AP BIOLOGY

Detailed explanation-1: -The fundamental building blocks of all cell membranes are phospholipids, which are amphipathic molecules, consisting of two hydrophobic fatty acid chains linked to a phosphate-containing hydrophilic head group (see Figure 2.7).

Detailed explanation-2: -Cell membranes are composed of proteins and lipids. Since they are made up of mostly lipids, only certain substances can move through. Phospholipids are the most abundant type of lipid found in the membrane. Phospholipids are made up of two layers, the outer and inner layers.

Detailed explanation-3: -Phospholipids are major membrane lipids that consist of lipid bilayers. This basic cellular structure acts as a barrier to protect the cell against various environmental insults and more importantly, enables multiple cellular processes to occur in subcellular compartments.

Detailed explanation-4: -Answer and Explanation: The cell structure that is made mostly of phospholipids is the cell membrane. The cell membrane contains two layers of phospholipids oriented in a manner where the tails of the fatty acids are tucked in the middle, and the polar head groups are oriented to the periphery of the membrane.

Detailed explanation-5: -In general, phospholipids are composed of a phosphate group, two alcohols, and one or two fatty acids. On one end of the molecule are the phosphate group and one alcohol; this end is polar, i.e., has an electric charge, and is attracted to water (hydrophilic).