Page 33 - 84 human physiolofy part-1

Cell Physiology

instead of through a duct

Endocytosis: the capture of a substance outside the cell when the plasma membrane merges to
engulf it

Endoplasmic Reticulum: organelle that play an important role in making proteins and shuttling
cellular products; also involved in metabolisms of fats, and the production of various materials

Epithelial Cells: cells that aid in secretion, absorption, protection, trans-cellular transport,
sensation detection, and selective permeability

Exocrine Cells: cells that secrete products through ducts, such as mucus, sweat, or digestive
enzymes

Exocytosis: the process of vesicles fusing with the plasma membrane and releasing their contents
to the outside of the cell

Facilitated Diffusion: the diffusion of solutes through channel proteins in the plasma membrane

Golgi Apparatus: "packages" cellular products in sacs called vesicles so that the products can
cross the cell membrane and exit the cell

Glycolysis: process in which sugars (glucose) are converted to acid

Lysosomes: sac-like compartments that contain a number of powerful degradative enzymes

Microfilaments: provide mechanical support for the cell, determine the cell shape, and in some
cases enable cell movements

Microtubules: function as the framework along which organelles and vesicles move within a cell

Mitochondria: the organelles that function as the cell "powerhouse", generating ATP

Nucleus: controls the cell; houses the genetic material

Organelles: bodies embedded in the cytoplasm that serve to physically separate the various
metabolic activities that occur within cells

Osmosis: the diffusion of water molecules across a selectively permeable membrane from an area
of high solute concentration to an area of low solute concentration.

Passive Transport: the movement of substances down a concentration gradient and does not
require energy use

Peroxisomes: organelles in which oxygen is used to oxidize substances, breaking down lipids and
detoxifying certain chemicals

Phagocytosis: a form of endocytosis wherein large particles are enveloped by the cell membrane
of a (usually larger) cell and internalized to form a phagosome, or "food vacuole." In animals,

Wikibooks | 33