Intro To Physiology - Membrane Physiology Flashcards
The amount of intracellular fluid in the body is?
2/3 (50-70%)
It is called the Internal Environment of the body; why is it called such a name?
Extracellular fluid; it contains ions and nutrients needed for survival, as such, all cells live in the same environment.
What does Extracellular Fluid (ECF) contain?
Sodium (Na+: most abundant cation), Chloride (Cl-: most abundant anion), Calcium+ (Ca2+) Bicarbonate Ions.
Oxygen (O2), Carbon Dioxide (CO2), Glucose, Fatty Acids and Amino Acids, and waste products.
What does Intracellular Fluid (ICF) contain?
Potassium (K+), Magnesium (Mg+), Phosphate Ions (Po^-3 4), Organic Anion (the most abundant anion)
Maintenance and stability/constant conditions in the internal environment/organs to help perform functions
Homeostasis
It is often considered to be a state of disrupted homeostasis.
Disease
If a factor becomes excessive or deficient, a control system initiates _________.
Most control systems of the body act on it.
Negative Feedback
Initiating a stimulus causing more of the same reaction is?
Positive Feedback
The basic living unit of the body
Cells
About ____ of the adult human body is fluid, _____ intracellular fluid, ______ extracellular fluid
60%, 40%, 20%
The Basic Characteristics of Cells (4):
Oxygen for energy release
General Mechanism for changing is converting energy into nutrients
All cells deliver end products
Almost all cells have the ability to reproduce additional cells of their own kind
It is in constant motion throughout the body
Extracellular Fluid
ECF consists of ____ plasma and _____ interstitial fluid.
5%, 15%
The water element of blood
Plasma
It is seen between the spaces of the tissue
Interstitial Fluid
It is where most of the fluid in the body is contained
Intracellular Fluid
How does blood get transported to the system by the ECF?
Two Stages:
1.) Movement of blood through the body in the blood vessels
2.) Movement of fluid between the blood capillaries and intracellular spaces between the tissue cells
Origin of Nutrients in the ECF: Respiratory System
Blood picks up oxygen in the alveoli, thus acquiring oxygen needed by the cells.
Origin of Nutrients in the ECF: Gastrointestinal Tract (GI tract)
Ingest from food; for chemical nutrients
Origin of Nutrients in the ECF: Liver and Other Organs That Perform Primarily Metabolic Functions
Liver changes the chemical compositions of substances to usable forms, other tissues of the body—fat cells, gastrointenstinal mucosa, kidneys and endocrine glands—help modify/stored until they are needed
Origin of Nutrients in the ECF: Musculoskeletal System
Movement for survival and protection
Removal of Metabolic End Products: Lungs
CO2 is released from the blood into the lung aveoli; removal of Carbon Dioxide (CO2)
Removal of Metabolic End Products: Kidneys
Controls extraction of salt, water and waste products
Removal of Metabolic End Products: Gastrointestinal Tract
Undigested material that enters here, some waste products of metabolism are eliminated in the feces.
Removal of Metabolic End Products: Liver
Detoxification of drugs and chemicals ingested; secretes waste into bile to be eliminated in the feces
Regulation of Body Functions: Nervous System, what does it do?
Regulates muscular and secretory activities; Autonomic Nervous System (ANS) controls many of the internal organs
Nervous System has three (3) portions:
Sensory Input, CNS, Motor Output
Regulation of Body Functions: Hormone/Endrocine System
Hormones are transported in the ECF to help cellular function
Major Endocrine Glands in the Body + Uses (4):
1.) Thyroid Horomone - increases chemical reactions -> helps set tempo of bodily activity
2.) Insulin - sugar; controls glucose metabolism
3.) Adrenocortical Hormones - controls sodium (Na+) and protein metabolism
4.) Parathyroid Hormone - controls bone calcium and phosphate
Protection of the body: Immune System
Mechanism: distinguishes its own cell from harmful ones.
Destroys invaders by: phagocytosis/sensitized lymphocytes (eg. Antibodies)
Protection of the body: Integumentary System
Skin, hair, nails, glands, etc. cover and protect the deeper tissues and organs of the body.
Provide a boundary between the body’s internal environment and the outside.
Helps in temperature regulation.
Two major parts of a cell:
Nucleus and Cytoplasm
The nucleus is seperared from the cytoplasm by a ______
Nuclear Membrane
Cytoplasm is seperated from the surrounding fluids by a _____
Cell Membrane/Plasma Membrane
Except for fat cells, cells are mostly comprised mainly of _____ in a concentration of 70-85%
Water
Provide inorganic chemicals for cellular reactions, necessary for the operation of some cellular control mechanisms
Ions
Most abundant in most cells are proteins, constitue 10-20% of the cell mass
Proteins
Present in the cell mainly in the form of long filaments that are ploymerd of many indiviual protein molecules
Structural Protein
Composed of combinations of a few molecules in tubular-globular from, mainly enzymes which are mobile in the cell fluid
Functional Proteins
Are several types of substances that are grouped together -> common property of being soluble in fat solvent
Lipids
Often account for as much as 95% of the fat cell mass; represents the body’s main storehouse of energy-giving nutrients -> provide energy
Triglycerides/Neutral Fats
Plays a major roll in cell nutrition; amount usually averages between 1-3%, maybe 6% (in liver cells)
Carbohydrates
Carbohydrates is also stored here; an insoluble polymer of glucose that can be depolymerized and used to supply the cell energy’s needs
Glycogen
Have a hydrophilic head and a hydrophobic tail; most abundant in cell membrane lipids
Phospholipids
Present in small amounts in the cell membranes, especially in nerve cells
Protection from harmful environmental factors, signal transmission, adhesion sites.
Sphingolipids
Are also lipids; are dissolved in the bilayer of the membrane, mainly help determine the degree of permeability (bilayer to water)
Cholesterol
Jelly-like fluid portion; mainly dissolved proteins, electrolytes and glucose
Cytosol
Ribosomes have particles present; ribosomes are composed of a mixture of RNA, function to synthesize new protein molecules in the cell
Rough (Granular) Endoplasmic Reticulum
Part of the endoplasmic reticulum has no attached ribosomes
Smooth (Agranular) Endoplasmic Reticulum
A layer of thin, flat enclosed vesicles; prominent in secretory cells
Golgi Apparatus
It breaks off from the Golgi Apparatus then disperse throughout the cytoplasm; intracellular digestive system.
Lysosomes
Physically similar to lysosomes, formed by seld-replication; combines O2 eith H ions to form Hydrogen Peroxide
Peroxisomes
Powerhouse of the cell; forms CO2, H2O, and ATP
Mitochondria
Network of fibrillar proteins (e.g. Microfilaments, Intermediate filaments)
Cell Cytoskeleton
Control center of the cell, sends messages to the cell to grow, mature and replicate; contains a large quantities of DNA
Nucleus
Different Questions Under One Card:
1.) Also called Nuclear Envelope, seperates the two bilayer membranes
2.) It surrounds the Nuclear Envelope in several thousands of ______
3.) Formation of _____ happens in the nucleus; accumulation of large amounts of RNA
1.) Nuclear Membrane
2.) Nuclear Pores
3.) Nucleoli
Crawling-like movement of an entire cell; needs ATP (e.g. White Blood Cells, Fibroblasts, Germinal cells of the skin)
Ameboid Movement
Whip-like movement, occurs mainly in two places: Surfaces of the Respiratory Airways, Inside surfaces of the fallopian tubes
Motile cilia
Nonmotile; generally occur only as a single cilium on each cell, “sensory antennae” involved in chemical and mechanical sensation signalling; occurs in the kidney
Primary Cilia
Not miscible with either ECF or ICF
Lipid Bilayer
Passive transport of ions from an area of high concentration to low concentration.
Diffusion
1.1 Occurs through a membrane opening without any interaction from a carrier protein, mixed without any help
1.2 Requires a carrier protein
1.1 Simple Difussion
1.2 Facilitated Difussion
Facilitated Difussion is divided into two subtypes:
1.2.1 Use of carrier proteins, changes shape
1.2.2 Opening and closing of gate; ion/small molecules
1.2.1 Carrier Mediated
1.2.2 Channel Mediated
Opening and closing of gates are controlled in two (2) principal ways:
A.) Molecular confirmation responds to the electrical potential of the cell (Sodium, Potassium, Calcium)
B.) Binding of another molecule with the protein (Acetylcholine)
A.) Voltage Gating
B.) Chemical Gating
Passive movement of water; from high to low concentrated areas due to difference of water; achieve equilibrium
Osmosis
Pressure difference to stop osmosis
Osmotic Pressure
Movement of substances across the membrane in combination with a carrier protein; against an electrochemical gradient
Active Transport
Low to high concentrated areas; energy is directed from breakdown of ATP
3.1 Primary Active Transport
Co-transport, counter-transport
3.2 Secondary Active Transport
Transported by vesicles
Vesicular Transport
Under Vesicular Transport:
1.) Expulsion of cell content
2.) Ingestion of particles
1.) Exocytosis
2.) Endocytosis
1.) “Cell eating,” vesicles fuses with lysososomes
2.) “Cell drinking”
3.) Receptors outside the plasma membrane
1.) Phagocytosis
2.) Pinocytosis
3.) Receptor Mediated Endocytosis
Classification of Nerves Based on Fiber Types (6):
1.) Motor nerves (muscle spindles, skeletal muscles, golgi tendons)
2.) Sensory nerves (touch, proprioception)
3.) Motor innervation (supply): muscle spindle
4.) Sensory nerves for fast and acute pain/sensory for temperature
5.) Autonomic nerve glands and visceral organs (e.g. breathing)
6.) Chronic and slow pain
1.) A-Alpha - large and mylienated
2.) A-Beta - “
3.) A-Gamma - “
4.) A-Delta - small and mylienated
5.) B- “
6.) C- small and unmylienated
Rapid changes in the membrane potential that spread rapidly along the nerve fiber membrane
Action Potentials
All or Nothing Principle:
1.) Amount usually required to cause an explosive development of action potential
2.) Is the firing level/threshold value
3.) Resting memebrane value is?
1.) 15-35mV
2.) -55mV
3.) -70mV
It moves Action Potential backwards, prevents action potential from happening too closely; highest point of positivity, Sodium gate closed
Absolute Refractory Period
Caused when sodium gated voltage opens -> slow opening of potassium gated channels -> charge of cell becomes positive
Depolarization
2 causes:
Rapid closure of sodium-gated channels -> opening of potassium gates= Potassium Enflux -> Charge of cells become negative
Repolarization
Cause: slow closure of voltage gated K+ channel -> charge of cells becomes more negative
Hyperpolarization
1.) State where there is a positively charged outside and a negatively charged inside caused by the Na-K-ATPase Pump
2.) 1/3 or 2/3 of the repolarization stage; must be stronger than the original stimuli
1.) Resting Membrane Potential
2.) Relative Refractory Period
