Option D.1 To D.3

Question 1

What causes malnutrition

Answer 1

By a deficiency, imbalance or excess of nutrients in diet

Question 2

Are amino acids essential?

Answer 2

9 out of 20 are (these cannot be synthesized by the body)
4 are not essential so the body can produce these
And the rest are conditionally essential, can be produced in small amount under certain conditions

Question 3

What is PKU?

Answer 3

Genetic condition that mutates the phenylalanine hydroxylase enzyme. When our body ingests phenylalanine it breaks it down using that enzyme. But if a person has PKU that enzyme does not function properly resulting to a toxic buildup of phenylalanine in the blood and urine which can lead to brain damage for example.

Question 4

How is PKU treated?

Answer 4

By a strict diet that limits the intake of the amino acid phenylalanine

Question 5

Name some essential fatty acids

Answer 5

Omega 3 and omega 6
Bc we lack proper enzymes
Found in fish and walnuts

Question 6

Can fat molecules and cholesterol be broken down in the bloodstream? If not how does the body mange either

Answer 6

No.
Packages them into lipoproteins structures that can be transported.

High density lipoproteins also known as HDL carry excess cholesterol back to the liver for disposal, lowering blood cholesterol levels. (Good)

Low density lipoproteins also knows as LDL carry cholesterol from the liver to the body, which raises blood cholesterol levels. (Bad)

Question 7

How do fats affect HDL and LDL levels

Answer 7

Consuming fats affects both HDL and LDL levels
However saturated and trans fats increase LDL levels

Question 8

What can a build up of LDL in the bloodstream create

Answer 8

They can build up and create plaques that block blood flow, which can lead to a heart attack if this occurs in a coronary artery

Question 9

Are vitamins essential

Answer 9

Most are like vitamins C and D.

Question 10

What can a vitamin c deficiency lead to?

Answer 10

Scurvy. Loosened teeth and bleeding gums. Weakens immune system

Question 11

What does a vitamin D deficiency cause

Answer 11

Vitamin d is involved in the absorption of calcium and phosphorus in the body both of which contribute to bone formation.

Called Rickets, leaving bone weak and misshaped from improper development.

Question 12

What are dietary minerals

Answer 12

Essential chemicals elements such as H, Na, Mg, K, Ca, etc.

Question 13

What are hormones

Answer 13

Chemical messengers thar control many processes

Question 14

How is appetite controlled

Answer 14

the hypothalamus receives signals from lepton or ghrelin which inform the body to feel hungry or full.

Leptin lowers hunger levels, when food has been consumed

Ghrelin increases hunger levels when the body needs food

Question 15

What are the affects of obesity and starvation on the body?

Answer 15

Obesity: type 2 diabetes and coronary heart disease which includes hypertension (high blood pressure)
Both caused by high intake of saturated fatty acids

Starvation: can lead to organ damage and death if calorie intake is not restored fast enough, as the body begins to breakdown down muscles and lipids to generate energy and amino acids. This is known as catabolysis
Anorexia: lack of appetite or restriction of appetite, irrational fear of food.
Can also lead to vitamin deficiency that can cause anämisch vitamin B12 deficiency.

Question 16

What are exocrine glands? structure and function

Answer 16

Exocrine glands secrete to the surface of the body or the lumen of the gut

generic structure:
Composed of secretory cells thar create and secrete chemicals
Duct that allows chemicals to move to desired location

The exocrine glands that secrete digestive juices are controlled by nervous and hormonal mechanisms

Question 17

What are the 4 glands that aid in digestion?

Answer 17

Salivary glands
Gastric glands
Pancreatic glands
And intestinal glands

Question 18

What are nervous and hormonal mechanisms? Give example

Answer 18

Nerves- electrical messages via neurons
Example: smelling food which triggers immediate neural response to secrete the stomach to secret gastric juices, known as pre digestion

Hormones- chemical messages via molecules
Examples: when food enters small intestine the pancreas secrets digestive chemicals like bicarbonate ions and bile that work to neutralize stomach acids and break down fats

Question 19

Why is the stomach acidic?

Answer 19

Gastric glands in the stomach secrete an acidic solution (H+) which creates a low ph environment that digests food, activate stomach proteases and destroys potential pathogens.

Question 20

What are PPI’s?

Answer 20

Proton pumps inhibitors which irreversibly block proton pumps in stomach from secreting H+ ions in stomach to reduce stomach acidity.

Question 21

What are stomach ulcers? How?

Answer 21

Inflamed and damaged area in the stomach wall due to a bacterial infection by helicobacter pylori.
Cells lining the stomach produce a protective mucous layer that prevents the low ph from damaging its own tissue.

H pylori enters the stomach and anchors itself to the lining of the stomach it damages the cell responsible for creating the mucous layer.

The exposure to the low ph, eats away the tissue and causes an ulcer

Question 22

What can our body not digest and Abosrbed?

Answer 22

Fiber.

Question 23

What has consuming high fiber foods shown?

Answer 23

Decrease the rate at which materials move through the digestive system which gives other material other than fiber, obvi, more time to be mixed with enzymes to be digested and also spreads the absorption out by a matter of hours.

All of this is healthy.

Question 24

What and how is cholera caused?

Answer 24

By bacteria called Vibrio cholorea which affects the intestine and causes diarrhea and dehydration.

The bacteria enters the body and secretes a cholera toxin, which once in an epithelial cell increases the rate of cyclic amp, which activate specific ion channels letting ions out of the membrane.

This creates a hypertonic solution on the outside of the membrane and so water is forced to move out by osmosis causing diarrhea and dehydration

Question 25

What is the function of the liver?

Answer 25

Regulates the chemical composition of the blood.
Such as vitamins, sugar (glucose)

Question 26

How does the liver remove toxins from the blood?

Answer 26

Detoxification of the liver:

1. Toxins such as drugs, alcohol, tylenol (fat soluble) are taken in by liver and does a reduction oxidation reaction and hydrolysis (breaking toxins down)
2. Then conjugation which combines them with other molecules to be more easily flushed away
3. They’ll be removed from your body via feces as bile or as urine.

Question 27

How are components of red blood cells recycled?

Answer 27

RBC use hemoglobin to transport oxygen throughout the body.

1.Dead RBC are engulfed by Kupfer cells in the liver by phagocytosis and the RBC are moved inside a vacuole into the cytoplasm. (Spleens also have macrophages that can engulf dead RBC)

2. lysosomes fuse with vacuoles to release enzymes to breakdown the hemoglobin into the Heme group (primary iron and bilirubin) and the globin (an amino acid)
3. The iron is transported to your bone marrow, where RBC are made
4. The bilirubin secreted into bile which will be used in the emulsification of fats.
5. Globin is reused.

Question 28

How are bile salts synthesized and what is its function?

Answer 28

To emulsify fats (breakdown fats into smaller droplets to increase their surface area which allows enzymes to work better)

Synthesized in the liver from a surplus of cholesterol.

Question 29

How are plasma proteins created?

Answer 29

By endoplasmic reticulum and Golgi apparatus in hepatocytes

Hepatocytes have a lot of ribosomes attached to their ER and also have lots of Golgi apparatus, which indicates a high protein synthesis

They produce blood proteins albumin which are the carrier protein thar binds to bilirubin. As well as fibrinogen which is a protein involved in blood clotting

Question 30

The liver intercepts blood from the gut to regulate nutrient levels. Outline which nutrients and how

Answer 30

Most of glucose is absorbed and stored as glycogen, until the body requires energy and so it converts it back to glucose

Fatty acids are absorbed and metabolized to produce energy in the form of ATP.

(Hepatocytes can also synthesize lips such as triglycerides, cholesterol which are bound to proteins forming lipoproteins, that are now soluble in blood and can be transported in blood to all the body)

Amino acids are transformed into other amino acids or used in protein synthesis (such as plasma proteins)
However when the amino acids are no longer needed, hepatocytes remove the amine group (transformed into ammonia, and quickly into urea as NH3 is toxic) from the acid group (used to produce energy or new glucose molecules)

Also toxins aka detoxification.

Question 31

What nutrients are stored in the liver when in excess?

Answer 31

Glucose as glycogen
Iron
Vitamin A and D

Question 32

What are the causes and symptoms of jaundice? Why would a new born have jaundice? Treatment?

Answer 32

Caused by a build up of bilirubin in blood and skin. Liver cannot process and get rid of bilirubin (liver malfunction)

Symptoms: yellowing of eyes and skin

Newborn: liver is not ready to process bilirubin, high turnover of RBC (using lots of RBC so high production of bilirubi), bilirubin is reabsorbed by the gut due to inadequate feeding

Treatment: UV light or putting baby under sunlight, which will break down the bilirubin. An adult would

Question 33

How is blood supplied to and from the liver?

Answer 33

1. Hepatic portal vein carries blood containing digested food from intestine into liver
2. Hepatic artery brings the oxygenated blood to the liver (give oxygen to liver)
3. Hepatic vein carries blood from the liver to the heart with levels of food adjusted.