2.1: Cell Structure

Extracellular Matrix

system surrounding a cell

Cytoskeleton

organelle used for cell shape, internal structure, movement and cell division. Made of microfilaments and microtubules.

Eukaryotic

Cell type with membrane bound nucleus

Plant cells

Cells that have a cell wall, plastids, larger vacuole

Cytoskeleton

used for cell shape, internal structure, movement and cell division

Nucleus

first part of Endomembrane system, DNA → RNA → through Nuclear pores → into Cytosol

Nuclear Membrane

Double membrane of 2 lipid bi-layers. Contains proteins that are receptors, transporters & spanners. Restricts access to DNA.

Nucleoplasm

vicious fluid similar to cytosol

Nucleolus

Dense, irregularly shaped region, Sub-units of ribosomes are assembled here from proteins and RNA.

Chromatin

DNA & associated proteins in nucleus

Endomembrane system

system of interacting organelles. Make lipids, enzymes & proteins for secretion/insertion into cell membrane. Sent out through vesicles.

Nucleus

Contains & protects almost all the DNA - separated from cytosol or metabolic processes that may damage it. Makes ribosome units. Membrane bound. Think: Pearl in oyster

Rough ER

RNA in Cytosol translated into Polypeptide chains (by ribosomes), then chains enter

Vesicles

travelers that bud from ER carrying polypeptide chains to Golgi bodies, some go through interior of Rough ER and end up in Smooth ER

Smooth ER

proteins (polypep chains) from here are packaged into Vesicles and sent off to Golgi body, some stay to become enzymes that assemble lipids or deactivate toxins

Golgi body

proteins are modified into final form and sorted, new vesicles carry them to plasma membrane or lysosomes

Plastids

membrane-bound organelle that is involved in photosynthesis and storage in plants and algae

Chromoplasts

stores pigments other than chlorophyll

Amyloplasts

stores starch

Cell junctions

way of cell to interact with another

Chloroplasts

double membrane, holds enzymes and pigments for photosynthesis - in stroma

Endoplasmic Reticulum

Creates new polypeptide chains and sometimes enhances them into lipids or enzymes. Membrane bound. Extension to nuclear envelope. Repeated, flat folds.

Golgi body

Vesicles fuse and empty here. Put finishing touches on chains like phosphates and sugars to make membrane proteins and then shipped of to plasma membrane or lysosomes. Membrane boud. Stack of pancakes.

Transport/Secretory

Type of vesicle. Marble-like structures. Membrane bound. Transport within the cell or releases them from the cell.

Mitochondrion

Has its own DNA. Makes ATP. Basically an aerobic bacteria that got comfortable. Membrane bound. Looks like a kidney bean or a small, wrapped baby.

Lysosomes

Type of vesicle, containing powerful digestive enzymes. Carry disposals. Recycling centers.

Peroxisome

Type of vesicle, contains catalase for fatty or amino acids

Vacuole

Type of vesicle, Vesicle that stores waste and aids in cellular metabolism and water balance. Maintains pressure. Garbage bins.

Ribosome

assemble polypeptide chains, NOT membrane bound, folded ribbon

Centriole

Makes tubules for cell division, NOT membrane bound, Two pills or logs lying on top of each other

Prokaryotic cells

no nuclear membrane, no mitochondria

proteins and DNA in the nucleus

Subunits of ribosomes are assembled from