Cell Theory
All living things are composed of cells and that all cells come from other cells
Prokaryotic Cells
Basteria and archaea
Eukaryotic Cells
Protists, fungi, plants, and animals
Plasma membrane
Forms a boundary between a living cells and its suroundings and controls the traffic of materials into and out of the cell.
Membrane are made out of
Phospholipids are the main components. It has two distinct regions: a negatively charged/hydrophilic phosphate group (head) and two nonpolar, hydrophobic fatty acid tails
Chromosomes
Carrying genes made of DNA
Ribosomes
Tiny structures that make proteins according to instructions from the genes
Cytoplasm
The entire region between the nucleus and the plasma membrane
Nucleoid
The region in a prokaryotic cells where the DNA is coiled up
Flagella
Long projections that may propel the prokaryotic cell through its liquid environment. Present in sperm cells in eukaryotic cells
Organelles
Membrane-bound structures perform specific functions in the cell
Cellular Metabolism
Chemical activities of the cell
Nucleus
Contains most of the cells DNA and controls the cell's activities by directing protein synthesis.
Chromatin
A complex of proteins and DNA
Nuclear Envelope
A double membrane perforated with protein-lined pores that control the flow of materials into ando out of the nucleus
Nucleolus
The site where a special type of RNA called ribosomal RNA (rRNA) is synthesized according to the instructions in the DNA
Endomembrane system
Includes the nuclear envelope, endoplasmic reticulum, Golgi apparatus, lysosomes, vacuoles, and the plasma membrane
Vesicles
sacs made of membrane, helps with the transfer of membrane segments
Endoplasmic Reticulum (ER)
Extensive network of flattened sacs and tubules. The membranes are continuous with the nuclear envelope
Smooth ER
Synthesis of lipids, including oils, phospholipids, and steroids. Helps to process drugs and other potentially harmful substances. Stores calcium.
Rough ER
Makes more membrane, phospholipids are made by enzymes. Has ribosomes attached to its surface.
Glycoproteins
Short chains of sugars are often linked to the polypeptide.
Transport vesicle
Packaged molecules ready for export from the ER
Golgi apparatus
Consists of flattened sacs stracked on top of each other. Performs several functions in close partnership with the ER. Receives and modifies products manufactured by the ER. Vesicles on the other side bud off and travel to other sites.
Lysosomes
Consists of digestive enzymes enclosed in a membranous sac. The enzymes are made by rough ER and then transferred to the Golgi apparatus for further procesing.
Vacuoles
Membranous sacs that have a variety of functions
Central Vacuole
Helps a cell grow in size by absorbing water and enlarging, and it can store vital chemicals or waste products
Peroxisome
An organelle that is not part of the endomembrane system but, is involved in various metabolic finctions. Including the breakdown of fatty acids to be used as fuel and the detoxification of alcohol and other harmful substances.
Mitochondria
Organelles that carry out cellular respiration in nearly all eukaryotic cells, converting the chemical energy of foods such as sugars to the chemical energy of a molecule called ATP
Intermembrane space
The narrow region between the inner and outer membranes.
Mitochondrial matrix
Enclosed by the inner membrane, contains the mitochondrial DNA and ribosomes, as well as many enzymes that catalyze some of the reactions of cellular repiration.
Chloroplasts
photosynthesizing organelles of all photosynthetic eukaryotes.
Stroma
Thick fluid inside the inner membrane that contains the chloroplast DNA and ribosomes as well as many enzymes
Thylakoids
A network of interconnected sacs inside the chloroplast
Granum
A stack of thylakoids
Endosymbiosis
Proposes that mitochondria and chloroplasts were formerly small prokaryotes that began living within another cell
cytoskeleton
Network of protein fibers, extending thoughout the cytoplasm of a cell
Microfilaments
Solid rods composed mainly of globular proteins called actin, arranged in a twisted double chain.
Intermediate filaments
Made of various fibrous proteins and have a ropelike structure. Reinforce cell shape and to anchor certain organelles.
Microtubules
Hollow tubes composed of globular proteins called tubulins
Centrioles
Come in pairs and are within the centrosome
Cilia
Short, numerous appendages that propel protists
Basal Body
Nine microtubule triplets arranged in a ring. Act as a foundation for microtubule assembly from tubulin subunits.
Extracellular Matrix (ECM)
A product of animal cells. The layer helps hold cells together in tissues and protects and supports the plasma membrane
Intergrins
Span the membrane, attaching on the other side to proteins connected to microfilaments of the cytoskeleton
Tight junctions
Forming continuous seals around cells, they pervent leakage of extracellular fluid across a layer of epithelial cells
Anchoring junctions
Function like rivets, fastening cells together into strong sheets. Intermediate filaments made of sturdy keratin proteins anchor these junctions in the cytoplasm
Gap junctions
Channels that allow small molecules to flow through proteinlined pores between neighboring cells.
Cell Wall
Rigid extracellular structure not only protects the cell but provides the skeletal support and keeps plants upright on land.
Plasmodesmata
Channels between adjacent plant cells, form a circulatory and communication system connecting the cells in plant tissues.