Topic 1, 9 , and 10

Cell Structure and Function

Cells

Basic structural and functional units of every organism.

All cells are;

1. Bound by plasma membrane

2. Contain cytosol

3. Contain chromosomes

4. Contain ribosomes

Prokaryotes

Cells with DNA in nucleoid region, smaller than eukaryotes, lack internal membrane - bound organelles (Bacteria and Archaea).

Eukaryotes

Cells with DNA in nucleus, contains membrane bound organelles that compartmentalize functions (Protists, fungi, animals, and plants).

Organelles

Membrane bound structure in eukaryotes.

Classifications of organelles:

Endomembrane system and energy organelles.

Endomembrane system

Organelles and subcellular components that interact (directly and via vesicles), to modify, package, and transport polysaccharides, proteins, and lipids in the cell.

Energy organelles

Convert energy to forms that cells can use for work (mitochondria and chloroplast).

Compartmentalization

Separating processes and enzymatic reactions into different locations (increases surface area and prevents interfering reactions).

Cell components of plants

Chloroplasts, central vacuole, cell wall, and plasmodesmata.

Cell components of animals

Lysosomes, centrosomes, and flagella.

Nuclear Envelope

Double membrane, has pores, continuous with ER membrane, (Nucleus contains genetic material).

Subunits

Exit via nuclear pores and assemble into ribosomes.

Protein synthesis

mRNA copies codons and rRNA pastes them into ribosome and tRNA translates them into protein.