Nutrition Exam 1

What is Nutrition?

Applied biochemistry and physiology

What is diet formulation?

Application of nutrition and economics

What is nutrient allocation?

What is the most effective way to use a source of nutrients

What are Carbohydrates?

The end product of photosynthesis. CHOs are the base source of energy

What are non-structural carbs?

Sugar and starches (NCHO)

How digestible are non-structural carbs?

Very easy to digest

What are structural carbs?

Fiber, celluose

How digestible are structural carbs?

NOT DIGESTIBLE BY MAMMALIAN ENZYMES

What are proteins?

Macromolecules of Amino Acids (AA). Contains Nitrogen and can be used as a source of energy.

How do the 10 essential amino acids interact with the body?

The EAAs must be absorbed by the small intestine.

How do the 10 non-essential amino acids interact with the body?

NEAAs can be synthesized by a mammal.

What are lipids?

Fats. Soluable in organic solutions.

How many essential fatty acids are there?

TWO

What are minerals?

Rocks; inorganic material. Consists of macrominerals and microminerals

What are our macrominerals? What is it calculated by?

Calcium, Phosphorus, Sodium, Chlorine, Potassium, Magnesium, and Sulfur. This is calculated by percentage.

What are our microminerals? What is it calculated by?

Manganese, Zinc, Iron, Copper, Selenium, Molybdenum, Cobalt, Iodine, and Florine. This is calculated by ppm and ppb.

What are vitamins?

Fat soluable, ADEK, KADE. H2O soluable; daily consumption required.

What should be considered when thinking about water?

Is it clean an abundant? What conditions are animals attempting to drink water in? (Think about environment temp - hot/cold and access)

What are enzymes?

Proteins, biological catalysts, increases the rate (k) of a reaction.

How to enzymes work?

They increase biochemical reactions, by interacting with reactants and products to increase the likelihood of the reaction occuring.

What are proenzymes/zymogens?

Inactive forms of an enzyme, must be activated

What is metabolism?

Sum of biochemical reactions in the body

How does increasing a person’s metabolism affect the rate of biochemical reactions?

Biochemical reactions will also increase.

What is anatolism?

Biosynthesis, building more complex molecules, requires energy

What is catabolism?

Degration of complex molecules into simple molecules. Yields energy

What is Digestive Physiology?

How the animal’s digestine tract is built, diet selection or dietary strategy. Determines an animal’s ability to extract nutrients from a feedstuff.

What are some examples of a monogastric (nonruminants)?

Pigs, Humans, Horses, Cats, Dogs, and Lions

What is autoenzymatic digestion?

Digestion using enzymes made by the mammal

What is alloenzymatic digestion?

Digestion using enzymes of a microbial origin

Does a pig have autoenzymatic or alloenzymatic digestion in their stomach? Small intestine? Large intestine?

Stomach: Auto

Small Instestine: Auto

Large Intestine: Allo (microbes)

Does a horse have autoenzymatic or alloenzymatic digestion in their stomach? Small intestine? Large intestine?

Stomach: Auto

Small Instestine: Auto

Large Intestine: Allo (microbes) - SCHO

What are ruminants?

Animals that have 4 compartments to their stomach

What are some examples of a ruminant?

Cows, Sheep, Goats, Bison, Deer, and Giraffes

What are the 4 compartments of the ruminant digestive system?

Rumen, reticulum, abomasum, and omasum

What do the rumen and reticulum combine into?

Reticubrumen

What does the Reticubrumen do?

Microbial fermentation and alloenzymatic digestion

What is the abomasum also called?

“The true stomach”

What is the abomasum?

The gastric region of the stomach. Has autoenzymatic digestion and a low pH

What is the lumen?

Space inside of the gastrointestinal tract. It goes from the mouth to the anus and is located outside of the body.

Where does digestion occur?

In the lumen

Where does absorption occur?

At the surface of the lumen

What are the main functions of sphinctors?

Slow the flow of digesta, increasing the length of the tract

What does Kp reference?

The rate of passage (how fast the digesta moves)

What does a small Kp mean?

A slow rate of passage

What does a slow rate of passage indicate?

It increases retention time which also increases digestion

What does Kd reference?

The rate of digestion (how fast nutrients are digested)

How do we calculate the extent of digestion?

Kd/ (Kd + Kp) = % of a nutrient absorbed

What does an increase in Kd mean?

An increase in extent of digestion

What does an in Kp mean?

A decrease in extent of digestion

How does the oral cavity (mouth) start digestion?

It starts digestion through mechanical breakdown through mastication (chewing)

What is the main function of mastication?

Decreaseing particle size

What are the benifits of decreasing partical size?

It increases digestion due to an increase in surface area.

What does an increase in surface area lead to?

An increase of enzymatic access

Why is it important for food to mix with saliva?

It is important for lubrication (allows you to swallow food), it allows enzymes start digestion, it is important for buffers and minerals and overall oral health (prevents tooth decay)

What is the definition of the esophagus?

It is a tube that transports food from the outh to the stomach

What are the main functions of the stomach?

• Storage - provides a place to store a meal

• Controls the flow of digesta (food + secretions) to the small intestine (controls Kp)

• Mixing - physical processing

• Produces secretions - enzymes, acid, buffer, and mucus

What does the acid do in the stomach?

The HCl decreases pH. Denatures proteins and kills microbes.

What does the buffer do in the stomach?

HCO3 increases pH. It is close to the stomach surface and mainatins a nutural pH to protect the stomach.

What does the mucus do in the stomach?

It protects the surface of the stomach from acids and enzymes

What is a gastric ulcer?

Damage to the surface of the stomach

What animals are predisposed to gastric ulcers?

Horses, Pigs, and Humans

What are gastric ulcers caused by?

Stress, NSAIDs, and H pylori

How does the stomach digest food?

It does it two ways:

1. Chemical (acid) breakdown through low pH

2. Enzymatic digestion through the activation of zymogens

What components does the stomach absorb?

H2O, alcohol, Cu, Fl, Mo, and aspirin

What is the primary purpose of digestion?

Preparing ingested material for absorption

What is the main purpose of mechanical digestion?

Decrease partical size and increase surface area

What type of reaction is caused by enzymatic digestion?

A hydrolytic reation (Hydrolysis or the insertion of H2O)

What does NCHO break down to? Where does this happen?

NCHO breaks down into monosaccarides in the stomach

What do proteins break down to? Where does this happen?

AA, dipeptides, and tripeptides

What do lipids(fats) break down to? Where does this happen?

Monoacylglyceride + 2 fatty acids

What is absorption?

When a molecule moves from the lumen (outside) into the body - it will typically cross a cell membrane.

What does the pyloric sphincter do?

It controls the flow of digesta into the small intestine

What structure determines Kp?

The pyloric sphincter

What structure allows the stomach to stretch?

The folds of the rugae