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FOOD AND NUTRITION DURING PREGNANCY



It is important for a pregnant woman to eat a healthy diet. She has to eat a variety of foods, including dairy products and several fruits and vegetables which contribute to a healthy pregnancy. Some specific nutritional needs for pregnancy include:

Folic acid (also called folate or Vitamin B9) is strongly needed at the start of pregnancy. Folic acid is needed for the closing of fetus neural tube. It thus helps prevent spina bifida, a very serious birth defect. Folates (from folia, leaf) are abundant in spinach (fresh, frozen or canned), and are also found in green vegetables, salads, melon, and eggs. In the United States and Canada, most wheat products (flour, noodles) are supplemented with folic acid.

Calcium and iron are particularly needed by the rapidly growing fetus. Pregnant women should eat enough dairy products (for calcium) and red meat (for iron) if they are not lactose intolerant. Women who do not eat dairy or meat can obtain calcium and iron from soy milk and juice, soybeans, and certain leafy greens. Care providers may prescribe iron pills if pregnant women develop iron deficiency anemia. Calcium is effective only if women also obtain enough vitamin D. The best way to get vitamin D is to sunbathe each day for 10-15 minutes. Salmon and fatty fishes are also good sources of vitamin D.

Fluoride helps to build strong teeth by changing the nature of calcium crystals: if water or salt does not contain fluoride, it is wise to take fluoride mini-pills at the end of pregnancy and during breast-feeding (but high doses are toxic). Some pregnant women suffer edema, and are told not to eat (too much) salt.

Fat (from salmon, trout, tuna, herring,sardine, mackerel, and some chicken eggs) is needed to build neuron membranes. Thus fatty fish intake during pregnancy may provide nutrition for proper brain and retina development of the fetus. However, large fish such as tuna and swordfish may contain too much toxic mercury. Fish two or three times a week seems to bring enough good fat, but not too much mercury.

 

Ex. 22. Pronounce and memorize the words to the theme studied:

Derive походити; proceed продовжувати; evagination евагінація, випинання; eventually зрештою; foregut передня кишка; elongate пролонгувати, подовжувати; conjunction з’єднання, об'єднання.

 

Ex. 23. Read the following text and put 10-11 questions on it. Get ready to inform your fellow-students what text deals with.

DEVELOPMENT OF THE ORGAN SYSTEMS

The major organ systems appear and begin to develop during the embryonic period.

Skin

The epidermis of the skin is derived from ectoderm, and the dermis is derived from the mesoderm. Nails, hair, and glands develop from the epidermis.

Skeletal system

The skeleton develops by intramembranous bone formation or endochondrial bone formation.

Muscular system

Myoblasts are multinucleated cells that produce skeletal muscle fibers. The growth of the muscle occurs by an increase in the number of muscle fibers. The total number of muscle fibers is established before birth. Muscle enlargement after birth is due to an increase in the size of individual fibers.

Nervous system

The nervous system is derived from the neural tube and neural crest cells. Closure of the neural tube begins in the upper-cervical region and proceeds into the head and down the spinal cord. The central cavity of the neural tube becomes the ventricles of the brain and the central canal of the spinal cord. The nerve cells that form the peripheral nervous system are located either within the neural tube or are derived from neural crest cells.

Endocrine system

The thyroid gland originates as an evagination from the floor of the pharynx in the region of the developing tongue and moves into the lower neck, eventually losing its connection with the pharynx. The parathyroid glands migrate inferiorly and become associated with the thyroid gland. The pancreas originates as two evaginations from the duodenum, which come together to form a single gland. The adrenal medulla arises from neural crest cells, and the adrenal cortex is derived from mesoderm.

Cardiovascular system

The heart develops from two endothelial tubes, which fuse into a single heart tube. Blood vessels form from small masses of mesoderm that become blood vessels on the outside and blood cells on the inside. These masses fuse to form the cardiovascular system.

Respiratory system

The lungs begin to develop as a single evagination from the foregut in the region of the future esophagus. This evagination branches to form two lung buds. The lung buds elongate and branch, first forming the bronchi that project to the lobes of the lungs and then the bronchi that project to the lobules of the lungs. This branching continues until approximately 17 generations of branching have occurred.

Urinary system

The kidneys develop from mesoderm located between the somites and the lateral portion of the embryo. The urinary system develops in three stages from the head to the tail of the embryo. The ducts join the digestive tract.

Reproductive system

Reproductive system develops in conjunction with the urinary system. Hormones are very important to sexual development of the human.





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