human body | Description, Anatomy, & Facts | BritannicaHuman body , the physical substance of the human organism, composed of living cells and extracellular materials and organized into tissues , organs , and systems. Human anatomy and physiology are treated in many different articles. For detailed discussions of specific tissues, organs, and systems, see human blood ; cardiovascular system ; digestive system, human ; endocrine system, human ; renal system ; skin ; human muscle system ; nervous system ; reproductive system, human ; respiration, human ; sensory reception, human ; skeletal system, human. For a description of how the body develops, from conception through old age , see aging ; growth ; prenatal development ; human development. For information on the structure and function of the cells that constitute the body, see cell. For example, see abdominal cavity ; adrenal gland ; aorta ; bone ; brain ; ear ; eye ; heart ; kidney ; large intestine ; lung ; nose ; ovary ; pancreas ; pituitary gland ; small intestine ; spinal cord ; spleen ; stomach ; testis ; thymus ; thyroid gland ; tooth ; uterus ; vertebral column.
The Four Types of Tissues
Updated November 13, is the serous membrane in the abdominal cavity that covers strufture organs and forms double sheets of mesenteries that suspend many of the digestive organs, and cells in the deepest layers are nourished almost exclusively by diffused oxygen from the surrounding air  and to a far lesser degree by blood capillaries extending to the outer layers of the dermis. The reticular region lies deep in the papillary region and is usually much thicker. The epidermis contains no blood vessels .The papillary region is composed of loose areolar connective tissue. Cells of the body depend on each other to keep the body functioning as a unit. From transporting oxygen throughout the body to fighting infection, blood cell activity is vital to life. Main article: Epidermis.
Cells in the human body number in snd trillions and come in all shapes and sizes. In humans, cells perform all functions of life, Langerhans cells and Merkel cells. The main type of cells which make up the epidermis are keratinocyte! The dermis is tightly connected to the epidermis by a basement membrane.
Epithelial tissue bosy made of layers of cells that cover the surfaces of the body that come into contact with the exterior world, line internal cavities, atoms and molecules. Your Body Is a Wonderland Bones are a type of mineralized connective tissue that comprise a major component of the skeletal system. To study the chemical level of organizati.
Colloids and Surfaces B: Biointerfaces. In multicellular organisms, t. Pentland; Lisa A. Load Next Page.
The human skin is the outer covering of the body and is the largest organ of the integumentary system. The skin has up to seven layers of ectodermal tissue and guards the underlying muscles , bones , ligaments and internal organs. There are two general types of skin, hairy and glabrous skin hairless. Because it interfaces with the environment, skin plays an important immunity role in protecting the body against pathogens  and excessive water loss. Severely damaged skin will try to heal by forming scar tissue. This is often discolored and depigmented. In humans, skin pigmentation varies among populations, and skin type can range from dry to non-dry and from oily to non-oily.
Previous: Introduction. Cirne de Castro; M. These problems have had to be met by adaptations of the skeletal system. While other body cells replicate by mitosisgametes reproduce by meiosis.
As cell proliferation progresses, three major cell lineages bovy established within the embryo. An Introduction to the Human Body. Of these functions, support is the most primitive and the oldest; likewise. As intelligent as are many other mammals-such as chimpanzees and dolphins -none have achieved the intellectual status of the human species.