Digestion

Question 1

What is the esophagus?

Answer 1

The esophagus is the hollow muscular tube that passes food and liquid from your throat to your stomach. It moves food through slowly, it doesn’t just fall through.

Question 2

What is digestion?

Answer 2

The process of breaking down food, mechanically and enzymatically. This food is broken down into substances that can be absorbed into the bloodstream.

Question 3

What is chemical digestion?

Answer 3

This is the process of breaking down food molecules into their chemical components, so they can be absorbed through the intestinal wall, and into the bloodstream, where the cells can convert it into ATP. The intestinal brush border enzymes and pancreatic enzymes, as well as stomach acids are the ones that do the most chemical digestion. The salivary glands, stomach, small intestine and pancreas do this.

Question 4

What is mechanical digestion?

Answer 4

This is done when you physically break down food into smaller pieces. Teeth, Peristalsis, Liver, Gall Bladder all do this. When it breaks down this food, it increases the surface area of of the food particles, and this allows all the other aspects of digestion to work better.

Question 5

What is the small intestine?

Answer 5

A long tubelike organ that connects the stomach to the large intestine. It has three parts, the duodenum, the jejunum, and the ileum. It breaks down food, absorbs nutrients into the body, and excretes unnecessary components.

Question 6

What does the pancreas do?

Answer 6

It produces enzymes that help to digest food, particularly protein, sugars, fats and starches and it also makes insulin, which is a hormone that controls blood sugar levels. It also stimulates stomach acids and tells your stomach when to empty.

Question 7

How does saliva help with digestion?

Answer 7

It contains special enzymes that help digest the starches in your food. Your upper digestive tract, mouth and esophagus all have salivary glands.

Question 8

How are acids neutralized?

Answer 8

Bicarbonate ions are secreted by the stomach to act as a buffer and decrease the acid content of chyme.

Question 9

How are enzymes used in digestion?

Answer 9

Enzymes are what do chemical digestion, and they help break down your food. Carbohydrases break down carbohydrates into sugars, Lipases break down fats into fatty acids, and Proteases break down protein into amino acids.

Question 10

What is bile?

Answer 10

A fluid that is made and released by the liver, then stored in the gallbladder. Bile helps with digestion; it breaks fat down into fatty acids and contains mostly cholesterol.

Question 11

What is emulsification?

Answer 11

When large lipid globules are broken down into smaller lipid globules. These small globules are distributed in chyme instead of in large chunks. This is done because lipids are hydrophobic and don’t want to dissolve nicely.

Question 12

What is a bolus?

Answer 12

A ball-like mixture of food and saliva that forms in your mouth while chewing. Once it hits the stomach, it starts turning into chyme.

Question 13

What is chyme?

Answer 13

The post-stomach, liquid version of chyme that goes through the intestines. It is very acidic. Feces comes after the chyme’s nutrients have been totally absorbed, leaving only waste.

Question 14

What are macromolecules?

Answer 14

Carbohydrates, lipids, proteins, and nucleic acids.

Question 15

What are lipids?

Answer 15

Also called triglycerides, they are all of the fats and waxes in your body, and they carry the fat-soluble vitamins. They store all energy and are an important structural compound of cell membranes.

Question 16

What are carbohydrates?

Answer 16

Also called poly/di/monosaccharides, these are sugar molecules and carbs. They are turned into glucose, which the body uses for energy. Complex carbohydrates are found in fruits and vegetables and are better for you than simple carbohydrates, aka sugars.

Question 17

What are proteins?

Answer 17

Formed from folding amino acid chains called peptide chains, which are held together by peptide bonds. To absorb amino acids, all of the peptide bonds are broken, allowing you to take in the amino acids. These are used to make muscle and bone, as well as being in enzymes and hormones. They are what build your muscles.

Question 18

What are nucleic acids?

Answer 18

DNA & RNA. They are the biomolecules that store genetic information. You need to consume it so your body can make DNA, and it can be found in anything that is living.

Question 19

What are monomers?

Answer 19

Monosaccharides are the monomers of carbohydrates, amino acids are the monomers of proteins, glycerol/fatty acids are the monomers of lipids, and nucleotides are the monomers of DNA. A monomer is any molecule that can be bonded to identical molecules to form a polymer.

Question 20

What are sugars?

Answer 20

These are carbohydrates called monosaccharides. They are the simplest form of carbohydrates and are easily absorbed in the intestine. The three main ones we consume are glucose, fructose and galactose, which form into lactose and sucrose, which are disaccharides.

Question 21

What do the tails on carbohydrates show?

Answer 21

Cellulose, which is a dietary fibre we cannot digest, has alternating “tails”. Digestible carbs have non-alternating “tails”.

Question 22

What are fatty acids?

Answer 22

The building blocks of the fat in our bodies and the food we eat. They are absorbed into the blood during digestion and used to form cell membranes. They also store our energy.

Question 23

What are unsaturated fatty acids?

Answer 23

There are unsaturated fatty acids, which have some double bonds in them, and are healthier for you as they help remove some cholesterol.

Question 24

What are saturated fatty acids?

Answer 24

Saturated fatty acids have hydrocarbon chains connected by single bonds and are less healthy and raise your cholesterol.

Question 25

What is glycerol?

Answer 25

Glycerol is a small, organic molecule with three hydroxyl (OH) groups. All fat molecules have a glycerol backbone and three fatty acid “tails”. They are the base of fat molecules.

Question 26

What are amino acids?

Answer 26

The molecules that combine to form proteins. They form them by making peptide chains, which fold to form proteins. They are the building blocks of life.

Question 27

What do vitamins do?

Answer 27

Vitamins allow enzymes to work, which make us grow and develop correctly, also function correctly, they are important to how cells work.

Question 28

What do ions do?

Answer 28

They affect the distribution of water throughout your body and regulate the flow of water into your cells.

Question 29

What is fibre/cellulose?

Answer 29

It is a fibre found in plants; it isn't digestible and helps food move through the digestive tract more easily.

Question 30

What is the Biuret test for?

Answer 30

This tests for proteins. It starts blue and turns purple if a protein is detected. Biuret = Blue!

Question 31

What is the Iodine test for?

Answer 31

This test is for starches and complex sugars. It begins brown and turns black when it interacts with starches or sugars.

Question 32

What is the paper bag/emulsification test for?

Answer 32

This tests for lipids. If lipids get on the paper bag, it will look wet from the grease. In an emulsification test, they will form a gross cloudy suspension.

Question 33

What is Benedict's test for?

Answer 33

This tests for simple sugars. It is blue, and turns orange/brick red when it interacts with simple sugars.

Question 34

What are carbohydrase enzymes?

Answer 34

Enzymes capable of hydrolyzing complex carbohydrates into simple sugars. Made in the stomach, small intestine and the pancreas. Nutrients (glucose) produced are absorbed into the bloodstream. Amylase is one of these.

Question 35

What are amylase enzymes?

Answer 35

Changes starches into simple sugars during digestion. Made mostly in the salivary glands and the pancreas. Nutrients (glucose) produced are absorbed into the bloodstream.

Question 36

What are lipase enzymes?

Answer 36

A type of digestive enzyme that helps break down fats so they can be absorbed in the intestine. It is mostly made in the pancreas, and a little bit in the salvatory glands, and the stomach. The nutrients (fatty acids, glycerol) produced are absorbed into the lymphatic system.

Question 37

What are protease enzymes?

Answer 37

Break down proteins in the body by adding a water molecule, hydrolases. They are made in the pancreas. Nutrients (amino acids) produced are absorbed into the bloodstream. Pepsin is one of these. There is also endopeptidase, an enzyme that breaks down peptide bonds other than the terminal ones on the peptide chain, meaning the bonds within the molecule, not the end pieces.

Question 38

What are pepsin enzymes?

Answer 38

Digests proteins found in indigested food. They are made in the stomach. Nutrients (amino acids) produced are absorbed into the bloodstream. Protein pumps move them, using ATP.

Question 39

What is absorption?

Answer 39

The stomach and both intestines absorb nutrients in your food into the blood so they can be used in the body. The small intestines do most of this.

Question 40

What is diffusion?

Answer 40

When digested nutrients pass into the blood vessels in the wall of the intestine, it is through diffusion. The inner wall of the small intestine is covered in mucosa, which allows for diffusion.

Question 41

What is active transport with sodium and potassium?

Answer 41

This is the transport of sodium out of the cell and potassium into the cell through sodium-potassium pumps. It takes place in the internal lining of the small intestine.

Question 42

What is a substrate?

Answer 42

A substance used to make a product, the raw material that acts with enzymes to speed up the reactions that turn them into products. Co-factors and co-enzymes are also called co-substrates.

Question 43

What are co-factors?

Answer 43

A non-protein chemical compound that is bound to an enzyme and is required for the enzyme’s biological activity. They are also called helper molecules. They are required for enzyme activity; they just help.

Question 44

What are co-enzymes?

Answer 44

Substances that help enzymes do their jobs. They alter the active site of the enzyme; they are not proteins. They are needed for enzyme activity for specific substrates.

Question 45

What is a catabolic reaction?

Answer 45

This is when large organic molecules are broken down into smaller molecules, which releases the energy contained in their chemical bonds. A single substrate molecule will be drawn to the active site of an enzyme and broken down into smaller parts.

Question 46

What is a hydrolysis reaction?

Answer 46

This is a type of catabolic reaction where a larger molecule is broken down into two smaller ones, and water is consumed as a reactant.

Question 47

What are anabolic reactions?

Answer 47

This is when large molecules are synthesized from smaller molecules using ATP. This builds new proteins, muscle mass, fats, and nucleic acids. Simple substrates are drawn into the active site, and bonds are formed to make them into a single molecule.

Question 48

What is a dehydration synthesis reaction?

Answer 48

This is an anabolic reaction where two or more substrates/molecules are joined together to form a larger molecule in a reaction that produces water. This means the enzyme joins the substrates together into one, and the water is a byproduct of the reaction.

Question 49

What is glycogen?

Answer 49

This is the stored form of glucose that is made up of many connected glucose molecules. Glucose is the body’s main form of energy. It is stored in the skeletal muscles and the liver.

Question 50

What is adipose tissue?

Answer 50

Also known as fat, this is the loose, connective tissue that is made of mainly adipocytes.

Question 51

What does it mean when an enzyme denatures?

Answer 51

This is when an enzyme is overheated or exposed to the incorrect pH. This damages or kills the enzyme, and it loses its shape and structure, meaning it will no longer function properly. Temperature and pH need to be at certain levels for enzymes to work, and if they are not at those levels, then the enzymes will be denatured.

Question 52

What is competitive inhibition?

Answer 52

This is when there is competition for the active site of an enzyme by an interfering agent. It can be temporary or permanent, and it prevents the enzyme from doing its job, as substrate molecules cannot bind to its active site. The inhibitor molecule will compete with substrate molecules.

Question 53

What is non-competitive inhibition?

Answer 53

This is when a substance that doesn't resemble the substrate attaches itself to a chemical site that isn't the active site, which then rearranges the enzyme, making it useless. The site it binds to is called the allosteric site. When something binds to the allosteric site, it changes the shape of the enzyme's active site, making it so none of the normal substrates can bind to the active site.

Question 54

What is feedback inhibition?

Answer 54

This is a series of reactions that leads to the synthesis of a product. When enough of this product is formed, it will connect to the allosteric sites of the enzymes at the start of the sequence, stopping them from making any more of this product until the body needs more of it.

Question 55

What is an intermediate in enzymes?

Answer 55

It is when the product formed from the reaction of one enzyme is the substrate for a different enzyme.

Question 56

What is an allosteric site?

Answer 56

This is a place for substrates or other things to bond to an enzyme, but it is located off to the side of the enzyme. It is often a place for non-competitive inhibitors.

Question 57

What is an active site?

Answer 57

This is the main place on enzymes where substrates bind to make the enzymes go through reactions.