Question

Biology/ anatomy of the human body

1. Briefly discuss three structural and two functional characteristics common to the stomach, urinary bladder, and vagina.

2. Why is litmus, which detects changes in pH, an appropriate reagent to use when monitoring the effects of enzymes on lipid digestion?   

3. A drop of Patient X’s blood is mixed separately with Anti-A serum; Anti-B serum; and Anti-Rh serum. No agglutination (clumping) was observed. What is Patient X’s blood type?

4. One ml. of amylase, and one ml. of the starch solution are added to a test tube and incubated in a boiling water bath for five minutes. Five drops of iodine solution are then added to the test tube producing a dark blue / black color. Explain.

Answer 1

A) Stomach

There are four main regions in the stomach: the cardia, fundus, body, and pylorus .

The cardia is the point where the esophagus connects to the stomach and through which food passes into the stomach.

As food reaches the end of the esophagus, it enters the stomach through a muscular valve called the lower esophageal sphincter.

Fuctions: temporary storage for food, which passes from the esophagus to the stomach where it is held for 2 hours or longer.

mixing and breakdown of food by contraction and relaxation of the muscle layers in the stomach. And digestion of food by the help of digestive enzyme present in stomach.

Urinary bladder

the urinary bladder is about the size and shape of a pear.

The urinary bladder is a muscular sac in the pelvis, just above and behind the pubic bone.

When the bladder is empty, the mucosa has numerous folds called rugae. The rugae and transitional epithelium allow the bladder to expand as it fills.

Function: The bladder stores urineurine.

Allowing urination to be infrequent and controlled.

Female reproductive tract

The birth chanel is a fibromuscular tube with anterior and posterior walls – these are normally collapsed and thus in contact with one another.

The shape of the birth chanel is not a round tunnel. In the transverse plane it is more like an “H” lying on the side. At the upper ending, the birth chanel surrounds the cervix, creating two domes : an anterior and a posterior one.

Functions: Sexual intercourse – receives the sperms , assisting in its transport to the uterus.

Childbirth – expands to provide a channel for delivery of a newborn from the uterus.

Menstruation – serves as a canal for menstrual fluid and tissue to leave the body.

B) Litmus cream is made of litmus and a source of fat (usually half and half milk). This litmus cream is mixed with pancreatin and bile so that pancreatin breaks down the fat in the litmus cream. Lipid break down into glycerol and fatty acid. The presence of fatty acids turns the reaction acidic and the color begins to turn pink.

C) the patient blood does not react with anti A, anti B, and anti D. Which indicate the RBC of the patient doesn't contain A or B antigen. And also Rh negative. That is the patient blood group is O negative.

D) during incubation on boiling water bath Amylase enzyme will denatured. The iodine test is used to test for the presence of starch. Amylose in starch is responsible for the formation of a deep blue color in the presence of iodine. The iodine molecule slips inside of the amylose coil. Iodine - KI Reagent: Iodine is not very soluble in water, therefore the iodine reagent is made by dissolving iodine in water in the presence of potassium iodide. This makes a linear triiodide ion complex with is soluble that slips into the coil of the starch causing an intense blue-black color. the iodine in the form of I₃^- ions gets embedded in the helix shape of the amylose and is pushed straight by the starch. A transfer of electrons between the starch and iodine changes the arrangement of electrons and absorbs much of the visible light which gives it its dark blue colour. In the absence of starch the brown color of the aqueous solution remains.