Chapter 2 - The Cell Flashcards
Light Microscopy
uses light to magnify and view cellular structure up to 2000x their sizes
Electron Microscopy
uses electrons to magnify cells up to 2 million times their size
Plasma Membrane (cell membrane)
Contains : Lipid bilayer ; phospholipids, steroids, proteins, and carbs
Function : isolates; protects, senses, supports, controls permeability of material
Cytosol
Contains : fluid part of Cytoplasm
Function : sorts by diffusion , stores glycogens, pigments, etc
Cytoskeleton
Contains : microtubules, Microfilaments
Functions : strength and support , moves cell structures
microvilli
Contains : extensions of microfilaments
Functions : increases surface area of cell for absorption
Centrosome
Contains : centrioles ( 9 microtubule triplets)
Functions : movement of chromosomes during cell division
Cilia
Contains : extensions of microtubules
Functions : moves materials over cell surface
Ribosomes
Contains : RNA + proteins ; attached ribosomes bound to Rough ER & free ribosomes released into cytoplasm
Functions : makes proteins
Mitochondria
Contains : double membrane, inner membrane folds of cristae lined with enzymes
Functions : makes 95% of ATP
Nucleoplasm
Contains : nucleotides, enzymes, nucleoproteins, and chromatin
Function: controls metabolism, stores and processes genetic information, controls protein synthesis
Nuclear Envelope
Contains : double-layer membrane
Functions : encases nucleolus
Nucleoli ( singular - nucleolus)
Contains : DNA and RNA
Function : site of rRNA synthesis and formation of ribosomal subunits
Endoplasmic Reticulum (ER)
Contains : network of channels throughout cytoplasm
Functions : synthesis of secretory products, storage , and transport
Rough ER
Contains : Bound ribosomes
Functions : modifies and packages new proteins
Smooth ER
Contains : the lack of ribosomes
Function : makes lipids, steroids, carbs; stares calcium ions
Golgi Apparatus
Contains : stacks of flattened cisternae chambers
Functions : stores, alters, and packages secretory products and lysosomal enzymes
Lysosomes
Contains : vesicles filled with digestive enzymes
Functions : removes damaged organelles or pathogens
Peroxisomes
Contains : vesicles filled with degradative enzymes
Functions : catabolizes fats; neutralizes toxic compounds
Passive Processes
- Do not require or utilize cellular energy
- Diffusion, Osmosis, and Facilitated Diffusion
Diffusion
- the movement from an area of high concentration to an area of low concentration
- Molecules move down a concentration gradient ( difference between high and low concentration)
- Gasses, small molecules/ions, lipid soluble molecules
Osmosis
- diffusion of water across a selective permeable membrane
- lower water concentration diffuses to a high solute concentration
- Water only
Facilitated Diffusion
- solutes are transported across the plasma membrane by a carrier protein
- follows concentration gradient
- carries large molecules (e.g. glucose and amino acids)
Active Processes
- Require ATP or other energy
- Active Transport, Endocytosis, Exocytosis
Active Transport
- Doesn’t follow concentration gradient
- Exchanges pumps
- Energy moves solutes out of the cell, causing other solutes to move in ( 2 Potassium in : 3 Sodium out)
- Sodium-Potassium Pump
Endocytosis
Packaging of Extracellular materials into a vesicle that imports into the cell
Pinocytosis
- vesicles formed at plasma membrane bring ECF and small molecules into the cell
- “Cell Drinking”
Phagocytosis
- Vesicles bring solid particles into the cell
- “Cell Eating”
- Bacteria, viruses, cell debris
receptor-mediated Endocytosis
- molecules bind to receptor proteins on membrane surface
- Triggers vesicles formation
- membrane folds inward to form pits
Exocytosis
- release of fluids/solids from cells when intercellular vesicles fuse with membrane
- requires ATP and calcium ions
