Chapter 12 - Part 1 - The Cell Flashcards
Fundamental unit of life
The Cell
Three main elements of a cell
Cell Membrane
Cytoplasms
Nucleus
Semipermeability
The characteristic ability of a cell membrane to selectively permit material to pass through.
Nucleus
The structure that contains the genetic material including the cell’s DNA.
Cytoplasm
Thick viscous fluid that fills the cell and gives it shape
ATP - adenosine triphosphate
The compound that provides the cell with most of its energy
Cell Membrane
Aka Plasma Membrane
The outer covering of a cell
Organelles
Structures that perform specific functions within a cell
Structure Hierarchy of the Body
Cells > Tissues > Organs > Organ Systems > Organism
Tissue
A group of cells that perform a similar function
Epithelial Tissue
The protective tissue that lines internal and external body tissues.
Ex. Skin, Mucous Membranes
Muscle Tissue
Tissue that is capable of contraction when stimulated. 3 types:
Cardiac- capable of spontaneous or self- excited contraction.
Smooth- within intestines, surrounding blood cells. Under involuntary or unconscious control.
Skeletal- aka Striated. Allows skeletal movement. Mostly under voluntary control.
Connective Tissue
The most abundant body tissue; it provides support, connection, and insulation.
Ex. Bone, Cartilage, Fat, Blood
Nerve Tissue
Tissue that transmits electrical impulses throughout the body
Organ
A group of tissue functioning together.
Ex Heart, Liver, Brain, Ovary, Eye
Organ System
A group of organs that work together.
Organism
The sum of all the cells, tissues, organs and organ systems of a living being.
Ex. The human organism, a bacterial organism
TBW
Total Body Weight
The total amount of water in the body of a given time. Approximately 60% of the total body weight
ICF
Intracellular Fluid
The fluid inside the body cells; contained inside the intercellular compartment
75% of TBW
ECF
Extracellular Fluid
The fluid outside the body cells, comprised of intravascular fluid and interstitial fluid. The extracellular compartment contains it.
25% of TBW
Intravascular Fluid
The fluid within the circulatory system; blood plasma
Interstitial Fluid
The fluid in body tissues that is outside the cells and outside the vascular system
Solvent
A substance that dissolves other substances, forming a solution.
Water is the universal solvent. Water is crucial to virtually all of the body’s biochemical processes
Dehydration
Excessive loss of body fluid.
Some causes:
Vomiting, diarrhea, perspiration, peritonitis, malnutrition, burns, open wounds
Turgor
Normal tension in a cell; the resistance of the skin to deformation.
Overhydration
The presence or retention of an abnormally high amount of body fluid
Electrolyte
A substance that in water separates into electrically charged particles
Dissociate
Separate; break down. For example, sodium bicarbonate, when placed in water, dissociates into a sodium caution and a bicarbonate anion.
Ion
A charged particle; an atom or group of atoms whose electrical charge has changed from neutral to positive or negative by losing or gaining one or more electrons
Cation
An ion with a positive charge - so called because it will be attracted to a cathode, or negative pole
Anion
An ion with a negative charge - so called because it will be attracted to an anode, or positive pole
Buffer
A substance that tends to preserve or restore a normal acid-base balance by increasing or decreasing the concentration of hydrogen ions
Isotonic
Equal in concentration of solute molecules; solutions may be isotonic to each other
Hypertonic
Having a greater concentration of solute molecules; one solution may be hypertonic to another
Hypotonic
Having a lesser concentration of solute molecules; one solution may be hypotonic to another
Osmotic Gradient
The difference in concentration between solutions on opposite sides of a semipermeable membrane
Diffusion
The movement of molecules through a membrane from an area of greater concentration to an area of lesser concentration
Osmosis
The passage of a solvent, such as water, through a membrane
Active Transport
Movement of a substance through a cell membrane against the osmotic gradient; that is, from an area of lesser concentration to an area of greater concentration, opposite to the normal direction of diffusion
Facilitated Diffusion
Diffusion of a substance, such as glucose, through a cell membrane that requires the assistance of a “helper” or carrier protein
Osmolality
The concentration of solute per kilogram of water
Osmolarity
The concentration of solute per litre of water (often used synonymously with osmolarity)
Osmotic Pressure
The pressure exerted by the concentration of solutes on one side of a membrane that, if hypertonic, tends to pull water (cause osmosis) from the other side of the membrane
Oncotic Force
A form of osmotic pressure exerted by the large protein particles, or colloids, present in blood plasma. In the capillaries, the plasma colloids tend to pull water from the interstitial space across the capillary membrane into the capillary.
AKA Colloid Osmotic Pressure
Hydrostatic Pressure
Blood pressure or force against vessel walls created by the heart beat. Hydrostatic Pressure tends to force water of the capillaries into the interstitial space
Filtration
Movement of water out of the plasma across the capillary membrane into the interstitial space
Net Filtration
The total loss of water from blood plasma across the capillary membrane into the interstitial space. Normally, hydrostatic pressure forcing water out of the capillary is balanced by oncotic force pulling water into the capillary for a net filtration of zero.
pH
Abbreviation for potential of hydrogen. A measure of relative acidity or alkalinity. Since the pH scale is inverse to the concentration of acidic hydrogen ions, the lower the pH, the greater the acidity; the higher the pH, the greater is the alkalinity. A normal pH range is 7.35 to 7.45
Acidosis
A high concentration of hydrogen ions; a pH below 7.35
Alkalosis
A low concentration of hydrogen ions; a pH above 7.45
Three mechanisms of hydrogen ion removal
- Bicarbonate buffer system
- Respiration
- Kidney function
