Almost all the chemical reactions that take place within cells are catalyzed by enzymes. Enzymes are biological catalytic proteins that lower the activation energy needed to start a chemical reaction and, as a result, greatly increase the rate of the reaction. The structure of an enzyme is based on the interaction and bonding of amino acids that make up the protein. There are thousands of different enzymes in a cell, and they are structurally diverse. The structure of the enzyme determines the chemical reaction that it will catalyze. How does DNA impact the function of enzymes?

answer; the tunica intima also called tunica interna, consists of elastic fibers,connective tissue and smooth muscle cells;

interphase

the period of cell growth when the cell synthesizes new molecules and organelles. the cell is not dividing and it constitutes the majority of the time spent in the cell cycle

prophase

changes occur in the nucleus and cytoplasm. the chromatin condenses to form structures (sister chromatids) visible with a light microscope and the mitotic spindle begins to form, but the nucleus is still in tact

prometaphase

the nuclear envelope fragments and the spindle microtubules attach to the kinetochores of the sister chromatids

metaphase

all the cell's duplicated chromosomes are lined up at an imaginary plane equidistant between the poles of the mitotic spindle

anaphase

begins when sister chromatids separate from each other and ending when a complete set of daughter chromosomes arrives at each of the two poles of the cell

telophase

the daughter nuclei form at the two poles of a cell

cytokinesis

the division of a cytoplasm to form two separate daughter cells. usually occurs during telophase during mitosis. this and mitosis make up to mitotic (m) phase of the cell cycle