أسئلة وأجابتها 1

Why is the term "dehydrogenation" appropriate؟

 saturated fat is converted to

an unsaturated fat

 

In the structure of fats enters oxygen, hydrogen and carbon atoms.They are the main sources of fatty acids and they have a vital role in maintaining healthy skin and hair, in protecting the body from shock, temperature maintenance and normal functioning of cells. Fats are synthesized in the body to form glycogen and fatty acids. Glycogen can be converted into glucose by the liver and used as energy source. Fatty acids provides energy, especially to heart and muscle tissue.

Fats are classified by their origin: animal fats (usually solid - saturated) and vegetal fats (usually liquid, oil - unsaturated) and after the nature of fatty acids that predominate in the composition of glycerides. Thus saturated acids generate solid fats and unsaturated acids generate liquid fat.

Vegetable fats have double bonds between carbon atoms of the "tail" (not in all atoms). This connection does not allow their union by a large number of hydrogen atoms and therefore are called unsaturated.

Addition of hydrogen to molecules of unsaturated organic substances has many applications in industry, being used to transform liquid fats into solid fats.

A hydrogenation reaction affecting the food industry is the hydrogenation of vegetable or animal fats, liquids, in order to obtain solid (from oil is obtained margarine). The catalyst used is nickel. Hydrogenated fat resembles with the natural one
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Question on amino acids?

Amino acids such as valine, leucine, isoleucine and phenyl alanine are often found in the interior of water soluble proteins, while arginine, lysine and aspartic acid are often found on the surface. Explain this observation. Where would you expect to find alanine and glutamic acid in this protein. Relate your answer to the structure of the amino acids.

Alanine can exist in 3 forms: two enantiomers and an optically inactive substance. The combined state is found in various proteins such as casein, gelatin, especially silk proteine.Beta Alanine is found in nature as a component of pantothenic acid, which is a Vitamin from B complex, representing one of the growth factors. This is the only beta-amino acid existent in nature.

Asparagic acid and glutamic acid were obtained first by hydrolysis of mono-amides. Glutamic acid can be obtained by synthesis, too. Both acids have important role in protein metabolism. Asparagic acid has a similar position in the formation of amino acids in plants.

Albumins are the most common proteins. They are particularly prevalent in the animal kingdom, are found in blood serum (serum albumin), in egg whites (egg albumin), milk, etc.. Albumins are met in vegetable proteins, although to a lesser extent, for example, wheat seeds (leucosina) or ricin (castor).Proteins are easily soluble in water and diluted solutions of electrolytes, by heating ,coagulates the solution, they contain more glutamic acid, in solution have most neutral reaction.

What 4 atoms do protein molecules always contain? What other atoms might they contain?

1.

amarang9 Teacher

eNotes Editor

Protein molecules always contain Carbon, Oxygen, Hydrogen and Nitrogen. Occasionally, they will contain Sulphur - such as Cysteine, Methionine, and Cystine. A Phosphate (Phosphurus) is also used in other derivations and biosyntheses: Glutamate-5-Phosphate is produced when Proline is synthesized from Glutamate. A Carbamoyl-Phosphate is used in the Urea Cycle: a process which converts toxic Ammonia into urea or uric acid so the organism can more easily process and utilize Nitrogen (N) without the build up of Ammonia (NH3) during protein digestion.

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Are the following Proteins, Carbohydrates, lipids, or Nucleic Acids?

1.)repairs tissue

2.)provides energy for all of life processes

3.)made up pf amino acids

4.)concentrated, stored energy source

5.)simple ones are the sugars

6.)contains info of how to build proteins

7.)complex ones include starch and cellulose

8.)complex ones include steroids and vitamins

9.)two types are RNA & DNA

10.)what extra sugars are turned into

11.)simple ones includes butter, wax, & oils

12.)is found only in the nucleus of a cell

13.)builds new tissue & makes up enzymes

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Why do alcoholics suffer from a lack of essential fatty acids (Omega 3)?

From what I have been able to discover, the reason why alcoholics suffer from a lack of essential fatty acids is mainly because of their dietary choices. When a person consumes large amounts of calorie-rich alcohol they acquire fewer calories from traditional, varied sources. In short, when people are "getting their beer on" they don't tend to eat with an eye toward nutrition. This leads to all sorts of problems, not just with fatty acids, but with all of the bodies nutritional needs.

To a lesser extent, alchohol also increases the rate at which fats are broken down.

At any rate, alcoholics (or those who just drink a lot) benefit, health wise, from supplements that replace these nutrients.

Explain how information is transferred through DNA on chromosomes when cells divide.

 

The Central Dogma of genetics--that is, how the information needed to construct all the proteins for cells--is that DNA is transcribed into RNA, which is translated to proteins. If those words sound like words used in reading a foreign language, it is because that is kind of what is happening. DNA is made up of four types of nitrogenous bases: adenine, guanine, thymine, and cytosine. They are strung in a chain, that makes up DNA. After the DNA is "unzipped" so that it is a single strand instead of a double strand, the DNA is copied by a strand of RNA; only one type of base will attach to the corresponding DNA base. Cytosine attaches to guanine, and adenine, instead of attaching to thymine like it would in a complimentary DNA strand, is instead attached to uracil in RNA. The RNA bases are then "read" in sets of three; each set of three codes for a specific amino acid. The amino acid sequence that results is the specific type of protein coded for by the original strand of DNA.

How is dopamine involved in addiction?

Dopamine is a neutrotransmitter -- a kind of chemical that transmits information from neuron to neuron.

When a person takes some kinds of addictive drugs, like cocaine or heroin, the drugs affect the way that dopamine is produced or the way that it is taken up. In either case, the use of the drugs causes there to be excess dopamine levels in the body.

This is important because the body appears to use dopamine to alert itself as to what is important. It surges when we are hungry and smell food and it surges when we sense danger. If dopamine levels are increased by drug use, the increased dopamine levels tell us we need the drug.

Thus, dopamine production is at the base of the biological process of addiction.

Identify and explain what could go wrong if your blood pH goes below, 7.0. And, what could go wrong if your blood pH were to increase above 7.8.

The ideal pH for blood is from 7.3 - 7.4, or slightly alkaline. The body has several mechanisms for regulating blood pH. If blood pH is too low (which is typical, as most of what we eat is acidic) the body introduces minerals (particuarly potassium, sodium, magnesium, and calcium) to buffer the blood. If your diet contains enough of these minerals, all is well; if not, the body leaches them from wherever it can - particularly from your bones and muscles.

If the blood pH is low, early symptoms may include skin eruptions, headaches, allergies, cold- and flu-like symptoms, and sinus problems. If the blood pH remains low, orgains such as thyroid glands, adrenal glands, and the liver may begin to fail. Low blood pH decreases oxygen levels in the blood, slowing or even stopping cellular metabolism. Ultimately, this could lead to death.

The blood can become too alkaline as well (from lack of acidic foods, ingesting alkaline products such as antacids), resulting in alkalosis. Symptoms include dizziness and lightheadedness, and (like acidosis) decrease in oxygen levels in the blood
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What is the difference between respiration and photosynthesis?

Respiration is a process by which animals take oxygen from their environments required for converting food in to energy and release the carbon dioxide generated in this process to the environment.Photosynthesis is a process by which plant convert light energy in to chemical energy and store as food.

We can identify three major differences between respiration and photosynthesis. These are:

1. Respiration occurs in animals while photosynthesis occurs in plants.

2. Respiration involves absorbing oxygen from the environment and releasing carbon dioxide in it. The reverse happens in the process of photosynthesis. Carbon dioxide is absorbed from the environment and oxygen is released.

3. Respiration is part of process that converts food or chemical energy to heat or work energy. Photosynthesis is the process of producing food by converting light energy to chemical energy.

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Expalin Cell Mediated Immune System?

Cell mediated immunity is where something foreign (unless it is an autoimmunte disease) is recognized by cells in the immune system which results in the invader being destroyed. There is a complex interaction between T (thymus) cells, B (lymphocyte) cells and the different factors given off by them which determines how it is handled. Generally T cells "eat" the foreign substance and create different factor signals it then either releases into the bloodstream or carries on the cell surface. The B cells respond to those signals to either destroy the foreigner immediately, or surround it so it can't cause harm and "escort" it though the lymph system so it can be excreted. Any basic immunology textbook describes this process in excrutiating detail and lists the known factors and how they interact between the T and B cells
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What are some of the differences between DNA and RNA?

DNA or Deoxyribonucleic acid is the nucleic acid which contains all the genetic instructions for the functioning of all living organisms.

RNA or Ribonucleic acid is also a nucleic acid which functions as a carrier of genetic information and a catalyst of biochemical reactions.

Some of the important differences are as follows:

1. Structurally the DNA is a double stranded molecule with a long chain of nucleotides while the RNA is a single stranded molecule with a shorter chain of nucleotides.

2. DNA is found in the nucleus while RNA is found in the nucleus and the cytoplasm.

3. Deoxyribose sugar in DNA is less reactive because of C-H bonds. Ribose sugar in RNA is more reactive because of C-OH (hydroxyl bonds).

4. DNA is stable in alkaline conditions, while RNA is not stable in alkaline conditions.

5. The helix geometry of DNA is of B-form while the helix geometry of RNA is of A-form.

6. The DNA is completely protected by the body while RNA strands are continually made, broken down and reused.

7. DNA can be damaged by exposure to ultra violet rays, while RNA is more resistant to damage by ultra violet rays
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Describe the journey of a starch molecule in a piece of bread as it passes through the gut?

Carbohydrates (carbon hydrates) are molecules composed of carbon, hydrogen and oxygen and they form the basis of our food. They deliver the main energy reserve of the body. Glucose is the main fuel of the physical body,and it is stored as glycogen in muscle and liver.

It is found in foods that originally contain either natural sugar (fruit, honey) or starch (cereals, potatoes, etc.). Acid starch associations are incompatible

Reasons:

1. Starch digestion begins in the mouth under the effect of salivary enzymes which acts only in alkaline environment.The presence of an acid in the mouth at the same time (vinegar, lemon, etc.) slows down or even make disappear enzyme action;

2. Unchanged starch in the mouth then rots in the stomach;

3. Such starch, once reached the stomach can not be prepared to subsequent action of pancreatic amylase ;

4. Acid digestion of food consumes more energy, same starch digestion, leading to depleting reserves allocated for digestion;

5. acid-starch digestion times are different (fruits digest faster and the starch and much harder). Their association disrupt digestion times.

Meals that contain starchy foods should be placed at least 30 minutes after ingestion of acidic foods such as: yogurt, kefir, fruit acids.

Should be avoided completely use of vinegar or lemon juice to salads which are consumed together with starch! Weak concentrated starch-protein association is incompatible

Reasons:

1. salivary digestion of starch is in the alkaline environment, stomach digestion of proteins is in basic environment;

2. starch digestion in the small intestine is done in almost neutral environment unlike that of proteins.

Weak concentrates protein: milk, yogurt, cheese degreased.

Example of random nefarious: croissants (much starch in flour) with milk, can cause severe indigestion. Fat concentrated starch-protein association is semi-compatible

Reasons:

1. proteins remain longer in the stomach;

2. starch-protein association of fat inhibits secretion of gastric acid juice, positive to protein digestion ;

3. pancreas takes over the digestion of proteins and it gets tired.

Fats concentrated proteins are : butter, oil, cheese, egg yolk, nuts, olives, nuts.

Starch-rich sugars carbohydrates association is incompatible. Reasons:

1. sugar inhibit salivary secretion enzyme necessary to digest starch;

2. two types of carbohydrates digest in different segments of the digestive tract (stomach, small bowel respectively);

3. gastrointestinal fermentation is created, the source of stomach burns.

Sample all incompatible foods: cake (starch in flour, cream and sugar syrup, butter cream).

Example of random nefarious starch-sugar: mashed potatoes sweetened.

Starch-lipid association is incompatible

Reasons:

1. consume energy reserves needed for digestion because there are two types of digestion in different segments of the digestive tract;

2. Free deposits of body fat: carbohydrate (starch) is transformed into glucose, the pancreas secretes insulin. Part of fat energy, which normally would have been evacuated, turn into this reserve of fat on insulin;

3. favors cellulite and obesity.

Sample disastrous food: potatoes (starch) fried (fats become evil because they are heat processed).

Example of completely poisonous Association: steak and fries with fat (Fried Cheese).

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Are complex carbs fat or water soluble?

 

Complex carbohydrates are long chains of sugar molecules (polysaccharides) that are not quickly broken down by the body into glucose (a monosaccharide). Complex carbs are not fat soluble. Items that are considered complex carbohydrates contain whole grain or whole fruit items rather than refined starch, white sugar, or high fructose (monosaccharide) corn syrup.

Complex carbohydrates contain more than one sugar molecule which gives them the name complex or the prefix poly- before saccharide (sugar).

. State whether blood plasma is a good buffer or not.

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2. What is the effect of HCl on standard buffer solution?

what is the effect of acid on standard buffer solution.

 

 

 

Blood plasma is a weak buffer. Remember that it is designed to buffer around pH 7.4 and therefore its capabilities are limited to weak acids or alkalis. For example, carbon dioxide dissolved in it forms a weak acid, which plasma can buffer. Plasma would not be able to buffer strong mineral acids.....it was never designed for that purpose! The effect of acid on a standard buffer solution depends on the strength of the acid. A standard buffer will more easily cope with a 1 mM solution of HCl than a 1 M solution of the acid. Mineral acids (HCl H2SO4 and HNO3) will require higher buffering than weaker acids eg. acetic acid
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I understand that water cannot be magnetized. Can lymph fluid?

 

Yes, but it isn't easy. By that I mean, the worn out red blood cells being carried by the lymph system will have some iron in them. Therefore, you could magnetize them without manipulating them on a minute level. However, more aggressive manipulation of the white blood cells can be done; iron-heavy proteins can be inserted into the body, which can be taken up by the white blood cells. This allows scientists to track them via MRI, and would make magnetizing them possible. So, you can magnetize some of the components of the lymph
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What is the name and the length of the shortest protein in the human body?

 

 

Human protein Q6YH21, a collagen-like molecule associated with acetylcholinesterase in skeletal muscle, has a variant gene NM_080542, which encodes for the shortest protein in the human body. See more detailed information, including the gene sequence, at the link:

Sources:

http://www.ncbi.nlm.nih.gov/entrez/viewer.fcgi?tool=porta...

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How do green algae absorb CO2 and H2O...since it's nonvascular?

As I understand it, CO2 and H2O are absorbed through diffusion directly through the cell membrane in green algae. (and almost all other cells)

CO2 can diffuse directly through the lipid-bilayer of the cell membrane. As the concentration of CO2 in the cell becomes less then the surrounding air/water, the CO2 in the surrounding air/water diffuses down its concentration gradient into the cell. One reason for a lowering concentration of CO2 could be that it is being used in the Calvin cycle of photosynthesis.

Water also diffuses into the cell, but it cannot pass directly through the lipid-bilayer. Water diffuses through membrane bound proteins. Also, the diffusion of water is given a more specific name, Osmosis. Osmosis is a little bit diffrent then diffusion because water is the solvent for most solutes in the cell. (fats are not water soluble)

Hope i answered your question! :) (hope its the right answer too...)

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green algae absorb co2 through active transport with the aid of the enzyme called carbonic anyhydrase
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Biology -
 What is the general use of hormone replacement therapy in people who cannot secrete aldosterone? I need to write a report.

· The main substitute for aldosterone is fludrocortisone.

· Hormone replacement for kidney function usually involves several hormones.

· Addison’s disease is where the adrenal cortex produces insufficient hormones.

· Hormone replacement therapy can enable patients to manage symptoms (such as fluid retention and high blood pressure).

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it casues the kidney to conserve water by concentrating the urine and reducing urine volume. it has nine amino acidspepitide which is secreted by the pituitary gland and released when body is low of water
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What are three differences and two similarities between active and passive transport?

Similarities:

Both involve ion movement. Both use ion channels to move ions across the cell membrane, in or out of the cell.

Differences:

Passive Transport (or Diffusion) moves ions from high concentration to low, using no metabolic energy. Active Transport moves ions from low concentration to high, using metabolic energy in the form of ATP. Active Transport uses an ion pump (or Sodium/Potassium pump) to move 3 sodium ions out of the cell and 2 potassium ions in to the cell through the energy of 1 ATP molecule.

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Differences

Passive transport doesn't require energy (ATP), active transport does require energy.

Passive transport moves molecules WITH the concentration gradient (high to low), while active transport moves molecules AGAINST the concentration gradient (Low to High).

Similarities

They both allow the cell to maintain homeostasis by maintaining an equilibrium of subtances in and out of the cell.

They both involve moving material across or through the plasma membrane.

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How do these organelles assist each other by working together:

Nucleolus and Ribosomes

Endoplasmic reticulum (ER) and Ribosomes

 

 

 

The nucleolus is located within the nucleus and it makes ribosmes. Ribosomes are the sites where the cells assemble proteins according to instructions directions of DNA. The ribosomes move out of the nucleus into the cytoplasm in order to make proteins. These ribosomes attach to the endoplasmic reticulum, called the rough endoplasmic reticulum where they carry out protein synthesis
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The volume of water in a cell governed mainly by the amount of ____ in the cytoplasm. is it protein, NA+, or K+ ?

Potassium (K+) and sodium (Na+), both ions of positive charge, or cations, both regulate the amount of water moving in and out of cells. Water moves across the cell membrane in either direction, entering or leaving the cell; which direction it goes is contingent upon the relative concentrations of these two ions. Sodium is an extracellular (outside the cell) cation, whereas potassium is an intracellular (inside the cell) cation
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What are mesosomes and how do they work?

Mesosomes are part of the structure of the plasma membrane. You'll find them lining the cell wall. They are clumped and folded together, to maximize their surface area. This is important because it is needed for cell respiration, which is a function of the mesosomes. These folds can become distinct vesicles, which can then be used to contain material, keeping it distinct from the remainder of the cell.

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Mesosomes are areas in the cell membrane of prokaryotic (bacterial) cells that fold inward. They play a role in cellular respiration, the process that breaks down food to release energy.

In Eukaryotes, the majority of this process occurs in mitochondria. The third, and final, step of cellular respiration (electron transport chain) occurs in the space between the two membranes of the mitochondria. This step is critical to the cell as most of the energy from food is released during this stage. Since Prokaryotes do not contain membrane bound organelles, they need a different approach. Instead, they use the mesosomes as a site for the electron transport chain.

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Mesomes are the principal sites of respiratory enzymes, can easily be demonstrated in gram positive bacteria, are essential in bringing about cell division, are convoluted invaginations of the plasma membrane and are also called as chondroid
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What are bacterial cells and how are they arranged?

THE COCCUS:

arrangements based on their planes of division. a. Division in one plane produces either a diplococcus or streptococcus arrangement. b. Division in two planes produces a tetrad arrangement. A tetrad: cocci arranged in squares of 4

d. Division in random planes produces a staphylococcus arrangement. 2. The rod or bacillusTHE BACILLUS:

arrangement.a. bacillus: single bacilli

3. The spiralSpirals come in one of three forms, a vibrio, a spirillum, or a spirochete. a. vibrio: a curved or comma-shaped rod

Trichome-forming, sheathed, stalked, filamentous, square, star-shaped, spindle-shaped, lobed, and pleomorphic.

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All cells can be placed into one of two groups: Prokaryotic or Eukaryotic. Prokaryotes tend to be smaller and simpler in structure while Eukaryotes tend to be larger and more complex since they contain membrane-bound organelles (structures that perform specialized jobs within the cell), like the nucleus. Prokaryotes, on the other hand do not contain a nucleus or any other organelles.

Bacterial cells consist of a circular chromosome (genetic information) which is found in the nucleoid region. The cell is filled with cytoplasm (jelly like goo that fills all cells). There are also ribosomes floating around in the cytoplasm (their job is to make protein using the instructions from the DNA). A cell membrane wraps around the cell to control what gets in and out of the cell. A rigid cell wall can be found outside of the membrane to offer support and protection to the cell. Usually there is also some sort of appendage to assist in the movement of the cell. It can be a long, whiplike tail (like on a sperm) called a flagellum, or many small hairlike growths that the cell uses like little oars called cilia.

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The layers that surround the prokaryotic cell are referred to collectively as cell envelope. The structure and organization of the cell envelope differs in gram­-positive and gram-negative bacteria. The cell envelope of gram-positive cells is relatively simple consisting of 2-3 layers: the cytoplasmic membrane, a thick peptido­glycan layer and some bacteria have an outer layer, either a capsule or an S-layer (slime layer). The cell envelope in gram-negative bacteria is highly complex multilayered structure
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What is the advantage to the cell of having different organelles that carry out specialized functions?

The advantage to the cell is that it is more efficient to have membrane-bound organelles specializing in certain functions, than in spreading the cell's necessary functions randomly throughout the cell. The organelles can also be in logical proximity to others that have related functions. For example, organelles producing proteins within the cell can be near other organelles involved in transporting the proteins out of the cell
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How are electric potential and the corresponding signal produced in the heart?

The heart has several sets of pacemaker cells, which are capable of producing an electrical impulse through chemical changes.

The resting potential of the pacemaker cell results from a slow leak of positively charged potassium ions through the cell's membrane.

Pacemaker cells are able to depolarize (called the "upstroke") and make themselves more positively charged by slowing the outflow of potassium ions and at the same time allowing sodium and calcium to come in.

Once it has reached the threshold potential, these flows reverse. Sodium and calcium are blocked from entering and the potassium ions are allowed back out.

This shift from negative to positive to negative again causes the action potential or electrical impulse.