Week 6 Gastrointestinal :)

The small intestine's primary role is absorption, which refers to the process of taking in nutrients from the digested food and transferring them into the bloodstream for distribution to the body's cells. The small intestine is specifically designed for efficient absorption due to its large surface area, which is increased by the presence of numerous tiny finger-like projections called villi. These villi are lined with microvilli, further enhancing the absorption capacity. Through this process, the small intestine plays a crucial role in ensuring that essential nutrients such as carbohydrates, proteins, fats, vitamins, and minerals are absorbed and utilized by the body.

Salivary amylase is an enzyme that is responsible for breaking down starch. It starts the process of digestion in the mouth by breaking down the complex starch molecules into simpler sugars like glucose. This breakdown continues until the food reaches the upper part of the stomach, where the acidic environment stops the action of salivary amylase. Therefore, the correct answer is starch.

The correct answer is "Water is not being absorbed and secretion exceeds absorption." This mechanism suggests that there is a failure of water absorption in the intestines, leading to an increase in the amount of water in the stool. At the same time, there is an excessive secretion of water into the intestines, further contributing to the diarrhea. This imbalance between absorption and secretion results in the passage of watery stools.

Crohn's disease is a chronic inflammatory condition that can affect any part of the gastrointestinal (GI) tract, although it most commonly affects the terminal ileum. It is not characterized by a blockage or rupture specifically, but rather by inflammation. The inflammation can cause a range of symptoms such as abdominal pain, diarrhea, and weight loss. Treatment for Crohn's disease aims to reduce inflammation and manage symptoms.

The main solutes of the GI tract are sodium, chloride, and bicarbonate. These solutes play important roles in the digestive process. Sodium and chloride are involved in the absorption of water and nutrients, while bicarbonate helps to neutralize stomach acid and maintain the pH balance in the intestines. Together, these solutes contribute to the proper functioning of the GI tract and the overall digestion and absorption of food.

Vitamin B12 is responsible for the formation of erythrocytes, also known as red blood cells. Erythrocytes play a crucial role in transporting oxygen to the body's tissues and removing carbon dioxide. Vitamin B12 is necessary for the production of healthy red blood cells and the prevention of anemia. Without sufficient levels of vitamin B12, the body may not be able to produce an adequate number of red blood cells, leading to fatigue, weakness, and other symptoms of anemia.

Pepsin is an enzyme that helps in the digestion of proteins. It is initially secreted as an inactive form called pepsinogen. Chief cells in the stomach lining are responsible for secreting pepsinogen. When pepsinogen comes into contact with the acidic environment of the stomach, it is converted into its active form, pepsin, which can then break down proteins. Therefore, the correct answer is Chief cells.

The body of the stomach contains glands that secrete pepsinogen, which is the inactive form of pepsin, intrinsic factor, mucus, and hydrochloric acid (HCl). Pepsinogen is later activated to pepsin, which helps in the digestion of proteins. Intrinsic factor is important for the absorption of vitamin B12. Mucus helps to protect the stomach lining from the acidic environment, and HCl helps in the breakdown of food and kills bacteria.

The rhythmic chewing motions of the mouth are activated by the pressure of food against the gum and hard palate. When food is placed in the mouth, it exerts pressure on the gums and the hard palate, triggering the chewing reflex. This reflex involves the coordinated movement of the jaw muscles, allowing the food to be broken down into smaller, more manageable pieces for swallowing and digestion.

Absorption of conjugated bile salts occurs in the terminal ileum. The terminal ileum is the last part of the small intestine before it connects to the large intestine. Bile salts are produced by the liver and stored in the gallbladder. They are released into the small intestine to aid in the digestion and absorption of dietary fats. In the terminal ileum, these bile salts are reabsorbed back into the bloodstream and returned to the liver for recycling. This process is important for maintaining the body's bile salt pool and ensuring efficient fat digestion and absorption.

Nutrient absorption occurs at the apical end of the villus. The apical end refers to the top or outermost part of the villus, which is in direct contact with the intestinal lumen. This is where the microvilli, which are tiny finger-like projections, are located. The microvilli greatly increase the surface area of the villus, allowing for efficient absorption of nutrients from the digested food.