Biomedical Engineering Reference
In-Depth Information
HAIR SHAFT
EPIDERMIS
WHITE
BLOOD
CELLS
DERMIS
RED
BLOOD
CELLS
HAIR
FOLLICLE
SEBACEOUS
GLAND
ARRECTOR
PILI MUSCLE
FAT
SWEAT
GLAND
(b)
(a)
DENDRITES
CARDIAC
AXON
SKELETAL
CELL BODY
NODE OF
RANVIER
NUCLEUS
SMOOTH
PRESYNAPTIC
TERMINALS
(c)
(d)
FIGURE 3.16
Four tissue types. Skin (a) is a type of epithelial tissue that helps protect the body. Blood (b) is a
specialized connective tissue. The three types of muscle tissue (c) are cardiac, skeletal, and smooth. Motor neurons
(d) are a type of nervous tissue that conducts electrical impulses from the central nervous system to effector organs
such as muscles.
(Figure 3.16b), bone, cartilage, and adipose tissue. Muscle tissue provides movement for the
body through its specialized cells that can shorten in response to stimulation and then return
to their uncontracted state. Figure 3.16c shows the three types of muscle tissue: skeletal
(attached to bones), smooth (found in the walls of blood vessels), and cardiac (found only
in the heart). Nervous tissue consists of neurons (Figure 3.16d) that conduct electrical
impulses and glial cells that protect, support, and nourish neurons.
3.4 MAJOR ORGAN SYSTEMS
Combinations of tissues that perform complex tasks are called organs, and organs that
function together form organ systems. The human body has 11 major organ systems: integ-
umentary, endocrine, lymphatic, digestive, urinary, reproductive, circulatory, respiratory,
nervous, skeletal, and muscular. The integumentary system (skin, hair, nails, and various
