KNES 323 EVERYTHING

what is physiology?

the study of functions and mechanisms responsible for the control and regulation of living things

What is the difference between afference andefference!

Afference is to the brain, efferent is from

Where does the somatic NS go to?

Skeletal muscle

Where does the sympathetic NS go to?

Smooth muscle, cardiac muscle, glands

Where does the parasympathetic NS go to?

Smooth muscle, cardiac muscle glands

Where does the enteric NS go to?

Smooth muscle and glands of GI tract

What serves the integrative function of the NS?

Association or interneurons

Why is white matter in the middle of the brain?

We send impusles straight up through the center of the brain.

Why is gray matter in the center of the spinal cord?

Reflex arcs go inside so we want to protect it so we have white matter outside

What is the function of the thalamus?

Redirects messages

Where do we see summation of action potentials?

Axon hillock

What are our excitatory and inhibitory neurotransmitters?

Excitatory is glutamate, inhibitory is gaba or dopamine

What type of synapse occurs in the heart?

Electrical through gap junctions because desmosomes are packed together not allowing it

What are the characteristics of our voltage gated channels during the absolute refractory period.?

Voltage gated Na channel activations gates are open, Na channels are inactivating as K channels open

What are the characteristics of our voltage gated channels during the relative refractory period.?

K channels are open, na channels in resting stage

What is korotkoff sounds?

Describes sound associated with turbulent flow not laminar or non existent flow

What side of the heart pumps harder? Do the different sides pump different volumes of blood?

Left side because it pumps to body but both sides pump the same volume

What does the dicrotic wave represent?

Represents the closing of the aortic semilunar valves which fills blood into the coronary arteries

What is the TP. Interval?

Time between start of ventricular repolarization and next atrial depolarization

What is the function of the pericardial cavity?

Allows smoother movement, prevents friction, keeps things open

What is key about the location of the coronary arteries/

Prevents collapse, when valves open they block the arteries

Why do conducting and contractile cells have different action potentials?

Conducting cells don’t really have refractory period but contractile do to allow filling and rest of ventricle

What are the different types of white blood cells?

Neutrophils, lymphocytes, monocytes, eosinophils, basophils

What does blood transfusion involve?

Certain parts of blood, RBC, Platelets, plasma, rarely whole blood (rbc, wbc, plasma, platelets)

What is the most and least common WBC?

Most common is neutrophils, least is basophils

What is the general concentration of formed elements?

RBC> platelets > WBC

What happens with very low hematocrit?

low hematocrit means low viscosity and easy flow but no metabolism

What happens with very high hematocrit?

High viscosity, hard to pump blood and die young

What is seen in each diagram?

Normal (hematocrit 45%), anemia (hematocrit 30%), polycythemia (hematocrit 70%), dehydration (hematocrit 70%)

what is metabolism?

set of life-sustaining chemical processes that enable organisms to transform chemical energy stored in molecules into energy that can be used for cellular processes

what is responsiveness?

react and change to environment

what is growth?

increase in the number and size of cells in an organism

what is differentiation?

less specialized cell matures to a more distinct form and function

what is the chemical level of the body?

atoms (smallest units of matter that participate in chemical reactions, molecules (two or more atoms joined together)

what are cells?

basic structural and functional units of an organism

what are tissues?

groups of similarly specialized cells and the substances surrounding them that usually arise from a common ancestors and perform certain special functions

what are organs?

structures of definite form that are composed of two or more different tissues and have specific functions

what is the human organism?

collection of structurally and functionally integrated systems

what is homeostasis?

condition of equilibrium, or balance, in the body’s internal environment maintained by the body’s regulatory processes

what must a control system be able to do in order to maintain homeostasis?

detect deviations from normal in the internal environment that need to be held within narrow limits even through changes, integrate this info with other relevant info, make appropriate adjustments to restore a factor to its desired value

what is a set point of an individual’s body systems?

the normal range for a given system that is monitored by the control centre for that system

what is the control systems for body temp?

hypothalamus

what are circadian rhythms?

endogenous autonomous oscillators of physiological activities that result in cycles allowing organisms to adapt to a fluctuating environment

what is the circadian clock system?

major regulatory factor for almost all physiological activities and its disorder can have severe consequences on human health

what are intrinsic controls?

local controls that are inherent in an organ

what are extrinsic controls?

regulatory mechanisms initiated outside an organ, accomplished by nervous and endocrine systems

what are feedback loops?

responses made after a change

what are feedforward loops?

responses made in anticipation of a change, aim to anticipate changes before they occur

what are negative feedback loops?

primary type of homeostatic control, opposes initial change

what are the components of a negative feedback loop?

sensor (monitors magnitude of a controlled variable), control centre (compares sensors input with a set point), effector (makes a response to produce a desired effect)

what is the main goal of the negative feedback loop?

keeping internal environment stable, only controlling within the body

what does the negative feedback loop control?

body temp, nutrients/wastes, O2/Co2 levels, pH, water/electrolytes, blood volume/pressure

what is an example of a negative feedback loop?

blood pressure control

what is a positive feedback loop?

amplifies an initial change, doesn’t truly contribute to homeostasis, response reinforces stimulus causing effect

what is an example of a positive feedback loop?

contractions during labour

what is disorder in homeostatic imbalances?

general term for any derangement of abnormality of function

what is meant by disease in homeostatic imbalances?

more specific term of an illness characterized by a recognizable set of signs and symptoms

what is aging in homeostasis?

characterized by a progressive decline in the body’s ability to restore homeostasis

what is an example of feedforward mechanisms in the mouth?

saliva production before eating, prepare for the breakdown of carbohydrates

what is an example of feedforward mechanisms in digestion (past the mouth)?

mechanism increases secretion of insulin to promote cellular uptake and storage of nutrients

what is an example of feedforward mechanisms in exercise?

central command primes body for changes about to take place during the exertion (oxygen extraction rates, cardiac output rates, and oxygen demand increases)

what is an example that demonstrates this circadian rhythm discussed?

cortisol increasing during the day and alternating with melatonin increasing at night demonstrates everything is intertwined to create these cycles

what are the basic components of a feedback loop?

stimulus, controlled condition, receptors, control center, effectors, response

what is the purpose of receptors in a basic feedback loop?

send nerve impulses or chemical signals to a control center

what is the purpose of a control center?

receives input and provides nerve impulses or chemical signals to an effector

where are the most baroreceptors found?

arch of the aorta, also found in the internal carotid

what as an example outside of childbirth for positive feedback loops?

hemostasis, blood clotting

what equation can be used to represent energy balance?

energy intake = internal heat production + internal work + external work + energy storage

what is the law of thermodynamics? What does it tell us?

energy cannot be created or destroyed, thus there is a balance between energy input and output

what is meant by energy input?

energy in ingested food, cells capture portion in high energy bonds of ATP, allows us to do energy output

what does energy output consist of?

external work and energy from nutrients not used to perform work

what is meant by external work in energy output?

energy expenditure when skeletal. muscles are contracted to move external objects or move the body in relation to the environment

about how much of energy is used for biological work and of this energy what occurs to the excess?

25% of chemical energy is used for biological work, the rest is converted to heat/thermal energy (mostly used for body temp regulation)

what is meant by energy storage?

internal work, all other forms of biological energy expenditure that do not accomplish mechanical work outside the body

is all skeletal muscle used for external work outside the body?

no some can be used for things like postural maintenance contractions and shivering

what does internal work include?

all energy expending activities that occur throughout life, skeletal muscle activity outside of that used for external work

what are the three possible states of energy balance?

neutral, positive, or negative balance

what is meant by a neutral energy balance?

energy input = energy output, body weight is constant

what is meant by a positive energy balance?

energy input is greater than energy output, energy not used is stored mostly as adipose, body weight increases

what is meant by a negative energy balance?

energy input is less than energy output, stored energy is used to supply energy needs, body weight decreases

what is meant by metabolic rate?

total amount of energy we need to expend (internal and external work) to perform a given task, energy expenditure/unit of time

what is meant by basal metabolic rate?

the minimal amount of internal energy expenditure that must be maintained for basic physiological functions

what is required to determine our BMR and under what conditions?

calorimetry, person is physical and mentally at rest, done in a comfortable room temperature , no food consumption within 12 hours

what factors influence our metabolic rate?

thyroid hormone level (primary determinant of BMR), sympathetic stimulation (epinephrine/norepinephrine), exercise, daily activities, age, sex/gender

what is the primary determinant of BMR?

thyroid hormone levels

explain how metabolism works with the energy we consume through food?

humans eat food to replenish energy, metabolism breaks down carbohydrates, lipids, proteins and nucleic acids to provide chemical energy for cellular processes

what occurs for every action that requires energy?

many chemical reactions take place to provide energy to our body systems including the muscles, heart, brain, nerves and lungs

what is meant by an anabolic reaction?

cellular processes that builds complex molecules

what is meant by catabolic reaction?

cellular process that breaks down complex molecules

what is meant by exothermic reaction?

reactions that releases energy

what is meant by endothermic reaction?

reaction that requires energy to proceed

what is a big part of our cellular metabolism?

all chemical reactions that take place inside our cells

overall what can potential energy be used for in metabolism and where is it found?

potential energy in chemical bonds can be used to perform work or for biological processes

explain the release of energy through metabolism and its purpose

many metabolic processes breakdown organic molecules to release energy for growth and survival

what is required to start a chemical reaction?

each chemical reaction has a certain amount of activation energy required to start it

what is the role of enzymes in activation energy?

can act as catalyst to reduce the amount of activation energy required and to increase reaction rate

what happens if an enzyme is not active in metabolism?

each enzyme can only control one type of chemical reaction so if it is not active the whole pathway stops working

what is meant by metabolic regulation?

cells use specific molecules to regulate enzymes to promote or inhibit certain chemical reactions

why is it necessary to inhibit reactions sometimes?

to reduce reaction rate

what is competitive inhibition?

inhibitor molecule is similar to substrate so it binds to the enzymes active site preventing the substrate from binding, the substrate and inhibitor compete to bind to the enzyme