Chapter 3 - Lecture notes 3 PDF

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Differentiated cells: cells with specialized characteristics ● Form from less specialized cells that divide and express specific genes Three major parts of a cell: ● Nucleus ○ Innermost ○ Enclosed by a thin membrane called the nuclear envelope ○ Contains DNA ● Cytoplasm ○ Includes specialized structures called cytoplasmic organelles that are suspended in a liquid called cytosol ● Cell membrane ○ Allows the cell to receive and respond to incoming messages, in a process called signal transduction ○ Has cholesterol and protein in the wall so it doesn’t slip around Eukaryotic: cells with nuclei (humans) ● "true nucleus" Prokaryotic: cells without nucleus (bacteria) ● "before nucleus" The basic framework of the cell membrane is a double layer, or bilayer, of phospholipid molecules that self-assemble Molecules soluble in lipids, such as oxygen, CO2, and steroid hormones, can pass through the phospholipid bilayer ● However, the bilayer is imperviable to water-soluble molecules, such as amino acids, sugars, proteins, nucleic acids...