Chapter 7 Objectives Flashcards
What makes up the prokaryotic cell structure?
- Plasma Membrane
- Chromosome nucleoid
3.Plasmids (Small DNA molecules) - Ribosomes (RNA molecules & proteins)
- Flagella (tail!)
- Cytoskeleton - long fibrous structure
cell wall (glyco-lipids)
What are key differences between prokaryotic and eukaryotic cells?
Eukaryotic are 10x larger than prokayotic cells
Eukaryotic have compartmentalization with membrane bound organelles like the nucleous, ER, and mitochondria.
What is the nucleoid?
It is the “center” of the prokaryotic cell that hold 1 single chromosome made up of 1 large DNA molecule and small number of proteins. It is highly compact, supercoiled helix - but has no membrane that eukaryotic cells have around their nucleus.
What is cyotplasm? cytosol?
Cytoplasm is all of the contents of a cell, excluding the nucleus, bounded by the plasma membrane.
They cytosol is the fluid portion of they cytoplasm.
Ribosome
Components: Complex of RNA and proteins
Function: Protein synthesis
*no membrane
Plasma membrane
Components: Phospholipid bilayer with transport and receptor proteins
function: selective permeability, maintains intracellular environment
* single membrane
Nucleus
Components: Chromosomes, Nucleolus, Nuclear lamina
Function: Genetic information, assembly of ribosome subunits, structural support
*Double membrane (nuclear envelope with nuclear pores)
Nucleolus
Components: ribosomal subunits
Function: RNA molecules that make up ribosomes are manufactured & assembled
*inside the nucleus - no membrane of its own
Nuclear Pores
An opening in the nuclear envelope that connects the inside of the nucleus with the cytoplasm and through which molecules such as mRNA and some proteins can pass
Nuclear Lamina
a lattice like sheet of fibrous nuclear lamins, which are one type of intermediate filaments. Lines the inner membrane of the nuclear envelop, stiffening the envelope and helping organize the chromosomes
endomembrane system
A system of organelles in eukaryotic cells that performs most protein and lipid synthesis. Includes the ER, Golgi apparatus, and lysosomes
Rough Endoplasmic Reticulum (RER)
Components: Branching sac network with attached ribosomes
Function: Protein synthesis and processing
*Single membrane with receptors for entry of selected proteins
Golgi Apparatus
Components: stack of flattened cisternae
Function: Protein processing & packaging
*Single membrane and contains receptors for products of the RER
Smooth Endoplasmic Reticulum
Components: Network of branching sacs and Enzymes for synthesizing lipids
Function: LIPID synthesis
*Single membrane with enzymes for synthesizing phospholipids
Lysosomes
Components: Acid hydrolases (catalyze hydrolosis reactions)
Function: digestion and recycling
*single membrane with proton pumps