Cytoplasm

Cytoplasm is composed of

Cytosol, Inclusions, and Organelles

Cytosol

gel-like solution made up of water and soluble molecules

Inclusions

insoluble molecules; vary with cell type

Organelles

metabolic machinery structures of cells, each with specialized function, either membranous or nonmembranous

5 important Membranous organelles

Mitochondria, Endoplasmic reticulum, Golgi apparatus, Peroxisomes and Lysosomes

3 important Nonmembranous organelles

Ribosomes, Cytoskeleton, and Centrioles

Mitochondria

membranous organelle that produces ATP via aerobic (oxygen-requiring) cellular respiration

cristae

Enclosed by double membranes; inner membrane has many folds and play a role in cellular respiration

Ribosomes

Nonmembranous organelles that are site of protein synthesis

two forms of ribosomes

Free ribosomes (free-floating)

Membrane-boundribosomes (attached to membrane of ER)

two varieties of Endoplasmic Reticulum

Rough ER and Smooth ER

Rough Endoplasmic Reticulum

membranous organelle that is the site of protein and lipid synthesis

Smooth Endoplasmic Reticulum

membranous organelle that is the site lipid synthesis, storage and release of calcium, and detoxification of certain chemicals

Golgi Apparatus

membranous organelle that modifies, concentrates, and packages proteins and lipids received from rough ER

three Golgi apparatus pathways of transport vesicle

Secretory vesicles, Lipid vesicles, and lysosomes vesicles

Secretory vesicles

Proteins fuse with the plasma membrane for exocytosis (out the cell).

Lipid vesicles

Vesicles fuse with membranes, inserting contents (in the cell).

lysosomes vesicles

Lysosomes hold digestive enzymes in vesicles until needed.

Peroxisomes

Membranous organelle sacs containing detoxifying substances that neutralize toxins and play a role in breakdown and synthesis of fatty acids

oxidase detoxifiers

uses oxygen to convert toxins to hydrogen peroxide (H₂O₂), which is itself toxic

catalase detoxifiers

converts H₂O₂ to harmless water

Lysosomes

Membranous organelle bags containing digestive enzymes and autolysis

autolysis

Intracellular release in injured cells causes them to digest themselves

Cytoskeleton

Nonmembranous organelles that play a role in cell structure

Three types of cytoskeleton

Microfilaments, intermediate filaments, and Microtubules

Microvilli

fingerlike extensions of plasma membrane that project from surface of select cells used to increase surface area for absorption