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The digestive system breaks down food into:

A. nutrients

B. amylase

C. saliva

D. sphincters

Answer Explanation:

a. nutrients

- Correct: The digestive system breaks down food into nutrients. These nutrients include carbohydrates, proteins, fats, vitamins, minerals, and water, which are essential for various physiological functions in the body. Once broken down into nutrients through mechanical and chemical digestion, these substances are absorbed by the intestines and transported via the bloodstream to cells throughout the body for energy production, growth, repair, and other metabolic processes.

b. amylase

- Incorrect: Amylase is an enzyme involved in the digestion of carbohydrates. It is produced by salivary glands in the mouth and by the pancreas and helps break down complex carbohydrates into simpler sugars. While amylase is an important component of the digestive process, it is not the end product of digestion.

c. saliva

- Incorrect: Saliva is a fluid secreted by salivary glands in the mouth. It contains water, electrolytes, mucus, and enzymes such as amylase. Saliva helps moisten food, initiate the digestion of carbohydrates, and facilitate swallowing, but it is not the end product of digestion.

d. sphincters

- Incorrect: Sphincters are ring-like muscles that control the movement of materials through various parts of the digestive tract by opening and closing. While sphincters play a crucial role in regulating the flow of food and waste through the digestive system, they are not the end products of digestion.

 

Therefore, the Correct Answer is A.

More Questions on TEAS 7 Science

  • Q #1: Chemical digestion of carbohydrates begins in the

    A. esophagus

    B. stomach

    C. duodenum

    D. oral cavity

    Answer Explanation

    D. oral cavity

    - Correct: Chemical digestion of carbohydrates begins in the oral cavity. Salivary glands in the mouth secrete saliva, which contains an enzyme called amylase. Amylase breaks down complex carbohydrates (such as starch) into simpler sugars (such as maltose) through hydrolysis. This process initiates the digestion of carbohydrates before the food bolus reaches the stomach or small intestine.

    A. esophagus

    - Incorrect: The esophagus is primarily involved in the propulsion of food from the mouth to the stomach through peristaltic contractions. It does not play a significant role in the chemical digestion of carbohydrates.

    B. stomach

    - Incorrect: While the stomach plays a role in the digestion of proteins through the action of gastric juices containing pepsin and hydrochloric acid, it does not contribute significantly to the digestion of carbohydrates. In fact, the acidic environment of the stomach may temporarily inhibit the activity of salivary amylase.

    C. duodenum

    - Incorrect: The duodenum is the first part of the small intestine where the majority of chemical digestion occurs. While the duodenum receives pancreatic enzymes and bile that aid in the digestion of carbohydrates, proteins, and fats, the initial chemical digestion of carbohydrates primarily occurs in the oral cavity with the action of salivary amylase.

  • Q #2: Which part of the large intestine attaches to the appendix?

    A. cecum

    B. ascending colon

    C. transverse colon

    D. descending colon

    Answer Explanation

    Cecum attaches to the appendix

  • Q #3: Which of these ingredients in saliva is responsible for activating salivary amylase?

    A. mucus

    B. phosphate ions

    C. chloride ions

    D. urea

    Answer Explanation

    b) phosphate ions

    - Correct: Phosphate ions are responsible for activating salivary amylase. Saliva contains salivary amylase (also known as alpha-amylase or ptyalin), which is an enzyme that catalyzes the hydrolysis of starch into maltose and other smaller carbohydrates. However, salivary amylase is only activated in the presence of certain ions, particularly phosphate ions. These ions help to stabilize the enzyme's structure and facilitate its enzymatic activity. Therefore, phosphate ions play a crucial role in the function of salivary amylase.

    a) Mucus

    - Incorrect: Mucus in saliva serves primarily as a lubricant and protective barrier for the oral mucosa and facilitates swallowing. It does not directly activate salivary amylase

    c) Chloride ions

    - Incorrect: Chloride ions are electrolytes present in saliva, but they do not directly activate salivary amylase. Instead, they help maintain the osmotic balance and pH of saliva.

    d) Urea

    - Incorrect: Urea is a waste product found in urine and is not directly involved in the activation of salivary amylase.