BLOG FOR NGCS STUDENTS 2009-2010

IN THE FOLLOWING DAYS I WILL BE PREPARING YOUR NEW CHEMISTRY, PHYSICS AND BIOLOGY SITE FOR 2009-2010 YEAR SCHOOL.

HERE YOU WILL RECEIVE ALL INFORMATION RELATED TO YOUR CLASSES AND SOME OF YOUR WORK AND VIDEOS FROM THE CLASS WILL ALSO BE UPLOADED. IN THE MEANTIME... KEEP ENJOYING YOUR VACATIONS AND PLEASE VISIT THE PAGE FOR FURTHER INFORMATION.

GOD BLESS YOU ALL!!!

CHAPTER 3 (some answers)

5.a ---- 1.36 EXP 23 atoms of CH4, 2.72 EXP 22 molecules of CH4


5.c ---- 3.011 EXP 20 atoms


6.a ---- 2.658 mol Na


6.d ---- 1.99 EXP -4 mol CO2


6.e ---- 0.09997 ml Zn


7.a ---- 69 g NH4Cl


7.c ---- 0.271 g NO2


7.f ---- 2.001 g C2H5OH


8.a ---- 3.02 EXP 22 molecules of MgCl2, 9.07 EXP 22 atoms of MgCl2


9.b ---- 0.314 mol NH4Cl


9.d ---- 2.71 EXP 23 molecules CO


9.f ---- 1.08 EXP -13 mol H2O


9.h ---- 5.56 EXP 3 mol glucose


ALSO TRY TO FIND:
a) # of grams in 100 mol H --- 100g
b) # of atoms in 5g O --- 1.88 EXP 23 atoms
c) The mass of 6.022 EXP 23 atoms O --- 16g

VITAMINS OF THE HUMAN BODY

Vitamins are complex organic molecules. Their existence in the human body is necessary (small amounts). Many vitamins are coenzymes and play an important role in cell reactions. The human organism is able to produce only one vitamin (D), the intake of all the others must be part of our diet.

I will describe some of the liposoluble and hydrosoluble vitamins that are important to humans. Each vitamin has a specific function, but in general terms their function is to control and regulate biochemical reactions.

Vitamins are found in different kinds of food, especially in fresh fruits and vegetables. Although they are required in small quantities, lack of vitamins in daily diet can cause serious physiological disorders. In Honduras, the most common disorders due to vitamins deficiency are: rickets, dermatitis, anemia and in some cases even fatigue, depression and muscle aches. A high percentage of children live under these conditions because of an incomplete diet.

IMPORTANT VITAMINS FOR HUMANS (RDI= recommended daily intake)

a) Liposolubles: A, D, E K.

Vitamin A:
Function: normal vision, bone development, prevents infections.
Deficiency problems: night blindness.
Main sources: carrots, liver, eggs.

Vitamin D (400 RDI):
Function: Calcium absorption.
Deficiency problems: osteomalacia, rickets.
Sources: sunlight, fish oil.

Vitamin E (30 RDI):
Function: inhibits the oxidation of fatty acids, fertilization.
Deficiency problems: Fragile cell membranes.
Sources: vegetable oils, seeds, grains and eggs.

Vitamin K (RDI: 570-700)
Functions: blood coagulation.
Deficiency problems: hemorrhaging.
Sources: pork liver, vegetables, cabbage, spinach.

HYDROSOLUBE VITAMINS (B1, B2, B6, B12, AND OTHERS)

Vitamin B1 (thiamine):
Functions: Aminoacids and carbohydrates metabolism, it is a coenzyme.
Deficiency problems: beriberi.
Sources: liver, yeast, cereals, meat.

Vitamin B2 (riboflavin):
Functions: coenzymes synthesis.
Deficiency problems: lesions of lips commissures, dermatitis.
Sources: asparagus, bananas, cottage cheese, milk, yogurt, meat, eggs and fish.

Vitamin B6 (pyridoxine):
Functions: coenzymes in the metabolism of aminoacids.
Deficiency problems: dermatitis, digestive system disorders.
Sources: liver, fish, cereals, bread.

Vitamin B12 (cyanocobalamin):
Functions: conezyme in the metabolism of nucleic acids.
Deficiency problems: pernicious anemia.
Sources: liver, chocolate, yolk.

Niacin:
Functions: essecial coenzyme during cell respiration.
Deficiency problems: pellagra (dermatitis and muscle weakness)
Sources: liver, milk, meat and pulses (leguminous crop).

Pantothenic acid:
Functions: component of coenzyme A.
Deficiency problems: there are no deficiencies.
Sources: liver, meat, cereals, pulses.

Folic acid:
Functions: maturation of erythrocytes (red blood cells).
Deficiency problems: Anemia.
Sources: wheat, vegetables, pulses.

Biotin:
Functions: aminoacids’ metabolism, glycogen synthesis.
Deficiency problems: fatige, depression, muscle ache.
Sources: meat, vegetables and pulses.


Vitamin C (ascorbic acid):
Functions: cartilage maintenance, collagen synthesis.
Deficiency problems: scurvy.

Sources: citrus

MAIN ENDOCRINE GLANDS IN HUMANS

Here are some important glands, the hormones they secrete, and some specific functions of such hormones:

1. Hypothalamus (posterior lobe) secretes:

a) Antidiuretic or vasopressin: Promotes the absorption of water by the kidneys.
b) Oxytocin: Stimulates uterus contraction during labor and afterbirth, stimulates nipples for milk production. In men it stimulates ejaculation.

2. Hypothalamus (anterior lobe) secretes:

a) Follicle-stimulating hormone (FSH): In women stimulates the maturation of the follicle. In men stimulates spermatogenesis.
b) a) Luteinizing (LH): Stimulates ovulation and the formation of corpus luteum. In men stimulates the formation of testosterone.
c) Prolactine: Milk production.

3. Thyroid gland secretes:

a) Thyroxin: Stimulates metabolic intensity. It is essential for normal development.

4. Parathyroid secretes:

a) Parathyroid: Activates vitamin D.

5) Pancreas secretes:

a) Insulin: Decreases glucose concentrations in blood.
b) Glucagon: Increases glucose concentrations in blood.

6) Suprarenal medulla secretes:

a) Adrenaline and Noradrenalin: both help in stress control, increase of heart rate, blood pressure and metabolic intensity.

7) Suprarenal cortex secretes:

a) Glucocorticoids and Aldosterone: both increase blood glucose concentration, regulate sugars and lipids metabolism. They are also known for their anti-inflammatory effects.

8) Pineal secretes:

a) Melatonin: Regulates seasonal reproductive cycles. Controls the beginning of puberty in humans.

9) Ovary secretes:

a) Estrogen and Progesterone: both participate in the development and maintenance of female sexual characteristics, and uterine endometrium development.

10) Testes secrete:

a) Testosterone: Development and maintenance of secondary sexual characteristics. Promotes spermatogenesis.