (extracellular) and K (intracellular)
What is the function of secondary active diffusion?
to move a large molecule (ie: proteins) against its concentration gradient)
What are the three ion gated channels?
ligand, voltage, and leak
Where are ligand-ion channels located?
dendrites and cell body of neurons
Where are voltage-ion channels located?
axon and synapse
Where are leak channels located?
dendrites, cell body, and axon
What is the function of ligand-ion gated channels?
responsible for synaptic potentials, incoming messages to the neuron
How do ion channels discriminate between ions?
the charge and size of ion and how much water it attracts
What is the function of voltage-ion gated channels?
directionally propagate electrical signals
What is the function of leak-ion channels?
responsible for resting membrane potential
