- 1 For which of the following molecules does chemical digestion begins in the mouth?
- 2 How is the stomach lining protected from the strongly acidic pH of its contents?
- 3 What process breaks down the macronutrients in our food into their building blocks where does this process take place?
- 4 What process of digestion occurs in the mouth?
- 5 What is an example of chemical digestion?
- 6 Which acid is present in our stomach?
- 7 What is the pH of stomach acid?
- 8 What is the formula for stomach acid?
- 9 How food is absorbed into the bloodstream?
- 10 What are examples of macronutrients?
- 11 What is food broken down into?
- 12 What are the 7 steps of digestion?
- 13 What are the 14 parts of the digestive system?
- 14 What are the 6 steps of digestion?
For which of the following molecules does chemical digestion begins in the mouth?
The chemical digestion of starches begins in the mouth and has been reviewed above. In the small intestine, pancreatic amylase does the ‘heavy lifting’ for starch and carbohydrate digestion (Figure 2).
How is the stomach lining protected from the strongly acidic pH of its contents?
How is the stomach lining protected from the strongly acidic pH of its contents? Mucous cells secrete a protective lubricant into the stomach. It releases a hormone called gastrin, which stops gastric juice secretion. Bile neutralizes the acid soon after it enters the stomach.
What process breaks down the macronutrients in our food into their building blocks where does this process take place?
A chemical digestion process called enzymatic hydrolysis can break the bonds holding the molecular ‘building blocks’ within the food together. For example, proteins are broken down into their ‘building block’ amino acids.
What process of digestion occurs in the mouth?
Mechanical digestion in the oral cavity consists of grinding of food into smaller pieces by the teeth, a process called mastication. Chemical digestion in the mouth is minor but consists of salivary amylase (ptyalin, or alpha-amylase) and lingual lipase, both contained in the saliva.
What is an example of chemical digestion?
Chemical digestion breaks down different nutrients, such as proteins, carbohydrates, and fats, into even smaller parts: Fats break down into fatty acids and monoglycerides. Nucleic acids break down into nucleotides. Polysaccharides, or carbohydrate sugars, break down into monosaccharides.
Which acid is present in our stomach?
The hydrochloric acid in the gastric juice breaks down the food and the digestive enzymes split up the proteins. The acidic gastric juice also kills bacteria. The mucus covers the stomach wall with a protective coating.
What is the pH of stomach acid?
The normal volume of the stomach fluid is 20 to 100 mL and the pH is acidic (1.5 to 3.5). These numbers are converted to actual acid production in units of milliequivalents per hour (mEq/hr) in some cases.
What is the formula for stomach acid?
The secretion of bicarbonate from the pancreas is stimulated by secretin. This polypeptide hormone gets activated and secreted from so-called S cells in the mucosa of the duodenum and jejunum when the pH in the duodenum falls below 4.5 to 5.0. The neutralization is described by the equation: HCl + NaHCO3 → NaCl + H2CO.
How food is absorbed into the bloodstream?
As food passes through the GI tract, it mixes with digestive juices, causing large molecules of food to break down into smaller molecules. The body then absorbs these smaller molecules through the walls of the small intestine into the bloodstream, which delivers them to the rest of the body.
What are examples of macronutrients?
Macronutrients: Carbohydrates, Fats and Proteins
- Healthy carbs.
- Healthy protein.
- Good and bad fats.
What is food broken down into?
Along the way, food is broken down into tiny molecules so that the body can absorb nutrients it needs: Protein must be broken down into amino acids. Starches break down into simple sugars. Fats break down into into fatty acids and glycerol.
What are the 7 steps of digestion?
The digestive processes are ingestion, propulsion, mechanical digestion, chemical digestion, absorption, and defecation. Some chemical digestion occurs in the mouth.
What are the 14 parts of the digestive system?
The main organs that make up the digestive system (in order of their function) are the mouth, esophagus, stomach, small intestine, large intestine, rectum and anus. Helping them along the way are the pancreas, gall bladder and liver. Here’s how these organs work together in your digestive system.
What are the 6 steps of digestion?
The six major activities of the digestive system are ingestion, propulsion, mechanical breakdown, chemical digestion, absorption, and elimination. First, food is ingested, chewed, and swallowed. Next, muscular contractions propel it through the alimentary canal and physically break it down into tiny particles.