Hardened deposits of cholesterol that accumulate in the structure that stores bile are known as

A. baked fresh fish

B. lettuce-and-tomato salad

C. fried chicken breast

D. milkshake

B) lettuce-and-tomato salad

- Correct: Lettuce-and-tomato salad would provide the most roughage for the body. Roughage, also known as dietary fiber or bulk, refers to the indigestible portion of plant foods that adds bulk to the stool and helps regulate bowel movements. Lettuce and tomatoes are both rich sources of dietary fiber. Lettuce, especially varieties like romaine or leaf lettuce, contains cellulose and other insoluble fibers, while tomatoes contain soluble fibers like pectin. Consuming a salad made of lettuce and tomatoes would provide a significant amount of roughage to the body, promoting digestive health and regular bowel movements.

A) baked fresh fish

- Incorrect: Fish does not contain significant amounts of dietary fiber. While fish is a valuable source of protein and other nutrients, it is not a source of roughage.

C) fried chicken breast

- Incorrect: Fried chicken breast does not contain significant amounts of dietary fiber. Additionally, frying can add unhealthy fats and calories to the chicken breast, further reducing its nutritional value in terms of roughage.

D) milkshake

- Incorrect: Milkshakes are typically made with milk, ice cream, and flavorings, none of which provide dietary fiber. In fact, milkshakes are generally low in fiber and may contain high amounts of sugar and fat, making them poor choices for increasing roughage intake.

A. ulcers

B. appendicitis

C. diarrhea

D. constipation

D) constipation

- Correct: Feces with reduced water content, such as reducing the water content to 20 percent, would result in constipation. Constipation refers to infrequent bowel movements or difficulty passing stool, often characterized by hard, dry, and difficult-to-pass stools. When feces have less water content, they become harder and drier, making them more difficult to pass through the intestines. This can lead to discomfort, straining during bowel movements, and a sense of incomplete evacuation.

A) ulcers

- Incorrect: Ulcers are sores or lesions that develop in the lining of the digestive tract, commonly in the stomach or the upper part of the small intestine. They are not directly related to changes in the water content of feces.

B) appendicitis

- Incorrect: Appendicitis is inflammation of the appendix, a small pouch located near the junction of the small and large intestines. It is not directly related to changes in the water content of feces.

C) diarrhea

- Incorrect: Diarrhea refers to frequent, loose, or watery bowel movements. Reduced water content in feces would lead to constipation rather than diarrhea.

A. saturated lipids

B. complete proteins

C. complex carbohydrates

D. nucleic acids

C) complex carbohydrates

- Correct: Complex carbohydrates, such as whole grains, legumes, fruits, and vegetables, are sources of roughage in the human diet. Roughage, also known as dietary fiber, refers to the indigestible portion of plant foods that adds bulk to the stool and promotes healthy digestion. Complex carbohydrates contain both soluble and insoluble fiber, which helps regulate bowel movements, prevent constipation, and promote overall digestive health.

A) saturated lipids

- Incorrect: Saturated lipids, commonly found in animal fats and some plant oils, are not sources of roughage. While they are a component of the diet and provide energy, they do not contribute to the fiber content of the diet.

B) complete proteins

- Incorrect: Complete proteins, which contain all essential amino acids, are not sources of roughage. Proteins are important for building and repairing tissues, as well as for various physiological functions, but they do not provide dietary fiber.

D) nucleic acids

- Incorrect: Nucleic acids, such as DNA and RNA, are not sources of roughage. They are essential molecules involved in genetic information transfer and protein synthesis but are not related to the fiber content of the diet.

A. emulsification

B. manufacturing more bile

C. converting glycogen into glucose

D. releasing iron

C) converting glycogen into glucose

- Correct: When no carbohydrate ingestion occurs in the body during a 24-hour period, the liver can provide for the body's glucose needs by converting stored glycogen into glucose through a process known as glycogenolysis. Glycogen is a polysaccharide that serves as a storage form of glucose in the liver and muscles. When blood glucose levels decrease, such as during fasting or low carbohydrate intake, the liver breaks down glycogen into glucose molecules, which are then released into the bloodstream to maintain blood glucose levels and provide energy to cells throughout the body.

A) emulsification

- Incorrect: Emulsification is a process by which bile breaks down large fat globules into smaller droplets to aid in fat digestion in the small intestine. It is not related to the liver's role in glucose metabolism.

B) manufacturing more bile

- Incorrect: The liver produces bile continuously, regardless of carbohydrate ingestion. While the liver's production of bile is important for fat digestion and absorption, it is not directly related to glucose metabolism.

D) releasing iron

- Incorrect: The liver is involved in storing and regulating iron levels in the body, but releasing iron is not directly related to providing for the body's glucose needs in the absence of carbohydrate ingestion.

A. The action of enzymes varies with pH.

B. A pH of 7 provides the optimum environment for digestive enzymes.

C. Gastric juice is active at a pH extending from 0 to 12.

D. Acids have a pH greater than 7.

The action of enzymes vary with pH. Enzymes are proteins that catalyze biochemical reactions, and their activity is influenced by various factors including pH.

The pH level affects the ionization state of amino acid residues within the enzyme's active site. This, in turn, can affect the enzyme's ability to bind substrate molecules and catalyze reactions.

Different enzymes have different optimal pH ranges at which they exhibit maximum activity. This optimal pH range is determined by the specific environment in which the enzyme typically functions. For example, pepsin, which is involved in digesting proteins in the stomach, works optimally at an acidic pH around 2, whereas enzymes in the small intestine function optimally at a slightly alkaline pH around 7 to 8.

Extreme deviations from the optimal pH can denature enzymes, causing them to lose their structure and function. Therefore, maintaining the appropriate pH level is crucial for ensuring the proper functioning of enzymes in biochemical reactions.

A. predators

B. pathogenic organisms

C. parasitic fungi

D. decomposers

B) pathogenic organisms

- Correct: Salmonella bacteria are pathogenic organisms, meaning they can cause disease in humans and other animals. When ingested, Salmonella bacteria can lead to symptoms such as stomach cramps, vomiting, diarrhea, and fever. Salmonella infection, known as salmonellosis, is a common cause of foodborne illness, often associated with the consumption of contaminated food, particularly undercooked poultry, eggs, and unpasteurized dairy products.

A) predators

- Incorrect: Predators are organisms that hunt, kill, and consume other organisms for food. Salmonella bacteria are not predators; they do not actively hunt and consume other organisms.

C) parasitic fungi

- Incorrect: Salmonella bacteria are not parasitic fungi. Parasitic fungi are fungi that derive nutrients from living organisms, often causing harm or disease. Salmonella bacteria are a distinct type of pathogenic bacteria, not fungi.

D) decomposers

- Incorrect: Decomposers are organisms that break down and feed on dead organic matter, aiding in the process of decomposition. Salmonella bacteria are not decomposers; they are pathogenic bacteria that can cause illness in humans and animals.

A. coenzymes

B. auxins

C. hormones

D. neurotransmitters

A) coenzymes

- Correct: Some vitamins function as coenzymes, which are molecules that assist enzymes in their catalytic activity. Coenzymes work together with enzymes to facilitate various biochemical reactions in the body. For example, certain B vitamins (such as thiamine, riboflavin, and niacin) act as coenzymes in energy metabolism, while vitamin K acts as a coenzyme in blood clotting. Without these essential vitamins, many metabolic processes in the body would be impaired, leading to various health problems.

B) auxins

- Incorrect: Auxins are plant hormones that regulate plant growth and development. They are not vitamins and do not function as coenzymes in biochemical reactions in organisms.

C) hormones

- Incorrect: Hormones are signaling molecules that regulate various physiological processes in organisms. While some vitamins may indirectly influence hormone production or function, they do not function primarily as hormones themselves.

D) neurotransmitters

- Incorrect: Neurotransmitters are chemical messengers that transmit signals between nerve cells (neurons) in the nervous system. They are not vitamins and do not function as coenzymes in biochemical reactions in organisms.

A. F

B. G

C. C

D. D

Most reabsorption of water occurs in the large intestine, F.

A. stomach

B. gall bladder

C. villi

D. lacteals

B) gall bladder

- Correct: Bile, which aids in the emulsification of fats in the small intestine, is stored and concentrated in the gall bladder before being released into the small intestine. When fatty foods enter the small intestine, the gall bladder contracts and releases bile into the duodenum (the first part of the small intestine). Bile helps to break down large fat globules into smaller droplets, a process known as emulsification, which increases the surface area for the action of digestive enzymes, such as lipase, facilitating the digestion and absorption of fats.

A) stomach

- Incorrect: Bile is not released from the stomach. The stomach primarily secretes gastric juices containing hydrochloric acid and pepsinogen to aid in the digestion of proteins.

C) villi

- Incorrect: Villi are finger-like projections in the lining of the small intestine that increase its surface area for nutrient absorption but do not release bile.

D) lacteals

- Incorrect: Lacteals are lymphatic vessels found in the villi of the small intestine that absorb dietary fats and fat-soluble vitamins. They do not release bile.

A. Specific enzymes break down proteins into amino acids.

B. Specific hormones break down proteins into simple sugars.

C. Specific hormones break down proteins into complex starches.

D. Specific enzymes break down proteins into simple sugars.

A) Specific enzymes break down proteins into amino acids.

- Correct: This is the correct answer. Proteins are broken down into their constituent amino acids by specific enzymes during the process of digestion. Enzymes like pepsin in the stomach and various proteases in the small intestine facilitate this breakdown.

B) Specific hormones break down proteins into simple sugars.

- Incorrect: Hormones are not directly involved in breaking down proteins into simple sugars. Hormones are signaling molecules that regulate various processes in the body, including metabolism, but they don't directly participate in the breakdown of proteins into sugars.

C) Specific hormones break down proteins into complex starches.

- Incorrect: Hormones do not break down proteins into complex starches. Proteins are broken down into amino acids by enzymes, not hormones. Starches are complex carbohydrates and are broken down into simple sugars by enzymes like amylase, not proteins.

D) Specific enzymes break down proteins into simple sugars.

- Incorrect: Proteins are not broken down into simple sugars. They are broken down into amino acids by specific enzymes. Simple sugars come from the breakdown of carbohydrates, not proteins.