Human Nutrition and Digestion Quiz

The study of how the body uses nutrients for energy, growth, and regulation at the cell, tissue, and whole-body levels.

They are the building blocks of the human body, comprising 63% oxygen (O), 18% carbon (C), 3% nitrogen (N), and 6% hydrogen (H).

They are carbohydrates, fats (or lipids), and proteins. The body needs large amounts of them for energy and building blocks.

They are vitamins and minerals, essential for various bodily functions, but needed in smaller amounts compared to macronutrients.

These are nutrients our bodies can't produce and must be obtained through our diet.

These are nutrients that our bodies can produce on their own, so we don't need to consume them from our diet.

They are organic compounds composed of carbon, hydrogen, and oxygen in a 1:1 ratio of carbon to water. Starches and sugars are major sources of fuel for the body.

They are fats, oils, and other fat-like substances. They play roles in energy storage, insulation, and protecting organs.

Enzymes secreted by the pancreas that break down proteins into smaller peptides.

The main fat-digesting enzyme produced by the pancreas, working alongside co-lipase.

The first part of the large intestine, connecting to the ileum.

Inflammation of the appendix, often caused by an imbalance in bacteria.

The primary function of the large intestine, involving the absorption of water and electrolytes.

Bacteria residing in the large intestine that contribute to health by producing beneficial substances.

Food components that support the growth and activity of beneficial bacteria in the gut, often found in fiber-rich foods.

Simple sugars that are the basic building blocks of carbohydrates. Examples include glucose, fructose, and galactose.

Polyunsaturated fatty acids (PUFAs) with double bonds at the 12th and 15th carbons from the methyl end are called omega-3 and omega-6 fatty acids. Humans lack the enzymes needed to create these fatty acids, making them essential in our diet.

Proteins are large, complex molecules essential for numerous biological functions, including structural support, antibody production, nutrient transport, and enzyme activity.

Our bodies cannot produce all amino acids; nine are considered essential and must be obtained from our diet. These amino acids are necessary for growth, tissue repair, and various metabolic processes.

Minerals are inorganic substances vital for health, playing roles in various physiological processes. They are classified into macrominerals, required in larger amounts, and microminerals or trace minerals, required in smaller amounts.

Vitamins are organic compounds crucial for various metabolic processes, and they are classified as either water-soluble or fat-soluble. They are essential for a healthy body, but cannot be produced in sufficient amounts by our bodies.

Water is the most basic nutrient, essential for survival. It comprises a significant portion of our body and plays numerous vital roles, including hydration, temperature regulation, nutrient transport, and waste removal.

The mouth is the first stage of digestion, where mechanical breakdown of food begins with chewing. Saliva, containing amylase and lingual lipase, initiates the digestive process.

The stomach is a muscular organ responsible for churning food and mixing it with gastric juice, a combination of hydrochloric acid (HCI) and pepsin, further breaking it down into chyme.

The stomach is protected by a layer of alkaline mucus that safeguards it from the acidic digestive juices and enzymes produced within it.

The process of stomach acid production is stimulated by three factors acting at specific receptors of oxyntic cells: acetylcholine, histamine, and gastrin. All three signals must be present for maximal acid production.

Stomach acid is essential for breaking down food, particularly proteins. It also plays a role in the absorption of iron.

Gastric acid secretion is regulated by three phases: the cephalic, gastric, and intestinal phases. Each phase contributes to the overall production of stomach acid.

The cephalic phase of gastric secretion is triggered by the sight, smell, taste, or even thought of food. This phase contributes about 30% of total acid secretion.

The gastric phase of gastric secretion is triggered by the distension of the stomach and the presence of amino acids and peptides in the stomach. This phase contributes about 60% of total acid secretion.

The intestinal phase of gastric secretion is triggered by the distension of the small intestine and the presence of proteins and their breakdown products. This phase contributes about 10% of total acid secretion.

The small intestine is the primary site of nutrient absorption, receiving chyme from the stomach and mixing it with pancreatic secretions.

The small intestine is folded to increase the surface area for absorption, and has finger-like projections called villi. This structure significantly increases the area available for nutrient uptake.

Microvilli are hair-like structures found on the surface of enterocytes in the small intestine. They further enhance the surface area for absorption, making it even more efficient.

The large intestine is responsible for absorbing water and electrolytes, as well as carrying waste products out of the body.

The liver produces bile, which is stored in the gallbladder and released into the small intestine. Bile helps to emulsify fats, making them easier to digest and absorb.

Bile acids are detergents that break down large fat globules into smaller lipid droplets, enhancing their digestion and absorption.

The gallbladder stores and concentrates bile during periods of fasting. When food enters the duodenum, the gallbladder releases this concentrated bile to aid in fat digestion.

The pancreas releases pancreatic juice into the small intestine. This juice contains bicarbonate, electrolytes, and digestive enzymes, crucial for digestion.

Enterocytes are cells that line the small intestine, constantly being renewed by cells from the crypt. They play a vital role in nutrient absorption and act as a barrier against bacteria.