Download Ch. 4 | BIOL 140 - Organization/Function of Cell and more Quizzes Biology in PDF only on Docsity!
Cell Theory
Was the 1st unifying theory of biology, cells are the funamental units of life, all organisms are composed of cells, all cells come from preexisiting cells. TERM 2
Surface area-to-volume ratio
DEFINITION 2 Cells are small because they need this to be high. Volume determines the amount of chemical activity in the cell per unit time, surface area determines the amount of substances that can pass the cell boundary per unit time TERM 3
Plasma membrane
DEFINITION 3 Made up of phospholipid bilayer, allows cells to maintain constant internal environment, a selectively permeable barrier, is important in communication and receiving signals, often has protein for binding with adjacent. TERM 4
Prokaryotes
DEFINITION 4 Don't have organelles, are very successful, individuals are single cells, are very small, enclosed by a plasma membrane, the DNA is contained in the nucleoid, cytoplasm consists of cytosol (water and dissolved material) and suspended particles, ribosomes-site of protein synthesis, have a rigid cell wall TERM 5
Pili
DEFINITION 5 hair like structures projecting from the surface. They help bacteria adhere to other cells
Flagella
Help the prokaryotes swim TERM 7
Organelles
DEFINITION 7 A particle that has a specific task IN the eukaryotic cell TERM 8
Eukaryotic Cell
DEFINITION 8 UP to 10 times larger than prokaryotes, have organelles, TERM 9
Compartmentalization
DEFINITION 9 Allowed eukaryotic cells to specialize-forming tissues and organs into multicellular organisms TERM 10
Nucleus
DEFINITION 10 largest organelle, contains the DNA, site of DNA replication, site of genetic control of cell activities, the nucleolous begins assembly of ribosomes
Smooth endoplasmic reticulum
(SER)
More tubular, no ribosomes, chemically modifies small molecules such as drugs and pesticides, hydrolysis of glycogen in animal cells, synthesis of lipids and steroids. TERM 17
Rough Endoplasmic reticulum (RER)
DEFINITION 17 Ribosomes are attached, segregates newly made proteins- they enter the human and can be modified and transported. TERM 18
The Golgi Apparatus
DEFINITION 18 Carry material for cell wall, receives proteins from the ER-can further modify them, concentrates packages and sorts proteins, in plant cells, polysaccharides for cell walls are synthesized. TERM 19
Cis region
DEFINITION 19 Receives vesicles (a piece of the ER that buds off) from the ER TERM 20
Trans region
DEFINITION 20 Vesicles bud off from the golgi apparatus and are moved to the plasma membrane
Lysosomes
Originate in the Golgi apparatus, contain digestive enzymes- macromolecules are hydrolyzed into monomers. TERM 22
Phagocytosis
DEFINITION 22 Digest enzyemes. A phagosome is formed which fuses with a primary lysosome, forming a secondary lysosome. TERM 23
Mitochondira
DEFINITION 23 Energy in fuel molecules is transformed to the bonds of energy-rich ATP; cellular respiration. Cells that require a lot of energy have a lot of mitochondria. Not in prokaryotes TERM 24
Centrioles
DEFINITION 24 NOT in plant cells; only in animal TERM 25
Plastids
DEFINITION 25 Occur only in plant and some protists
Vacuoeles
Store waste products and toxic compounds-may deter herbivores, provide structure for plant cells-turgor, store anthocyanins (pink and blue pigments) in flowers and fruits, digestion in seeds-vaccuoles have enzymes to hydrolyze store food for early growth, TERM 32
Cytoskeleton
DEFINITION 32 Supports and maintains shape, allows some types of movement, positions organelles, some fibers act as support for motor proteins, interacts with extracellular strucutres to hold cell in place. Has 3 components: microfilaments, intermediate filaments, microtubles TERM 33
Microfilaments
DEFINITION 33 Under membranes, help a cell or parts of a cell to move, determine cell shape, made from the protein actin, actin has
- and - ends and polymerizes to form long helical chains (reversible) TERM 34
Intermediate
filaments
DEFINITION 34 Many different kinds, made of fibrous proteins of the keratin family, stabilize cell structure and resist tension TERM 35
Microtubles
DEFINITION 35 Form rigid internal skeleton in some cells, act as tracks along with motor proteins move, made from protein tubulin-a dimer, have + and - ends, can change length rapidly by adding or losing dimers
Cilia
Short, usually many present, move with still power stroke and felxible recovery stroke TERM 37
Flagella
DEFINITION 37 Longer, usually one or two present, movement is snake like TERM 38
Dynein
DEFINITION 38 Binds to microtuble doublets and allows them to slide past eachother. Grabs down and picks up movement TERM 39
Kinesin
DEFINITION 39 Binds to a vesicle and "walks" it along by changing shape. Walks where it goes TERM 40
Extracellular matrix
DEFINITION 40 Holds, cells together in tissues, contributes to properties of bone, cartiliage, skin, orient cell movements in development and tissue repair, plays a role in chemical signaling
