Cells Flashcards
Plasma Membrane
- flexible yet sturdy barrier between intercellular and extra cellulaar
- contain cytoplasm
- comprised of phosphlipds and several proteins
Membrane permaebility
- selectivley permeable
- lipid bilayer always permeable to small nonpolar, uncharged molecules e.g. O2, CO2
- transmembrane proteins act as channels
- macrocmolecules can only pass by vesicular transport
Nucleus
controls actions in the cell. contain DNA (Chromatin)
Lysosome
breaks down food, waste, and worn out cells parts
Cytoplasm
fluid material that takes up space between the nucleus and cell membrane, holds the contents of the cell (organelles)
nuclear membrane
controlls what entres and exits the cell’s nucleus
cell membrane
controlls what entres and leaves the cell
Vacuole
storage sac for water, nutrients, and watse
Mitochondrion
produces energy (ATP) used by the cell from glucose
Ribosomes
produce proteins
cell wall
ridgid barrier provides protection, support, structure
Nucleolus
located inside nucleus, where ribosomes are made
Chomatin (Chromosomes)
contains the cell’s genetic material
Golgi Body
processes and packages proteins and lipid molecules
Passive Processes
- simple diffusion
- facilitated diffusion
- osmosis
Active Processes
- active transport
- vesicular
Osmosis
diffusion of water molecules from low to high conc. through a semi-permerable membrane
- no ATP
- dilution effect
Active Transport
Energy derived from ATP changed the shape of a transporter protein which pumps a substance across a plasma membrane against its concentration gradient
Simple Diffusion
- does not require ATP
- high -> low conc
Facilitated Diffusion
- high -.> low conc.
- uses channels
Vesicular Transport
predominant mechanism for exchange of proteins and lipids between membrane-bound organelles
Smooth ER
produces lipids, phospholipids, and steroids
Rough ER
has ribosomes attached. produces proteins
Concentration Gradient
the diff in conc. of a chemical inside & outside of the plasma membrane
Electrical Gradient
the dff in conc of ions between inside & outside the plasma membrane
Concentration gradient + electrical gradient =
electrochemical gradient
cytoskeleton
microtuble and filaments/ maintains shape and internal organisation. aids in division, movement, & structure
Nuclear Envelope
highly regulated membrane barrier that separates the nucleus from the cytoplasm
Nuclear Pores
protein-lined channel in the nuclear envelope that regulates the transportation of molecules between the nucleus and the cytoplasm
Cytosol
semi-fluid substance filling interior of cell and is the site of multiple cell processes
Free ribosomes
ribosomes not attached to ER Free ribosomes synthesize proteins that are released into the cytosol
Proteins of Plasma Membrane
- Cholesterol
- Transmembrane Proteins
- Peripheral Proteins:
- Glycolipids and Glycoproteins:
role of Cholesterol in Plasma Membrane
provides structure and sturdiness
role of Transmembrane Proteins in Plasma Membrane
allow entry and exit of molecule into and out of the cell
role of Peripheral Proteins in Plasma Membrane
signals what is going in and out of cell
role of Glycolipids and glycoproteins in Plasma Membrane
maintain sability. cell-to-cell recognition. signal to immune cells
concentration gradient
the difference in the concentration of a chemical between one side of the plasma membrane and the other. movement of solutes, distribution of the number of specific moelcules
electrical gradients:
is the difference in concentration of ions between one side of the plasma membrane and the other. distribution of positivley and negativley charged ions
electrochemical gradient
concentration + electrical gradients
