A & P II Final Exam From Test #2

The circulation route that runs from the digestive tract to the liver is called hepatic portal circulation. This circulation system allows nutrients and other substances absorbed from the digestive tract to be transported directly to the liver for processing and detoxification before entering the general circulation. The hepatic portal vein carries blood from the intestines, stomach, and spleen to the liver, where it is filtered and metabolized before being distributed to the rest of the body. This specialized circulation route helps maintain the balance of nutrients and toxins in the body.

Capillaries are the smallest blood vessels in the body and their primary function is to permit the exchange of nutrients and gases between the blood and tissue cells. These thin-walled vessels have a large surface area, allowing for efficient diffusion of oxygen, carbon dioxide, and other molecules between the bloodstream and surrounding tissues. Arterioles, arteries, and veins are also involved in the circulation of blood, but they do not have the same level of permeability and direct interaction with tissue cells as capillaries do.

The normal number of permanent teeth in a human is 32. This includes 8 incisors, 4 canines, 8 premolars, and 12 molars (including 4 wisdom teeth). These teeth typically start to erupt around the age of 6 and continue until the late teenage years or early adulthood.

When we ingest large molecules such as lipids, carbohydrates, and proteins, they must undergo catabolic reactions whereby enzymes split these molecules. This series of reactions is called chemical digestion.

Arteries are blood vessels that carry oxygenated blood away from the heart to various parts of the body. They have thick, muscular walls that help maintain the blood pressure and ensure efficient blood flow. Arteries do not carry oxygenated blood to the heart; instead, veins are responsible for returning deoxygenated blood back to the heart. While some arteries do contain valves, their main function is to regulate blood flow rather than prevent backflow. Additionally, all arteries, regardless of their size, are lined with endothelium, a thin layer of cells that helps reduce friction and promote smooth blood flow.

Chemical digestion refers to the breakdown of large complex molecules into simpler compounds. This process is known as catabolism, which involves the breaking down of substances to release energy. Mastication, on the other hand, is the physical process of chewing food. Anabolism is the opposite of catabolism, as it involves the building up of complex molecules from simpler ones. Fermentation is a metabolic process that occurs in the absence of oxygen. Therefore, the correct answer is catabolism.

Emotional state is not one of the three main factors influencing blood pressure. Blood pressure is primarily influenced by cardiac output, which is the amount of blood pumped by the heart per minute, peripheral resistance, which is the resistance to blood flow in the arteries, and blood volume, which is the total volume of blood in the body. Emotional state can temporarily affect blood pressure through the release of stress hormones, but it is not a main factor.

The hepatic portal circulation is responsible for collecting absorbed nutrients from the gastrointestinal tract and delivering them to the liver for metabolic processing or storage. This allows the liver to regulate nutrient levels in the body and ensure that they are used efficiently for energy production or stored for later use.

The stomach initiates protein digestion and denatures proteins. This is because the stomach produces hydrochloric acid and enzymes like pepsin, which break down proteins into smaller peptides. Additionally, the low pH in the stomach denatures proteins, unfolding their structure and making them more accessible to digestive enzymes. The stomach is not the first site where absorption takes place, as most absorption occurs in the small intestine. It is also not the only place where absorption takes place, as some absorption can occur in the stomach and other parts of the digestive system. The stomach is not the first site where chemical digestion of starch takes place, as the breakdown of starch begins in the mouth with the enzyme amylase.

When the environmental temperature rises, blood flow to the skin increases. This is because the body needs to cool down in order to maintain its normal temperature. By increasing blood flow to the skin, heat can be transferred from the body to the skin surface, where it can be dissipated through sweating and radiation. This helps to regulate body temperature and prevent overheating.

Deciduous teeth, also known as baby teeth or primary teeth, are the first set of teeth that erupt in a child's mouth. These teeth start to appear around 6 months of age and are usually fully developed by the age of 2 to 3 years. The normal number of deciduous teeth is 20, with 10 teeth in the upper jaw and 10 teeth in the lower jaw. These teeth eventually fall out and are replaced by permanent teeth as the child grows.

Saliva is a fluid produced by the salivary glands in the mouth. It helps in various functions such as cleansing the mouth, moistening the food, aiding in the compaction of the bolus, and dissolving food chemicals for taste. However, saliva does not contain enzymes that begin to breakdown proteins. The breakdown of proteins primarily occurs in the stomach with the help of enzymes like pepsin.