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63 terms

Cell Structure and Function

STUDY
PLAY
Creators of the Cell Theory
Schleiden (Botanist), Schwann (Zoologist), Virchow (Physician)
Cell Theory
1- All living things are composed of cells 2- The cell is the basic unit of life 3- All cells come from pre-existing cells
Unicellular Organisms
Consist of only one cell ex) bacteria, amedba, paramecium
Multicellular Organisms
Consists of many cells
Cytology
Study of cells
Robert Hooke
Examined slice of cork, came up with term "cell"
Plasma Membrane
AKA cell membrane, holds cellular contents together, semi-permeable
Semi-Permeable
Only allows certain substances to enter and leave the cell
Molecules Found in the Plasma Membrane
Lipids, Proteins, Cholesterol, Carbohydrates
Phospholipid Bilayer
Cell Membrane
Hydrophilic
Water loving
Hydrophobic
Fear of water
Organelles
Little organs
Nucleus
Control Center
Nuclear Membrane
AKA Nuclear envelope, two membranes forming a boundary around the nucleus with pores, semi-permeable
Nucleolus
Composed of chromatin (DNA) and protein, where ribosomes are produced
Chromosomes
Contains hereditary information
Cytoplasm
all organelles and materials between the cell membrane and the nucleus
Cytosol
Protein rich semi-fluid substance located outside the nucleus and inside the cell membrane (70% Water, 30% Protein {Fats, Carbohydrates})
Endoplasmic Reticulum (ER)
supports other organelles, prepares proteins for secretion, transport materials within a cell
Rough ER
Ribosomes attached to surface
Smooth ER
Ribosomes not attached to surface
Ribosomes
"Protein Factory" produces proteins
Golgi Bodies
temporary storage place for proteins, modifies proteins, collects, packages, distributes molecules, structure consists of small groups of parallel membranes
Mitochondria
"Power House" controls the release of energy
Cristae
Folded inner membrane of a Mitochondria
Lysosomes
"Suicide Sac" found only in animal cells
Centrioles
Functions in cell reproduction, only in animal cells
Vacuoles
"Storage Room" stores materials such as water, slats, proteins, and carbohydrates
Cytoskeleton
Internal support system of the cell composed of microtubules and microfilaments
Microtubules
Cylindrical protein material
Microfilamets
Long, thin fibers that function in movement or support of the cell
Cell Wall
composed of Cellulose around the cell membrane, found in plants, fungi, and some unicellular organisms
Middle Lamella
thin plate composed of pectin (plysaccharide) between adjacent plants cells
Chloroplast
contains chlorophyll (green) used to trap light energy and convert to chemical energy
Chromoplast
contains red, orange, or yellow pigments giving fruits and flowers their color
Xanthophyll
yellow pigment
Carotene
red and orange pigment
Leukoplasts
Colorless plastid where starch molecules are found
Vacuole
plants cells have a single large vacuole that stores water, salts, proteins, and carbohydrates
Homeostasis
Steady state an organism maintains by self-regulating adjustment
Internal Change Example
Exercise increases the bodies need for oxygen
External Change Example
Temperature, water and food supply, predator escape (stress)
What determines what can enter and leave the cell?
1-Size of molecule 2-Structure of cell membrane 3-Conditions inside/outside the cell 4-Solubility of the substance in water
Diffusion
movement of molecules from an area of high concentration to an area of low concentration
Permeable
If a particular substance is able to diffuse across a membrane
Influences on Diffusion
Concentration, Temperature, Pressure
Penetrate Rapidly
Gases, Water, Fat Solvents
Penetrate Slowly
Monosaccharides, Amino Acids, Fatty Acids, Glycerol
Penetrate Very Slowly
Disaccharide
Little or No Penetration
Polysaccharides, Proteins, Lipids
Hypertonic
Higher concentration of solutes than the solution to which it is being compared
Solute
molecular particulars other than water
Osmosis
Diffusion only referring to water
Hypotonic
Solution that contains a lower concentration of solutes than the solution to which it is being compared
Isotonic
solute concentration the same inside and outside the cell
Active Transport
Requires energy, from low to high concentration
Facilitated Diffusion
Passive transport, increases rate of diffusion using carrier proteins
Transport Vesicles
Process of molecules entering the cell through indented areas of plasma membrane
Endocytosis
transport of molecules into the cell by transport vesicles (energy)
Phagocytosis
engulfing particles into the cell by use of cytoplasmic extensions
Exocytosis
transport molecules out of the cell by vesicles
Pinocytosis
Tiny pockets form along the cell membrane that fill with liquid to form vesicles