Nutrition - Chapter 6 - Proteins- Dr. Riggins

What makes protein different from each other and from carbohydrates and fats?

R group Nitrogen

What is the only difference on each amino acid that leads to such versatility?

R-group

___ do not exist in nature and so aren't handled by the body as well as whole proteins. Excesses of one amino acid may cause decreased absorption of another and could lead to toxicity.

Single amino acids

An ___ is created from amino acids broken down from proteins in the cells and also from the diet.

amino acid pool

Step 2) The mRNA is translated into a sequence of _____. Amino acids are carried to the mRNA strand by _____ molecules.

amino acids TRN

After deamination, the liver combines the ammonia with ___ to make urea. This is much less toxic and has less of an effect on the blood's pH than ammonia. The liver cells then release the ___ into the blood stream where it will travel to the kidneys and be excreted in the urine.

carbon dioxide urea

Step 1) a gene is transcribed into ______. This then is sent out of the cell to a ribosome.

messenger RNA

One ounce of protein food usually supplies significant protein other than meat is ___.

milk

Structural Material: building blocks of _____,____, and _____.

muscle, blood, skin

Proteins have ___ charges on their surfaces and attract the positive charges on the hydrogen ions.

negative

Amino acids can be used to make compounds other than proteins. ___ such as norepinephrine and epinephrine are examples.

neurotransmitters

The name "amino" comes from the _____ that is added with the carbon, hydrogen, and oxygen in an amino acid.

nitrogen atom

Amino acids can be used to make ___ or other ___. They can also be stripped of their nitrogen and used for ___.

body protein nitrogen-continuing compounds energy

Carbohydrates and fats are stored in the body's cells, but protein aren't. When the body needs protein for energy, it has to ____

break down its working and structional proteins and uses amino acids for energy or glucose.

Each gene codes for a

protein

The consequences of ___ include slowed growth, impaired brain function, obesity, kidney function, poor immunity, and inadequate nutrient absorption.

protein deficiency

The continual formation and break down of proteins is known as ___.

protein turnover

Hormones: While some hormones are made from the lipid cholesterol, some are made from ___.

proteins

Proteins accept and release the hydrogen ions, acting as ___. When the pH goes to low, it is called ___. When the pH is too high, it is called ___. Either one can lead to coma and death.

buffers, acidosis, alkalosis

Describe protein roles in the following:

BLOOD CLOTTING: protein fibrin creates blood clots. VISION: protein opsin participates in vision SCAR FORMATION: protein collagen forms scars

When protein intake is high, ___ excretion increases leading to possible bone loss.

calcium

Crystals of ___,___,___, and ___ are then added to the matrix.

calcium, phosphorus, magnesium, fluoride

____ proteins are ones that can be eaten together to ensure that all essential amino acids are taken in. Vegetarians should take advantage of this practice.

Complementary

How many amino acids are there?

20

How many genes are there estimated to be in the body?

25,000

How many structures are proteins organized in and name them.

4 primary-20 different amino acids chain. secondary-alpha helix weak electrical attractions due to close amino acid bonding tertiary-dydrophilic side groups are on the outer surface near water; hydrophobic groups tuck themselves away from water (tangled structured) quaternary-interaction between two or more polypeptides

How many essential amino acids must be taken in through the diet?

9

___ may be beneficial in cases of liver disease, but otherwise are not recommended because they may lead to raised plasma ammonia concentrations causing toxicity to the brain.

Branched chained amino acid supplement

What is Kwashiorkor

First child is breast fed until second child is born, then 2nd child is breast fed and the first child is fed watery cereal with no nutrition. acute, sever malnutrition characterized by failure to grow and develop, edema, changes in the pigmentation of hair and skin, fatty liver, anemia and apathy. acute, loss of appetite, edema, muscle wasting, fatty damaged liver, free iron promotes infection.

Protein In Foods: ___ provide enough of the essential amino acids needed to support the body's work. Two factors affect the quality of a protein: ___ and ___.

High quality protein digestibility and amino acid composition

Stomach

Hydrochloric acid denatures protein strands and activates pepsin. This enzyme cleaves proteins into smaller polypeptides and amino acids.

Only 2 amino acids have been suggested that may have beneficial health effects:

Lysin - prevent or relieve the infections that cause herpes cold sores on the mouth or genital organs Tryptophan - relieves depression and insomnia

_____ is when nitrogen intake equals nitrogen output. Protein input from food equals nitrogen excretion in urine, feces, and sweat.

Nitrogen balance

Small Intestine

PROTEASES/PEPTIDASE hydrolyze the polypeptides further into tripeptides, dipeptides, and amino acids. Once inside the intestinal cells, amino acids can be used for energy or to synthesize compound if needed. Amino acids that are not used are transported into the capillaries and sent to the liver.

____, used to make color of eyes, skin, and hair and ____ which helps to regulate metabolic balance are other examples. Finally, the precursor of the vitamin ___ and serotonin (sleep regulation, appetite control) is also an amino acid. The amino acid ___ is used to formulate these compounds.

Pigment melanin hormone thyroxine nyecin trypthapan

___ can provide amino acids to the body, but nature's sources - meat, eggs, poultry, and legumes - supply all of them and more.

Protein powder

Amino acid supplements are not as effective as advertised! Why?

The body does not recognized single amino acids. It only deals with whole proteins.

Nitrogen status can become positive if the body synthesizes more than degrades.

True

How long are most proteins?

a few dozen to several hundred amino acids long

Protein provides ___ when added to a meal, keeping a person feeling full for longer.

adequate energy

Difference between essential, nonessensial, condition and limiting amino acids

amino acids that the body requires but can not make and so must be obtained from the diet, also called indispensable amino acids. amino acids that the body can make, also called dispensable amino acid. an amino acid that is normally nonessential, but must be supplied by the diet in special circumstances when the need for it exceeds the body's ability to make it. the essential amino acid found in the shortest supply relative to the amounts needed for protein synthesis in the body. Four amino acids are most likely to be limiting lysine, methionine, threonine, and tryptophan

An error in the sequence of amino acids results in

an error in protein

Proteins from ___ tend to be high quality proteins. Proteins from plants tend to be limiting in some amino acid, so they are ___. Corn is especially low in quality while soy is especially high.

animals plants

Antibodies: Each antibody is designed to attack a specific ____. When that same one comes into the body again, it remembers how to make those antibodies and quickly sends them out to defeat the invader. This molecular memory is known as ___.

antigen immunity

Enzymes- break down, build up, and transform one substance to another. Breaking down reactions are called ___, and building up reactions are called ___.

catabolic, anabolic

To build bone or tooth, a matrix of _____ (a protein) is first lain down.

collagen

Proteins are also used for replacing

dead or damaged cells

To break down amino acids, they must first be ___, which means to remove the nitrogen-containing amino group. This leaves two products: ___ & the rest.

deaminated ammonia

Heat, acid, or other conditions can make a protein unstable, what is this called?

denaturation

What does 2 amino acids bonded together form? 3? Many?

dipeptide tripeptide polypeptide

List a few jobs that proteins do in the body:

everything, build structural material, muscle contraction & building, blood clotting, blood, skin, hair, antibodies, energy, eyes to see

Proteins is foods become body proteins directly.

false, DNA makes protein in the body.

Protein rich foods can contribute to weight gain because protein can be converted to ___.

fat

What else is changed if the structure of a protein is changed?

function

_____ is the creation of protein in the amounts and at the rate the cell needs, but each cell has the entire set of genes. Ex: the pancreas expresses genes for _______, but those genes are idle in other cells. The diet plays a major role in gene expression.

gene expression insulin

A Source of Energy and Glucose: When glucose levels are low, the body will pull from tissue proteins to make amino acids available for energy or glucose production, a process called ___.

gluconeogenesis

What is the simplest amino acid?

glycine

___ protein diets have been implicated in heart disease, cancer, osteoporosis, obesity, and kidney stones.

high

Digestibility of animal proteins is ____, while digestibility of plant proteins is ____.

high 90 to 99% less 70 to 90%

The greater the concentration of ____, the more acidic the solution, and the ____ the pH.

hydrogen ions, lower

Regulators of Fluid Balance Proteins are usually found ______ and in the ______. Since they are large, they usually don't cross the walls of the blood vessels.

in the cells, plasma

Acid - Base Regulators Normally, when acids and bases are produced during body processes, they are sent to the ___ & ___ for excretion.

kidney, lungs

Collagen also provides material of ___ and ___ and the "glue" between artery cells that allows them to withstand blood pressure. Scars are also made with collagen.

ligaments, tendons

The body makes whole proteins only, so if an amino acid is missing, the body won't make the protein. An essential amino acid missing from the diet is ___.

limiting amino acid

Disease of the liver and kidney can be diagnosed because of these processes. If blood ammonia is high, then a person may have ___. If blood urea is high, the person may have ___.

liver disease kidney disease

What are more than half of the amino acids considered?

nonessential

The protein RDA for adults is ___. It is slightly higher in infants and children.

o.8g

Transporters: Hemoglobin carries ___, lipoproteins carry ___, and special transproters carry ___ and ___.

oxygen, lipids, vitamins, minerals

List a few hormones made from protein and their functions.

oxytocin & prolactin - support lactation, growth hormone - promote growth, insulin & glucagon - regulate blood glucose, thyroxin - reg. body's metabolic rate, calcitonin & parathyroid hormones - reg blood calcium, angiotensin, renin, antidurectic hormone - reg fluid & electrolyte balance

What do amino acids form when bonding together?

peptide bonds

What is Marasmus

severe malnutrition characterized by poor growth, dramatic weight loss, loss of body fat and muscle, and apathy: chronic, loss of fat, irritable, appetite is strong, skin sags, layers of pigment in skin and hair changes, impairs brain development, growth ceases, body temp is down, metabolism slows, diarrhea, fatigue, shock, flaky rash

Why is the simplest amino acid glycine?

side chain is only hydrogen

Amino acids, because of their unique side chains, all differ in what?

size, shape, electrical charge

During illness, liver disease or protein malnutrition though, the proteins in the plasma will leak out of the blood vessels and into the ________.

space between the cells

Each enzyme facilitates a ___ reaction. Ex: enzymes cannot help each other out. Each one does its own job.

specific

Each transport protein is ___. Some act as pumps and require energy. Ex: the sodium-potassium pump. A high concentration of ___ and a low concentration of ___ must be maintained in the cell. If this pump doesn't work correctly and these concentrations change, irregular heartbeat, muscular weakness, kidney failure and death can occur.

specific potassium, sodium

What is nonessential?

the body will make amino acids as long as there is nitrogen and fragments of carbohydrates and lipids.

How are peptide bonds formed?

through condensation reactions

What reaction occurs to allow the liver to synthesize the nonessential acids.

transamination

REMEMBER: A change in pH can denature proteins!!

true

Without protein arteries are weak and will leak.

true

While high protein diets have been implicated in heart disease, substituting ___ for animal protein may improve blood pressure and blood lipids. ___ is an amino acid that may specifically be related to heart disease.

vegetable Homocysteine

A person on a high-protein diet must drink a lot of ___ because the body will use it to excrete the urea. If it isn't taken in, the body will pull it from other areas of the body causing dehydration. This also explains how high-protein diets seem to be effective. Tremendous water loss does show up on the scale.

water

Proteins attract _____ to this area causing swelling. Swelling due to fluid in the tissues is called ____. Edema causes diminished capacity to ___________________________________.

water, edema, deliver nutrients and oxygen to the cells and to remove waters from them

What is a conditional essential amino acid?

when an essential amino acid is used to make a nonessential one.

Can a nonessential amino acid become an essential amino acid?

yes