Ribosomes manufacture proteins, the smooth endoplasmic reticulum transports materials within the cells, the rough endoplasmic reticulum transports ribosomes which are made in the nucleolus to other parts of the cell, and the cytoplasm is the living material that cushions the cell and allows chemical reactions to occur.

There are two fundamental sections of the cell cycle: mitosis and interphase. The M phase denotes mitosis, during which the cell divides. Interphase is composed of several subsections during which the cell grows, organelles replicate, and the cell prepares for division.

Interphase can be divided into the subsections G1, S, and G2. While G1 and G2 are dedicated to the growth of the cell and organelle replication, the S phase is when cellular DNA is replicated.

Passive transport processes move ions or molecules across the plasmalemma without any energy expenditure by the cell whereas active transport processes involve the cell spending energy.

During diffusion a molecule moves from an area of high concentration to an area of low concentration. Movement is achieved following the concentration gradient and no energy is spent by cell.

Receptor-mediated endocytosis is a process that resembles pinocytosis but is far more selective and only allows the entry of specific molecules into the cell. Target substances are bound to receptors on the membrane surface and brought into the cell via coated vesicles.

A cell does not have to have a nucleus. Prokaryotic cells are characterized by the fact that they don't have a nucleus nor any other membrane-bound organelles. However the rest of the statements are true of all cells and comprise cell theory.

Bacterial cells have cell membranes, cell walls, chromosomes, cytoplasm, and ribosomes. They may have flagella or cilia as well. They do not contain any membrane-bound organelles, such as the nucleus, endoplasmic reticulum, or mitochondria.

RNA and DNA have many similarities in structure. They are both nucleic acids, meaning they are polymers of nucleotides; the structure of both DNA and RNA is made by bonding many nucleotide units into a long polymer chain. These chains are created by bonding in the sugar phosphate backbone. Each nucleotide contains a sugar, a phosphate, and a nitrogenous base. When the sugars and phosphates bind, nucleotides are strung together to create the nucleic acid chain.

There are two key structural differences between DNA and RNA. The first is the identity of the sugar used in the sugar phosphate backbone. DNA uses deoxyribose, while RNA uses ribose. Both are pentose sugars, meaning they have five carbons, but the 2' carbon in RNA has a hydroxyl group that is absent in DNA. The second major difference is the identity of the nitrogenous bases used to code genetic information. DNA uses cytosine, guanine, adenine, and thymine. RNA uses cytosine, guanine, adenine, and uracil. Thymine will not be found in RNA and uracil will not be found in DNA.

DNA replication is defined as being semiconservative. This statement means that when a DNA molecule undergoes replication, the DNA helix unwinds and each strand serves as a template for the new strand to be created. Once a new DNA molecule has been created, it is composed of both an old strand (template), and the newly created strand, thus making a new double helix.

While the answer choice about leading and lagging strands is a true statement with regard to DNA replication, it is unrelated to the semiconservative nature of the process.

During DNA replication, DNA polymerase III needs a site of attachment in order to begin DNA strand synthesis. This template is provided by primase, which lays down an RNA primer for DNA polymerase III to attach.

RNA polymerase is not involved in DNA replication (it is involved in translation), and DNA polymerase I is used to replace the RNA primers with DNA nucleotides.

Proteins have a variety of functions in the body, one of which is acting as biological catalysts. These specialized proteins are called enzymes and are used to facilitate all types of chemical reactions in organisms.

Storing genetic information is accomplished by nucleic acids, and energy is provided by carbohydrates. Lipids (or phospholipids to be specific) help create the plasma membrane structure.