Cell Physiology Flashcards
(31 cards)
Are free-floating ribosomes that produce proteins that are important to the structure of the cell & some enzymes necessary for cellular activity.
Free Ribosomes
Prepare hormones or other substances for secretion by processing them & packaging them in vesicles to be moved to cell membrane for excretion.
Produce lysosomes & store other synthesized proteins & enzymes until they are needed.
Golgi Apparatus
Membrane-covered organelles that contain specific digestive enzymes that break down PNCL.
Responsible for digesting worn or damaged sections of a cell when membrane ruptures & cell dies.
Form a membrane around any substance that needs to be digested & secrete digestive enzymes directly into the isolated area, protecting the rest of the cytoplasm from injury.
Lysosomes
Movement of substances (waste products, hormones, neurotransmitters) out of the cell.
Exocytosis
engulfing of specific substances that have reacted with a receptor site on the cell membrane.
Pinocytosis
allows cell, usually a neutrophil or macrophage, to engulf a bacterium or a foreign protein and destroy it within the cell by secreting digestive enzymes into the area.
Phagocytosis
Destruction of engulfed proteins or bacteria.
Removing substances from a cell by pushing them through cell membrane.
Hormones, neurotransmitters, enzymes, & other substances produced within a cell are excreted into the body by this process.
Endocytosis
The process of maintaining stable conditions inside a cell.
Homeostasis
Main goal of cell:
To maintain homeostasis
are used to achieve homeostasis.
Active & Passive transport
happens w/o expenditure of energy & can occur across any semipermeable membrane.
Passive transport
requires energy input from cell to move substance against its concentration gradient.
Active transport
Movement of substance from higher concentration to lower concentration.
Substances that move by diffusion include sodium, potassium, calcium, carbonate, oxygen, bicarbonate, & water.
Small substances & materials w/ no ionic charge move most freely thru the channels.
Substances w/ negative charge move more freely than substances w/ positive charge.
Diffusion
Movement of water across a semipermeable membrane from an area that is low in dissolved solutes to one that is high in dissolved solutes.
Osmosis
pressure created when diffusion of water across a cell membrane from an area of high concentration (of water) to an area of low concentration.
Water equalize dilution of the solutes.
Osmotic pressure
fluid that contains the same concentration of solutes as human plasma.
Isotonic Solution
fluid that contains a higher concentration of solutes than human plasma
Hypertonic Solution
fluid that contains a lower concentration of solutes than human plasma.
Hypotonic solution
Movement of substance from higher concentration to lower concentration assisted by a carrier (no energy required).
Carriers may be hormones, enzymes, or proteins.
Facilitated diffusion
Movement of substance from lower to higher concentration, requires energy.
Kidney cells use active transport to excrete drugs from the body, as well as to maintain electrolyte and acid–base balances.
Active transport
Most cells have ability to reproduce themselves thru
Mitosis
Genetic makeup of cell determines the rate at which it multiplies.
Cell cycle
Cells that reproduce very quickly
Cells of GIT lining (72 hours)
Cells that reproduce very slowly
Breast tissues (few months)