Chapter 4 Flashcards
What types of tissue are normally found in skin?
All 4 types of tissue:
Why would burn damage to the skin represent such a serious challenge to a person’s health?
Skin burns affect homeostasis of fluid levels and pH levels in the body
Why would it be more difficult to produce new dermis in the laboratory than new epidermis?
The dermis contains blood vessels, nerves, and glands, whereas the epidermis does not.
What is tissue?
Tissue is composed of specialized cells of the same type that perform a common function in the body. There are 4 types of tissue in the body.
What are the 4 types of tissue?
- Connective tissue
- Muscular tissue
- Nervous tissue
- Epithelial tissue
Connective tissue
Type of tissue that binds structures together, provides support and protection, fills spaces, stores fat, and forms blood cells; adipose tissue, cartilage, bone, and blood are types of connective tissue.
Muscular tissue
Moves the body and its parts
Nervous tissue
Receives stimuli and conducts nerve impulses
Epithelial tissue
Covers body surfaces and lines body cavities
How are cancers classified?
According to the type of tissue from which they arise.
How does cell division affect the chances of developing cancer?
The rate of cell division affects the chances of developing cancer. The higher the rate of cell division, the greater the chances. Because epithelial and blood cells reproduce at a high rate, carcinomas and leukemias are common.
What three components do connective tissues have in common?
- Specialized cells
- Ground substance
- Protein fibers
Ground Substance
A noncellular material that separates the cells. It varies in consistency from solid (bone) to semifluid (cartilage) to fluid (blood)
What are the three possible typed of fibers?
- Collagen fibers
- Reticular fibers
- Elastic fibers
Collagen fiber
A white fiber in the matrix of connective tissue; gives flexibility and strength
Reticular fibers
Very thin collagen fibers in the matrix of connective tissue, highly branched and forming delicate supporting networks
Elastic Fibers
Yellow fiber in the matrix of connective tissue, providing flexibility
In which two forms do fibrous tissues exist?
- Loose fibrous tissue
- Dense fibrous tissue
What is a fibroblast?
A cell in connective tissue that produces fibers and other substances
What is a Matrix?
Unstructured semifluid substance that fills the space between cells in connective tissues or inside organelles
Loose fibrous connective tissue
Areolar tissue; Tissue composed mainly of fibroblasts widely separated by a matrix containing collagen and elastic fibers
Adipose tissue
Connective tissue in which fat is stored
Adipocytes
The cells of Adipose tissue. Adipocytes are crowded and are filled with liquid fat.
Dense fibrous connective tissue
Type of connective tissue containing many collagen fibers packed together; found in tendons and ligaments
Tendon
A strap of fibrous connective tissue that connects skeletal muscle to the bone.
Ligament
A tough cord or band of dense fibrous connective tissue that joins bone to bone at a joint
What are the two main supportive connective tissues?
- Cartilage
- Bone
Cartilage
Connective tissue in which the cells lie within lacunae separated by a flexible proteinaceous matrix
What purpose to cartilage and bone serve to the body?
They provide structure, shape, protection, and leverage for movement. Cartilage is more flexible than bone because it lacks mineralization of the matrix.
Lacunae
(sing., lacuna); A small pit or hollow cavity, as in bone or cartilage, where a cell or cells are located.
Of what is the matrix of cartilage formed?
Cells called chondroblasts and chondrocytes
How are the three types of cartilages distinguished form one another?
By the type of fiber found in the matrix
Hyaline cartilage
Cartilage whose cells lie in lacunae separated by a white, translucent matrix containing very fine collagen fibers. It is found in the nose, the ends of long bones, and the ribs, and forms rings in the walls of respiratory passages.
Elastic Cartilage
A type of cartilage composed of elastic fibers, allowing greater flexibility. It is found in the framework of the outer ear.
Fibrocartilage
Cartilage with a matrix of strong collagenous fibers. It is found in structures that withstand tension and pressure, such as the disks between the vertebrae in the backbone and the cushions in the knee joint.
Bone
Bone consists of an extremely hard matrix of inorganic salts, notably calcium salts. These salts are deposited around protein fibers, especially collagen fibers. The inorganic salts give bone rigidity. The protein fibers provide elasticity and strength.
What is responsible for the formation of matrix in bone tissue?
Cells called osteoblasts and osteoclasts
Compact bone
A type of bone that contains osteons consisting of concentric layers of matrix and osteocytes in lacunae
Spongy bone
Porous bone found at the ends of long bones where red bone marrow is sometimes located. It also surrounds the bone marrow cavity.
Blood
A fluid connective tissue consisting of formed elements and plasma and is located in blood vessels. Blood transports nutrients and oxygen to tissue fluid.
Tissue fluid
A fluid that surrounds the body’s cells; consists of dissolved substances that leave the blood capillaries by filtration and diffusion. It removes carbon dioxide and other wastes from cells, distributes heat, and plays a role in fluid, ion, and pH balance.
Red blood cells
Small, biconcave, disk-shaped cells without nuclei. Formed element that contains hemoglobin (responsible for their red color) and carries oxygen from the lungs to the tissues; also called erythrocyte
White blood cells
A type of blood cell that is transparent without staining and protects the body from invasion by foreign substances and organisms; also called leukocyte.
Platelets
Fragments of giant cells present only in bone marrow. When a blood vessel is damaged, platelets form a plug that seals the vessel and injured tissues release molecules that help with the clotting process.
Lymph
A clear (sometimes yellowish) fluid derived from the fluids surrounding the tissues. It contains white blood cells.
What purpose does a Lymphatic vessel serve?
They absorb excess tissue fluid and various dissolved solutes in the tissues. They transport lymph to particular vessels of the cardiovascular system. They absorb fat molecules from the small intestine.
Describe the three general categories of connective tissue, and provide some examples of each type.
■ Fibrous connective tissue (adipose tissue and dense fibrous connective tissue)
■ supportive connective tissue (cartilage and bone)
■ Fluid connective tissue (blood and lymph)
Three types of vertebrate muscular tissue
■ Skeletal muscle
■ Smooth muscle
■ Cardiac muscle
Muscular tissue
Tissue that is specialized to contract. It is composed of cells called muscle fibers, which contain actin and myosin filaments. The interaction of these filaments accounts for movement.
Skeletal muscle
also called voluntary muscle; attached by tendons to the bones of the skeleton. When it contracts, body parts move.
Striated
Having bands; in cardiac and skeletal muscle, alternating light and dark crossbands produced by the distribution of contractile proteins.
Smooth muscle
Nonstriated, involuntary muscle tissue found in the walls of internal organs; also called visceral muscle
Cardiac muscle
Striated, involuntary muscle found only in the heart. Its contraction pumps blood and accounts for the heartbeat
Nerve Tissue
Tissue that contains nerve cells (neurons), which conduct impulses, and neuroglia, which support, protect, and provide nutrients to neuron.
What three primary functions does nerve tissue serve?
■ Sensory input
■ Integration of data
■ Motor output
Neuron
A nerve call that has three parts:
■ Dentrites
■ a cell body
■ an Axon
Dentrites
An extension that receives signals from sensory receptors or other neurons
Cell Body
Contains most of the cell’s cytoplasm and the nucleus
Axon
An extension that conducts nerve impulses.
Neuroglia
Nonconducting nerve cells that are intimately associated with neurons and function in a supportive capacity.
Microglia
In addition to supporting neurons, they engulf bacterial and cellular debris
Astrocytes
Provide nutrients to neurons and produce a hormone known as glial-derived neurotrophic factor (GDNF)
Oligodendrocytes
Form the myelin sheaths around fibers in the brain and spinal cord.
Epithelial Tissue
Also called epithelium; Consists of tightly packed cells that form a continuous layer. Epithelial tissue covers surfaces and lines body cavities. It has a protective function but can also be modified to carry out secretion, absorption, excretion, and filtration.
Basement Membrane
A thin layer of various types of carbohydrates and proteins that anchors the epithelium to underlying connective tissue.
Transitional Epithelium
Tissue that changes in response to stress. It forms the lining of the urinary bladder, the ureters, and part of the urethra as all are organs that may need to stretch.
Integumentary System
An organ system consisting of skin and various other organs, such as hair, nails, sweat glands, and sebaceous glands.
What functions does the skin serve?
It protects underlying tissues from physical trauma, pathogen invasion, and water loss. It helps regulate body temperature. It synthesizes certain chemicals that affect the rest of the body. It also contains sensory receptors such as touch and temperature receptors.
What is the epidermis made up of?
Stratified squamous epithelium
How does damaged skin repair itself?
The renewal of skin is derived from stem cells.
Autografting
The process of taking skin from another part of the patient’s body for grafting
Allografting
The process of taking skin from another person’s body or that of a cadaver for grafting onto a patient.
