Carbohydrates (CHO) 2 Main function: energy Monomer: monosaccharides (ex. glucose, fructose, galactose, etc.) Disaccharides: sucrose, lactose, maltose Polysaccharides: starch, cellulose, glycogen

Lipids CHO Monomers: fatty acids Hydrophobic Functions: energy- storage, waterproof coverings, cell membranes, hormones

Proteins CHON Monomer: amino acids Functions: structure, movement, defense, storage, signals, enzymes

Nucleic acids CHONP Monomer: nucleotides Functions: contain genetic material (DNA), direct protein synthesis (RNA), act as energetic molecules (ATP)

The Cell Theory Every living organism is made up of one or more cells The smallest living organims are single cells, and cells are the functional units of multicellular organisms All cells arise from preexisting cells

All cells… Have a limited size (plasma membrane) Have a: plasma membrane, cytoplasm, DNA Obtain energy and nutrients from the environment

CellsProkaryoticBacteriaEukaryoticPlantAnimal

Plasma membrane Functions: – Selectively isolate the cell’s contents from the external environment – Regulate substance exchange – Communicate and attach cells – Regulate biochemical reactions Fluid mosaic model

Organelles Endoplasmic reticulum (ER) – SER: lipid synthesis – RER: protein synthesis Golgi apparatus: modify, sort, and package proteins Lysosomes: digest food particles Vacuole: contain fluid Endosymbiotic – Mitochondria: convert sugar into ATP – Chloroplasts: photosynthesis Plastids

Cytoskeleton Network of protein fibers to which organelles and cell structures are attached Functions: – Determine the shape of cells – Cell movement – Organelle movement – Chromosome movement and cytokinesis (cell division)

Nucleus Function: store DNA Parts: – Nuclear envelope – Chromatin – Nucleolus

Transport Passive transport: down a concentration gradient, without energy – Simple diffusion – Facilitated diffusion – Osmosis Active transport: against a concentration gradient, needs energy Endocytosis