Biology Chapter 7 Cell Structure Flashcards
net movement of particles from an area where there are many particles of the substance to an area where there are few particles of the substance
diffusion
molecules and ions continue to move and collide but no change in concentration occurs
equilibrium
diffusion of water through a selectively permeable membrane
osmosis
A solution with the same concentration of water and solutes as inside a cell, resulting in the cell retaining its original shape because there is no net movement of water
isotonic
a solution that has a higher concentration of solute outside the cell than inside the cell, causing water to leave the cell by osmosis
hypertonic
a solution that has a lower concentration of solute outside the cell than inside the cell, causing water to flow into the cell by osmosis
hypotonic
energy-requiring process by which substances move across the plasma membrane against a concentration gradient
active transport
energy-requiring process by which a cell expels wastes and secretes substances at the plasma membrane
exocytosis
Bi-layer made up of phospholipids; a thin, flexible barrier around a cell; regulates what enters and leaves the cell
cell membrane
strong supporting layer around the cell membrane in plants, algae, and some bacteria
cell wall
the property of a membrane that allows some materials to pass through while keeping others out
selectively permeable
the basic structural and functional unit of all living things
cell
prokaryotic, contains no nucleus, no membrane bound organelles
bacteria cell
complex cellular organization: organelles; single or multicellular organisms; newer on the evolutionary scale
eukaryotes
The energy-requiring process that moves material across a cell membrane against a concentration difference
active transport
Diffusion of water through a selectively permeable membrane
Osmosis
the movement of substances across a cell membrane without the use of energy by the cell
passive transport
when certain types of substances pass through the cell membrane more easily then others
selectively permeable
Powerhouse of the cell, organelle that is the site of ATP (energy) production
Mitochondria
A system of membranes that modifies and packages proteins for export by the cell
Golgi apparatus
site of protein synthesis
Ribosomes
Contain digestive enzymes, removes waste and foreign material from the cell
Lysomes
A part of the cell containing DNA and RNA and responsible for growth and reproduction
Nucleus
A cell that contains a nucleus and membrane bound organelles
Eukaryote
