Physiology XA: flashcards

PHYL 1011 Exam 1

Physiology

THe study of normal functioning of a living organism and its component parts, including all of its chemcial and physical processes

Levels of Organization

atoms-molecules-cells-tissues-organs-systems-organisms-populations-ecosystems-biosphere

Circulatory (cardiovascular)

transport of materials between all cells of th body

Digestive System

Conversion of food into particles that can be transported into the body and the elimination of some waste

Endocrine

Coordination of body function through synthesis and release of regulatory molecules

Immune System

Defense against foreign invaders

Integumentary

Protection from external enviornment

Musculoskeletal System

Support and movement

Nervous System

Coordination of body function through electrical signals and release of regulatory molecules

Reproductive System

Perpetuation(continuing) of the species

Respiratory System

Exchange of oxygen and carbon dioxide between the internal and external enviornments

Urinary System

Maintanence of water and solutes in the internal enviornment and waste removal

External enviornment

The enviornment the organism lives in (the atmosphere)

External enviornment examples

digestive tract, respiratory tract excluding the lungs, ureters, bladder, fallopian tubes

Internal Enviornment

The enviornment the cell lives in divided into the extracellular and the intracellular fluid

Internal Enviornment examples

lungs, kidneys, ovaries, skin, blood in the blood vessels

Extracellular fluid

fluid outside our cells

Intracellular fluid

Fluid inside our cells

Homeostasis

The ability of the human to monitor its internal enviornment and to take actions to correct or minimize disruptions that threaten its normal function

Homeostasis Examples

body temperature, blood pressure, heart rate, O2 in blood

Negative Feedback

Feedback are designed to keep the body in homeostasis

Negative Feedback example

thermoregulation, and blood sugar regulation

Positive Feedback

Positive feedback loops temporarily sends the body out of homeostasis and requires outside intervention to shut off the positive feedback loop.

Positive feedback examples

Contractions in childbirth

Local Control

Homeostatic control that takes place within a tissue

Reflex Control

Homostatic control that requires long distance signalling and involves many different organs

Plasma membrane is made of what

A phospholipid bi layer and proteins

Plasma Membrane functions

barrier between ICF and ECF, regulation of exchange between ICF and ECF via proteins, communication between ICF and ECF via proteins and structural support with proteins and carbohydrates.

Fluid Mosaic Model

Nucleus

It boundary, or nuclear envelope is a two membrane structure that seperates the nucleus from the cytoplasmic compartment Communication goes through the nuclear pores

Cytoplasm

Consist of a fluid portion called the cytosol, insoluble particles called inclusions, insoluble particles called inclusions and membrane bound strucutres collectively known as organelles

Cytosol

AKA intracellular fluid. A semi gelatinous fluid seperated from the extracellular fluid by the cell membrane.

Organelles

Membrane bound compartments that play specific roles in the overall function of the cell.

Mitochondria

Plays an important role in ATP production. Mitochondria are the site of most ATP synthesis in the cell. Spherical with a double wall that create two seperate compartments.

Rough ER

The main site of protein synthesis. Granular appearance due to the rows of ribosomes.

Smooth ER

synthesizes lipids and stores calcium ions. lacks ribosomes and appears as smooth membrane tubes

Golgi Apparatus

Consist of a series of hollow curved sacs called cisternae stacked on top of one another and surrounded by vesicles. Participates in protein modification and packaging.

Lysosomes

Act as the digestive system of the cell

Peroxisomes

Storage vesicles that are smaller than lysosomes.

Gap Junctions

Allow direct and rapid cell to cell communication between cytoplasm of neighboring cells

Tight Junctions

Restrict movement of material between the cells they link

Desosomes

Attach neighboring cells together and holds cells in place within tissue

ECF

1/3 of the total body water volume and consist of Interstitial fluid and blood plasma

Interstitial Fluid

Lies between the circulatory system and the cells

Blood plasma

Liquid matrix of blood

Osmotic equilibrium

Water is able to move freely between the ICF and the ECF therfore water distributes itself until the water concentration is equal

Chemical disequilibrium

The nature of the soultes is strikingly different between the ICF and ECF

Osmosis

Passive movement of water across a membrane in response to a solute concentration gradient

Osmotic Pressure

The pressure that the piston must exert to stop the movement of water when the osmotic pressure is high then the water movement is quicker

Osmolarity:

Calculates the number of particles in a solution

Hyperosmotic

greater osmolarity than

Isosmotic

same osmolarity than

hyposmotic

lower osmolarity than

Tonicty

describes the volume change of a cell considering only the non penetrating solutes

hypertonic

more tonic than

isotonic

same tonicty as

hypotonic

less tonic than

hypotonic cell

water will move into the cell

hypertonic cell

water will move out of the cell

osmosis movement

Water moves from areas of low concentration of solute to areas of high concentration of solute

Diffusion

Passive movement of solutes from an area of high concentration to an area of low concentration

Energy for diffusion

inherent kinetic energy from movement and potential energy from concentration gradient

Factors that determine rate of diffusion

concentration gradient (higher gradient higher rate), molecule size (bigger molecule, slower rate), and temperature (higher temp faster rate)

Membrane permeability

the ability of a membrane to let molecules pass through

Membrane permeability factors

lipid solubility (high lipid solubility high rate), size of molecule (big low rate), exact composition of the lipids within the membranes

How do liphophobic solutes move through the plasma membrane

They use proteins inserted in the plasma membrane called protein mediated transport

Two different types of proteins

Channel and Carrier Proteins

Create a water filled pore, direct link between ECF and ICF, no confirmation change, fast and used for small molecules

Channel Proteins

Confirmation change

change in protein shape

Require confirmation change to transport molecules and can carry one or molecules at once

Carrier proteins

Uniport

Move one specific molecule GLUT transporters

Symport

Moves 2 or more specific molecules in the same direction SGLT transporter

Antiport

Moves 2 or more specific molecules in the opposite direction Na+ ATPase

Transportation that uses protein carriers

Facilitated Diffusion

Facilitated Diffusion

Movement of molecules across cell membranes in repsonse to a concentration gradient with the aid of a membrane protein, Passive transport and goes from high to low concentration

Active Transport

requires input of ATP and transports solutes, ,low to high concentration and goes away from equilibrium

Carrier proteins

Bind to their substrate require conformation change, it is slower and used for larger molecules.

Protein carrier role in primary active transport

acts as an enzyme to break down ATP

Na+ K+ ATPase pump

What type of active transport is Na+ K+ ATPase

primary active transport

Steps of Na+/K+ ATPase

1. 3Na+ from ICF bind to affinity sites

2. ATPase is phosphorylated with P1 from ATP

3. Na+binding sites lose their affinity and release 3Na+ into ECF

4. 2K+ from ECF bind to high affinity sites

5. K+ binding sites lose their affinity for K+ and release 2K+ into ICF.

what type of active transport is the SGLT

secondary active transport

Steps for SGLT

1. Na+ binds to carrier

2. Na+ bidnign creates a high affinity site for glucose

3. Glucose binding changes carrier confirmation so that binding sites face the ICF

4. Na+ is released into cytosol, where Na+ is low. Release changes glucose bidning site to low affinity and glucose is released.

Specificity

Transporters can only move one specific molecule

Competition

When transporters can move more than one substrate, these molecules compete with one another

Saturation

ALl transporters work at their maximal capacity, transport rate can no longer increase

Endocytosis

Moves large molecules into the cell

Exocytosis

Moves large molecules out of the cell

Electrical Disequilibrium

Body is electrically neutral which means that there are an equal amount of cations and anions but they are unevenly distributed between the ICF and ECF

Resting membrane potential

-70mV

Electrochemical Equilibrium

The movement caused by concetration gradient is matched exactly by the movement caused by the electrical gradient

Equilibrium potential of K+

-90mV

Equilibrium Potential of Na+

60mV

WHat ion pulls harder on membrane potential

K+

WHat ion is more permeable to the cell

The cell membrane is more permeable to K+ than Na+

How is cell membrane potential is determined

concentration of K+ and Na+ in the ICF and ECF, the cell membrane permeability to K+ and Na+

Ways to change membrane potential andn why?

adding more channels which makes ions more permeable therfore causing more movement

hyperpolarization

dropping below -70mV

depolarization

moving above -70mV

repolarization

dropping back to -70mV