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Academia - Collins Scientific Pocket Dictionaries - Biology
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skeleton
squelette m. ossature f

skeleton) . The animal's rigid frame, which supports and protects the internal organs.
See endoskeleton and exoskeleton.


skin. skin
peau m

leather. A layer of epithelial cells, connective tissue, and accompanying structures covers most parts of the vertebrate body.

A section of mammal skin
Epidermis - dermis
Subcutaneous fat
Touch receiver
The future of pain
Cooler future
Heat receptor
Sweat gland
pressure receptor
vein
Two evils

The skin of mammals consists of two main layers:
(a) Epidermis, which is the outer layer consisting of:

(1) Cornified layer: dead cells that form a tough, protective outer layer.
(2) Granular layer: living cells that eventually form a keratinized layer.
(3) Malpighian layer: cells that actively divide and produce new skin.

(b) Dermis: a thicker layer that contains blood capillaries, hair follicles, sweat glands, and receptor cells sensitive to touch, heat, cold, pain, and pressure.

Under the dermis there is a layer of fat storage cells that also work as a thermal insulator. The functions of mammalian skin are:

(1) Protection from infections and the entry of microorganisms.

(2) Reduce water loss by evaporation.

(3) Acting as a receptor for certain environmental stimuli.

(4) Important in temperature regulation in homoiothermic animals


small intestine
Intestin m grêle

The small intestine. The anterior part of the intestine of a vertebrate animal. In humans, it consists of a duodenum, about thirty centimeters long, and an ileum, about seven meters long. The duodenum receives food from the stomach. See digestion.

smell
odorat m

Smell. The ability of animals to detect odors. The receptor cells for this sense in humans are located in the nasal cavity, and they are sensitive to chemical stimuli. See sensitivity.


smooth muscle
Muscle m lisse

. involuntary muscles smooth muscle. Look


soil. soil
sol m

Soil. The weathered layer of the Earth's crust mixed with living organisms and their decomposition products. The soil components are:

(a) inorganic particles (weathered rocks), (b) water, (c) humus, (d) air, (e) mineral salts, (f) microorganisms, (g) other organics (e.g. earthworms).

The importance of soil is that it:

(a) It constitutes a habitat for a wide diversity of...
Memberships.
(b) Availability of water and mineral salts to plants.
(c) The decomposition of dead organisms in the soil releases minerals that can be used by other living organisms.


soil depletion
Appauvrissement m du sol

Soil impoverishment. Loss of mineral salts from the soil when the crop is harvested. As in the case of soil erosion, this may cause the soil to lose its fertility. Soil impoverishment can be avoided by (a) crop rotation. (b) Adding fertilizers.


soil erosion
Erosion m du Sol

Soil erosion. Loss of mineral salts from the soil as a result of agricultural practices accompanying crop development, such as repeated plowing, deforestation, etc., which makes the mineral-rich upper soil less stable and more vulnerable to the effects of wind and rain. See soil depletion.