Biochemistry

Question 1

Describe homeostasis.

Answer 1

Homeostasis is that property of a system, which regulates its internal
environment so as to maintain a stable, constant condition.

Question 2

Which are the major elements of the human body?

Answer 2

OCH N:
Oxygen - 65%
Carbon - 18%
Hydrogen - 10%
Nitrogen - 3%

Question 3

Which are the lesser elements of the human body?

Answer 3

Ca, P, K, S, Na, Cl, Fe, Mg

Question 4

Name some trace elements of the human body.

Answer 4

Aluminium, Boron, Chromium, Cobalt, Zinc, Copper, Flourine, Tin, Vanadium, Iodine, Manganese, Molybdenum & Selenium.

Question 5

What are the inorganic compounds of the body?

Answer 5

Water, acids, bases and salts.

Question 6

Name some properties of the most abundand inorganic compound water.

Answer 6

High heat capacity
High heat of vaporization
Polar solvent properties
Reactivity
Transport medium
Lubricates
Cushioning

Question 7

What differs an acid from a base and from a salt?

Answer 7

An acid drops a hydrogen ion, a base drop a hydroxide ion and a salt doesn’t drop any of these when solved in water.

Question 8

Describe iodine deficiency.

Answer 8

Thyroid hormones need iodine.
Can cause metabolic problems and retardation.
Prevent with iodized salt.

Question 9

What are the the main organic compounds in the body?

Answer 9

Carbohydrates, fats and proteins.

Question 10

Which are the subgroups of carbohydrates?

Answer 10

Monosaccharides, disaccharides and polysaccharides.

Question 11

Name five monosaccharides.

Answer 11

Glucose (druvsocker)
Fructose (fruktsocker)
Galactose
Ribose (RNA)
Deoxyribose (DNA)

Question 12

Name three disaccharides.

Answer 12

Sucrose (glucose and fructose)
Maltose (glucose)
Lactose (glucose and galactose)

Question 13

Describe lactose intolerance.

Answer 13

Hypolactasia. Lack of enzyme lactase which breakes lactose into its building blocks glucose and galactose.

Question 14

Name three polysaccharides.

Answer 14

Glycogen
Starches
Cellulose
(They are all made out of glucose)

Question 15

Name three lipids.

Answer 15

Fatty acids
Triglycerides
Phospholipids

Question 16

What are the functions and the properties of fatty acids?

Answer 16

They are single lipids
Building block for triglycerides and phospholipids
Contain energy
They can be saturated with no double bonds of the carbon or unsaturated with these double bonds and a crooked shape.

Question 17

What are the functions and the properties of triglycerides?

Answer 17

They contain a lot of energy and has an unlimited storage capacity.
Made out of three fatty acids and one glycerol molecule.
Recognized as our fats and oils, which can be either solid or liquid in room temp.

Question 18

What are the functions and the properties of phospholipids?

Answer 18

Made out of two fatty acids, one glycerol molecule and one phosphate group.
Polar (hydrophilic) head and nonpolar (hydrophobic) tails.
Make up our cell membranes with bilayer sheets.
A ball of phospholipids is called a micelle and a double membrane layer sphere is called a liposome. The latter are used in endo- and exocytosis.

Question 19

Which are the four nitrogenous bases?

Answer 19

Adenine and Thymine (Uranine in RNA)

Cytosine and Guanine

Question 20

What is the nucleotide composed of?

Answer 20

Nitrogenous base, deoxyribose and a phosphate group.

A gene consists of about 3000 nucleotides.

Question 21

What are the properties and functions of DNA?

Answer 21

Double stranded
Located in nucleus and contain genetic info (basic instructions for building proteins)
Replicates before cell division

Question 22

What are the properties and functions of RNA?

Answer 22

Single stranded
Is found outside the nucleus
mRNA - Messenger
tRNA - Transporter
rRNA - Ribosome

Question 23

What is the structure of amino acids?

Answer 23

Amino group (H-H-N) - Side chain of carbon and hydrogen - Carboxyl group (C=O-OH)

Question 24

What are the abbreviations EAA and BCAA short for?

Answer 24

Essential Amino Acids (important for life) and Branched Chain Amino Acids (good before work out).

Question 25

How do the amino acids bond to form proteins?

Answer 25

Using peptide bonds and therefore creating water as biproduct. This is called Dehydration synthesis, and its reversal is called Hydrolysis. The carboxyl group of one acid binds to the amino group of the other acid.

Question 26

What are the four different levels of structure of a protein?

Answer 26

Ordinary structure - Combinations of nucleotides, e.g. the amino acid sequence.
Secondary structure - Alpha helix and Beta pleated sheet.
Tertiary structure - 3D shape of polypeptide chain.
Quaternary structure - Arrengement of multiple polypeptide chains together.

Question 27

Name some functions of proteins.

Answer 27

Creation of enzymes and antibodies.
Cell adhesion.
Movement.
Storage.
Messenger.
Transporter.
Receptor.
Structure.

Question 28

Describe the condition sickle cell anemia.

Answer 28

Erythrocyte (RBC) disorder when there are not enough healthy erythrocytes to carry oxygen. Caused by a damage in the protein hemoglobin due to wrongly translated RNA.

Question 29

What is ATP short for, what is its chemical structure, and how is it made?

Answer 29

Adenosine triphosphate.
Nitrogenous base adenine, which together with the monosaccharide ribose create adenosine. Adenosine bonds in its own turn to three phosphate groups.
Either by cellular respiration in the mitochondria, anaerobic glycolysis, or by creatine phosphate.

Question 30

What are the three main types of transport methods across the plasma membrane?

Answer 30

Passive, which can be divided into diffusion and osmosis. Diffusion can be divided into simple and facilitated.
Active, which can be divided into primary and secondary.
Vesicle, which really should be categorized under active since it needs ATP

Question 31

What is diffusion?

Answer 31

The passive movement of molecules along their concentration gradient. Could depend on distance, concentration, size, temp, weight, surface area.

Facilitated diffusion is when a membrane protein is assisting a specific substance across. Ex glucose, fructose, urea and vitamins.

Question 32

What is osmosis?

What is an isotonic, a hypotonic, and a hypertonic solution?

Answer 32

The spontaneous net movement of solvent across a selectively permeable membrane in the direction that tend to equalize the solute concentration.

Isotonic means that two solutions has the same osmolarity. Hypotonic solution means that water diffuses into the cell, and in hypertonic the water diffuses out of it.

Question 33

What is there to know about active transport?

Answer 33

Requires energy (about 40% of the cells energy need)
Can be either primary or secondary (this is the indirect use of energy e.g. hitchhiking of ions when another ions is pump through the membrane)
Ex the 3Na+/2K+ pump is primary active transport for Na and secondary for K
Important for osmotic balance and electric signals

Question 34

What is there to know about vesicular transport?

Answer 34

Uses ATP so technically an active transport
Bud off a membrane
Endocytosis is when it is transported into the cell, can be either phagocytosis of big particles or bulk-phase of small.
Exocytosis is transport out of the cell like waste or various important products (secreting cells).
Transcytosis is the transportation i vesicles right across and through the cell.