Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
18 Cards in this Set
- Front
- Back
|
Differences between prokaryotic
cells and eukaryotic cells |
Prokaryotic Cells:
-one circular chromosome, not in a membrane -no histones -no organelles -Peptidoglcan Cell walls -Binary fission Eukaryotic Cells: -paired chromosomes in nuclear membrane -histones -organells -polysaccharide cells walls -mitotic spindle |
|
|
Which groups does Bacteria belong to and why.
|
Backteria is a prokayote because it has no histones, no organelles, peptidoyglycan cells wells, nucleoid containing DNA.
Archaea is also a prokaryote. |
|
|
Describe bacteria shapes
|
Coccii: berry shaped.
Bacilli: rod shaped Vibrio: curved shape Spirillum: Corkscrew/rigid Spirochete: corkscrew/flexible |
|
|
For coccii, describe
the various arrangements formed by its cellular division |
Cocci: Berry Shaped. Division on one plane:
Diplococci: OO (remain in pairs) Streptococci: 000000 remain attached in chainlike patterns Two planes: TETRADS: remain in groups of four 3 planes: SACRINAE Cubelike groups of 8. Multiple planes in grapelike clusters: STAPHYLOCCI |
|
|
For bacilli describe
the various arrangements formed by its cellular division |
Bacilli: Rod Shaped. Divide only across their short axis. No multiple planes.
Diplobacilli: in pairs, two rods, Streptobacilli: in chains Coccobacilli: two attached bacilli that have shape of cocci. |
|
|
Describe structures and functions of a prokaryotic cell
|
All have Plasma Membrane:
-Encloses cytopasm. -It's a phospholipid bilayer. -Contains peripheral and integral proteins. -Has Tansmembrane proteins. -Contains enzymes to make ATP -Has photosynthetic pigments. Almost all have Cell Wall surrounding plasma membrane. -prevents cells walls from rupturing when water pressures greater than that outside the cell. -provides anchor points for flagella, and mainains shape of bacterium --Cell wall composed of peptidoglycan. Contains ribosomes, cytoplasm, nucleoid containing DNA. |
|
|
Describe external structures
of a prokaryotic cell |
--Glycocalyx: substance that maybe secreted by cell to surround itself. (sugar coat). If firly attached, it's a capsule, is loosely attached a slime layer. Negative Staining can determine a cell.
--Flagella: long filmentous appendages that propel bacteria. --Axial filaments: move spirochetes like a corkscrew --Fimbria:have tendency to adhere to each other and surfaces., form biofilms. --Pili: 1 or 2 per cell. involved in DNA transfer and motility. |
|
|
What are the differences between Gram+ and
Gram- cell walls of bacteria. |
Gram+: Cell wall consists of many layers of peptidoglycan.
Cell wall surrounds plasma membrane Gram-: Cell wall has few layers of peptidoglycan and an outer membrane. Cell wall surrounds plasma membrane, outer membrane surrounds cell wall. |
|
|
Compare Gram+, -
cell walls with archaeobacteria and mycopasmas |
Archaeobacteria: no cell walls or walls of psuedomurein.
Mycoplasmas: has no cell walls. Sterols in plasma membrane(protect them from rupturing) |
|
|
Describe the prokaryotic plasma membrane. Include fluid mosaic model |
Made mostly of phospholipids, a lipid bilayer. Less rigid than eucharyotic membranes. Can be surrounded by cell wall.
Fluid Mosaic Model: describes how plasma membrane as viscous are olive oil. Proteins move to function and phospholipids can rotate and move laterally. these do not destroy the membrane. Model of dynamic arrangement of phospholipids and proteins is the FMM. |
|
|
Functions of plasma membrane
|
Serves as a selective barrier through which materials enter and exit the cell. (Selective Permeability)
Membrane contains enzymes caoabke if oridycubg ATP. |
|
|
Describe Passive Processes that
move passage of some molecules across plasma membrane |
Passive Process - no ATP required. Substances move from high to low concentration.
--Simple Diffusion: molecules/ions move from area of high concentration to low concentration. --Facilitated diffusion: Passing of substance through membrane wall where proteins function as channels or carriers-aka (Transporter Proteins). --Osmosis: movement of solvent molecules across a membrane from high to low concentation. Solvent usually water, moves through aquaporins. See Quiz #3, question 5 |
|
|
Describe Active Transport and
Group Translocation. |
Active Transport: uses energy in form of ATP to move substances across membrane, usually against concentration gradient (low to high). Relies on transporter proteins. Substance not altered.
Group Translocation (prokaryotic only): form of active transport in which the substances is chemically altered during transport. Uses transporter proteins. |
|
|
Compare and contract overall cell structure, flagella, nucleus, ribosomes of pro and eukaryotes.
|
Cell Wall: only in plants, algae and fungi. Made of carbohydrates, not peptidglycan.
Plasma Membrane: all contain Sterols, only mycoplasma does in prokaryotes. Flagella. Cilia: Eukaryotes- contain cytoplasm and continuation of plasma membrane. PRKARYOTES- just protein extension. Nucleus: Euk-has nucleus with DNA wrapped in nuclear envelope. Nucleus is membrane enclosed. No membrane enclosure in prokaryotes - its a nucleoid. Ribososomes: Eukaryotes -80s ribosomes. Prokaryotes- 70s |
|
|
Explain an Organelle
|
A structure with specific shapes and a specialized function that is enclosed in a eukaryotic cells. Some are membrane bound, some not. NOT:
Ribosomes, centrosomes, centrioles. |
|
|
Explain functions of Endoplasmic Reticulum, Golgi Complex, Mitochondria, chloroplasts and lysosomes
|
ER: Transport network, makes proteins and lipids. Rough ER with attached ribosomes makes proteins. Smooth ER, without ribosomes, makes lipids.
Golgi Complex: membrane formationand secretion of proteins. Mitochondria: powerhouse of cellular respiration. Produces ATP Chloroplast: for photosynthesis (not in animals) Lysosomes: digestive enzyme for cleaning up unneeded items in cell. |
|
|
Describe briefly endosymbiotic
hyposthesis. |
Eukaryotic cells evolved from sybiotic prokaryotes living inside other prokaryotic cells.
Mitochondria is similar to prokaryotic cells in that it has own ribosomes that are 70s, similar to prokaryotic. Eukaryotic ribosoes are 80s. Also have own DNA, self replicate with binary fision. NO nucleus. |
|
|
Define hypertonic, isotonic
and hypotonic solutions. |
Hypertonic: A medium having a higher concetration of solutes OUTSIDE the cell than inside. Bacterial cells in this situation shrink and collapse because water leaves cells by osmosic.
Isotonic: solutes inside and outside of cell are equal. Hypnotonic: medium outside the cell has less solute than iside cell. |
