7. | Match the sentence beginnings with their endings.

1	The bones of the trunk are ...	a
2	The bones of the skull consist
	of...	b
3	The bones of the skeleton	c
	form...	d
4	The large cavity ...	e
5	The breastbone is ...	f
6	Each rib is composed of ...
7	The bones of the skeleton arc	g
	connected together by...
8	The pelvis connects...	h

one large cavity and some smaller cavities.

is called the cranial cavity.

the lower extremities with the trunk.

a head, neck and body.

cranial and facial parts.

a long bone in the middle of the

chest.

the joints or by cartilages and liga­ments.

the spinal column and the chest.

TEXT 2

Cavities, Systems and Organs

Histology is the study of cells and tissues. It deals with the struc­ture and work of the cells, corpuscles and other very small but vitally important structures.

The cell is composed of protoplasm — a jelly-like substance that is neither a solid nor a liquid. It is usually colorless or slightly yellow. It is in the protoplasm that all the functions occur, and for this reason it is called physical basis of life. The protoplasm is made up of two parts: cytoplasm which is surrounded by the cell wall and contains the nucleus. The nucleus usually contains one or more separate bodies called nucleoli.

All the tissues and organs of the body are made up of cells. A tissue is defined as a group of similar cells that do similar work. In the body there are four main types of tissue: 1) epithelium, 2) connective tissue, 3) muscular tissue, 4) nervous tissue.

Cells combine to form tissues, tissues to form organs, organs to form systems and systems to form the complete body. These are the successive steps in the hierarchy of bodily structure and functions.

The organs and structures forming the various systems are found in the cavities of the body. There are three main cavities: the cranial cavity, the thoracic cavity and the abdominopelvic cavity.

The cranial cavity is situated in the head and contains the brain. The thoracic cavity lies in the upper part of the trunk and contains the air passages, the lungs, the heart, and some of the large blood vessels leading to and from it, and the esophagus.

The thorax is separated from the abdomen by a dome-shaped sheet of muscle known as the diaphragm.

The abdominal cavity lies in the lower part of the trunk directly under the diaphragm, which forms its roof. Its walls are made mainly of muscles. The organs found in the abdominal cavity form the ali­mentary or digestive system.

The pelvic cavity is the lowest part of the abdominal cavity. It lies under the abdominal cavity and is continuous with it. The organs con­tained in the pelvis are the bladder, the female reproductive organs and the lower part of the intestine.

Language Development 1 Match the following words with their definitions.

1 tissue	a that of which things are made
2 solid	b waste material
3 urine	c small oval bodies
4 gland	d tissues study
5 sweat	e not hollow
6 substance	f the liquid which comes out of the skin
7 histology	g all the soft inside parts of the body