meso-, mes-, mesi-

Organisms inhabiting the seabed in the archibenthal zone, between 200 and 1,000 meters in depth: Mesobenthos include flora and fauna that live at the sea bottom at depths of 100-500 fathoms (180-900 meters).

Soil organisms of intermediate size, from about 40-50 mm in length to a size just visible with the aid of a hand lens (magnifier).

1. The mesoderm, especially in the early states of embryos.
2. The middle of the three cell layers in an embryo, from which connective tissue, muscle, blood, dermis, bone, and other tissues develop.

1. A reference to the middle embryonic germ layer, lying between the ectoderm (outer skin) and the endoderm (inner skin), from which connective tissue, muscle, bone, and the urogenital and circulatory systems develop.
2. Relating to the mesoblast; as, the mesoblastic layer which is the middle germ layer that develops into muscle and bone and cartilage and blood and connective tissue.

The germ layer is a layer of cells produced during the process of gastrulation (series of cellular movements) during the early development of an animal embryo, which is distinct from other such layers of cells, as an early step of cell differentiation (distinguishing one cell from another cell).

The three types of germ layers are the endoderm (innermost layer that develops into the lining of the respiratory and digestive tracts), ectoderm (the outermost of three cell layers of an embryo, from which the epidermis, nervous tissue, and sense organs develop), and mesoderm (the middle of the three cell layers in an embryo, from which connective tissue, muscle, blood, dermis [skin], and bone develop).

The central position of the heart in the chest, as in an embryo.

This position is normal in the fetal (pre-birth) stage, but a malposition (abnormal position) after birth.

1. A double layer of membrane in the developing embryo that attaches the heart to the body wall and the foregut.
2. Epicardium covering the blood vessels which enter and leave the heart.

The dorsal mesocardium connects the heart to the foregut, and the ventral mesocardium connects the heart to the central body wall.

1. The middle layer of the pericarp (part of a fruit that surrounds the seed or seeds, including the skin, flesh, and, in some fruits, the core) of a fruit or ripened ovary; such as, the fleshy part of a peach or plum.
2. The fleshy, middle portion of the wall of a succulent (juicy and pleasant to the taste) fruit between the skin and the stony (seed) layer.

1. A reference to having a head of medium breadth, with a cephalic index between 76 and 80.

The cephalic index is a rating scale which is used to measure the size of the head.

The rating on the cephalic index is obtained by multiplying the maximum width of the head by 100 and dividing that number by the maximum length of the head and the numbers between 75 and 80 are considered normal.

2. Having the cranial cavity of medium capacity which is neither megacephalic (abnormally large head) nor microcephalic (abnormally small head).
3. Etymology: from the Greek word mesos, "middle" + the Greek word kephale, "head" + Greek ikos, "pertaining to". Put the words together and you have "pertaining to (a) medium head."

1. The climate of small areas of the earth's surface which may not be representative of the general climate of the region; such as, a valley, a lake, a plantation, or a city.
2. A climate characterized by moderate temperatures; that is, in the range of 20-30 degrees centigrade.

Also known as mesothermal climate.

The study of mesoclimates or the climates of a natural region of small extent; for example, a valley, a forest, a plantation, and a park.

The climates of small areas of the earth's surface which may differ from the general climate of the district.

To live in conditions in which there is neither an excess nor a deficiency of water.

The peritoneal fold that fixes the colon to the dorsal abdominal wall.

A process from the middle of the coracoid in some animals.

1. A medium-scale enclosed experimental facility, used especially for assessing the impact of pollutants on natural ecosystems.
2. This term refers to a meaning which is between macrocosm (large) and microcosm (very small) ecosystems.

A government by the middle classes: Ruth read that a mesocracy was a kind of ruling system run by the bourgeoise, and excluding both the rich upper class and poor lower class of people.