Bio Question!? Help please

Question

1) the first organ transplant ever done were kidney transplants. A kidney of a healthy person was removes and denoted to an identical twin whose 2 kidneys were failing. Why would a transplant between identical twins not result in rejection?

2) Describe inhalation, gas exchange, and exhalation in a human. List all the structures of the respiratory system and their functions, in order, for each process.

3) A person has just begun a meal of foods containing starches, fats, and proteins. Describe the state of that food, physically and chemically, by the time it (a) leaves the mouth (b) leaves the stomach (c) has been digested in the interior of the small intestine; and (d) has moved through the colon

Thanks in advance everyone!

Answer 1

Long answer, here goes!

1) the first organ transplant ever done were kidney transplants. A kidney of a healthy person was removes and denoted to an identical twin whose 2 kidneys were failing. Why would a transplant between identical twins not result in rejection?

IANSWER  Identical twins have the same surface antigens on their cells so it would not be recognised as 'foreign' by the recipients immune system and they would not produce antibodies to reject the tissue.

2) Describe inhalation, gas exchange, and exhalation in a human. List all the structures of the respiratory system and their functions, in order, for each process.

ANSWER Inhalahtion through the nose and mouth>trachea.>bronchi>lungs (bronchioles)> air sacs/alveoli>diffusion of oxygen into red blood cellsand CO2 in the opposite direction. Exhalation from air sacs/alveoli > bronchioles> bronchi> trachea>out through nose and mouth.

Additional information:

Breathing movements via two sets of muscles, the intercostal muscles between the ribs and the diaphragm at the bottom of the thorax.

During inhalation The diaphragm and intercostals contract,  The diaphragm moves down and the ribcage moves up and out, decreasing preesure in the lungs and air is drawn in.

During exhalation The diaphragm and intercostals relax , the diaphragm moves up and the ribcage is moved down and in forcing air out of the lungs.

The respiratory passages have rings of cartilage to keep the breathing passages open.

The respiratory passages are lined with tiny hairs called cilia which work along with mucus to trap pathogens and dirt and sweep them upwards to keep the respiratory passages clean.

3) A person has just begun a meal of foods containing starches, fats, and proteins. Describe the state of that food, physically and chemically, by the time it (a) leaves the mouth (b) leaves the stomach (c) has been digested in the interior of the small intestine; and (d) has moved through the colon

ANSWER

(a) Chewing mixes the food with saliva containing salivary amylase which digests starch to maltose. Chewing also breaks food down physically so that it can be swallowed. Swalled food is referred to as a bolus and passes down the oesophagus by peristalsis to the stomach.

(b) In the stomach the food is further broken down by physical churning of the food by rhythmical contraction of the stomach wall muscles. The food is mixed with gastric juice produced by the cells in the stomach lining. Gastric juice contains the enzyme pepsin and hydrochloric acid to produce the optimum pH for the enzyme to work. pepsin breaks down protein to smaller fractions called peptides. The semi liquid food is called chyme.

(c) Enzymes produced by the pancreas complete the chemical breakdown of food in the small intestines:

Maltose  > Glucose

Peptides > amino acids

Lipids > fatty acids and glycerol

Glucose and amino acid are absorbed directly into the blood stream via capillaries in the villi of the intestine.

Glycerol and fatty acids are absorbed into tiny lymphatic vessels in the villi..

At the end of the small intestine all that remains is undigested food (which we do not have the enzymes to futher digest) and water.

(d)  In the large intestine (colon) useful water is reabsorbed into the bloodsteam and the undigested food is compacted into faeces and stored in the r****m before elimination at the a**s.

Hope this helps!

Answer 2

I think you should do your homework...as in, read the book.