Movement of molecules against a concentration gradient; requires energy
active transport
Important in cellular structures (has hydrophobic and hydrophilic ends)
phospholipid
Area between higher concentration and lower concentration where molecule passes through
gate/channel
Transports sodium ions out of cells and potassium ions into cells
Na/K pump
Molecules or other particles that are too large to enter a cell by diffusion or active transport are conveyed in a vesicle that forms a section of a cell membrane
endocytosis
Form of endocytosis where cells take in tiny droplets of liquid from their surroundings
pinocytosis
Form of endocytosis where cells take in solids
phagocytosis
Moves specific types of particles into the cell
receptor mediated endocytosis
Combines endocytosis and exocytosis to selectively and rapidly transport a substance or particle from one end of a cell to the other
transcytosis
Series of changes that a cell undergoes from the time it forms until it divides
cell cycle
Form of cell division (division of the nucleus)
mitosis
Division of the cytoplasm
cytokinesis
Cell grows and maintains its routine functions as well as contributions to the internal environment
interphase
Chromatin fibers condense, making individual chromosomes visible
prophase
Spindle fibers attach to centromeres so that a fiber accompanying one chromatid attaches to one centromere
metaphase
Centromeres of the chromatids separate, and identical chromatids are now considered individual chromosomes
anaphase
Chromosomes complete their migration towards centrioles by beginning to elongate and unwind from rodlike structures into threadlike structures
telophase
Process of specialization (cell division explains how a fertilized egg develops into an individual consisting of trillion of cells, of at least 260 specialized types)
differentiation
Ability to divide repeatedly (into two daughters cells-one stem cell and one partially specialized) which enables the body to grow and injuries to heal (self-renewal)
stem cell
Partly specialized cell that is the daughter of a stem cell but is intermediate between a stem cell and a fully differentiated cell
progenitor cell
Daughter cells can follow any of several pathways, but not all of them
pluripotent
Form of cell death that is programmed because it is a normal part of development