Deck 5 Flashcards
prokaryotic cell
small, simple, single-cell organisms; bacteria are the most prevalent kind. Do not contain a nucleus or any other organelle.
protist
Single-celled eukaryote.
ribosome
the molecular machines that use the instructions contained in the DNA to build all the proteins needed by the cell.
vacuole
specialized mainly for storage. Their membranes do not fuse with the membranes of other cellular components.
vesicle
specialized for transport and some other functions. Their membranes can fuse with the plasma membrane, allowing them to empty their contents into the extracellular space. Also may fuse with the membranes of the endoplasmic reticulum and Golgi apparatus, allowing them to empty their contents into those organelles.
endomembrane system
describes a set of membranous structures found in eukaryotic cells that are related to the synthesis, packaging, and distribution of cellular molecules. includes the endoplasmic reticulum (rough and smooth), the Golgi apparatus, and vesicles.
glycolipid
role is to maintain the stability of the cell membrane and to facilitate cellular recognition, which is crucial to the immune response and in the connections that allow cells to connect to one another to form tissues.
integral protein
In order to carry out their functions, some proteins need to be embedded in the membrane. These proteins are called_____.
peripheral protein
Proteins that are attached to the inner or outer surface of a membrane are called ____.
phospholipid bilayer
the fabric of the membrane. The structure causes the membrane to be semipermeable. The hydrophobic core blocks the diffusion of hydrophilic ions and polar molecules. Small hydrophobic molecules and gases, which can dissolve in the membrane’s core, cross it with ease.
sterol
used by some cells to maintain proper membrane fluidity.
Active Transport
moving molecules against their concentration gradient. This is a non spontaneous process and requires the cell to do work to move the ions “uphill” against the concentration gradient. To do work, the cell must expend energy and actively move (pump)the ions.
Concentration gradient
the process of particles, which are sometimes called solutes, moving through a solution or gas from an area with a higher number of particles to an area with a lower number of particles. The areas are typically separated by a membrane.
diffusion
The passing of molecules through the membrane into the cell.
endocytosis
material is engulfed within an infolding of the plasma membrane and then brought into the cell within a cytoplasmic vesicle.
exocytosis
an internal vesicle fuses with the plasma membrane and releases its contents to the outside.
facilitated diffusion
The process of moving impermeable molecules across a membrane (down their concentration gradients) using channels or pores is referred to as _____ ________.
osmosis
a process by which molecules of a solvent tend to pass through a semipermeable membrane from a less concentrated solution into a more concentrated one, thus equalizing the concentrations on each side of the membrane.
selective permeability
The cell membrane provides a semipermeable barrier between the inside and the outside of the cell. The phospholipid bilayer structure of the membrane allows selected ions and organic molecules to pass through the plasma membrane and regulates the movement of molecular substances.
simple diffusion
both large and small molecules spontaneously move from areas of high concentration to areas of low concentration following random movements, referred to as Brownian motion.
transport protein
a protein that serves the function of moving other materials within an organism.
anabolic reaction
any chemical reaction that combines simple molecules to build more-complex molecules
catabolic reaction
any chemical reaction that breaks down complex molecules into simpler molecules
cellular respiration
the process by which cells use oxygen to produce energy from food
Chlorophyll
A green pigment found in the chloroplasts of plants, algae, and some bacteria
Combustion
A rapid reaction between oxygen and fuel that results in fire
Fermentation
Process by which cells release energy in the absence of oxygen
metabolic pathway
begins with a specific molecule and ends with a product
Photosynthesis
Conversion of light energy from the sun into chemical energy.
Pigment
A colored chemical compound that absorbs light, producing color.
