Quiz 4 Flashcards
What does connective tissue consist of?
mostly fibers and ground substance, with widely separated cells
Tendons bind…
muscle to bone
Ligaments bind…
bones together
What is the purpose of connective tissue?
binding to organs, support, physical protection, immune protection, movement, storage, heat production, and transport
How is connective tissue supportive?
cartilage supports other structures besides the body
Movement?
bones provide a lever system for movement; cartilage on bone surfaces eases joint movement
How is connective tissue used for storage?
fat is a connective tissue that forms the body’s major energy reserve
What kind of fat generates heat in infants and children?
brown fat
How does connective tissue transport?
blood is a connective tissue that transports gases, nutrients, wastes and other material
What is the most diverse type of connective tissue?
fibrous
What is fibrous connective tissue made of?
cellular and fibrous components in a ground substance
What are the six types of cellular components
fibroplasts, macrophages, leukocytes, plasma cells, mast cells, adipocytes
What is a fibroplast?
produce the fibers and ground substance of the tissue
What is a macrophage?
large phagocytic cells that engulf and destroy bacteria
What are plasma cells?
synthesize antibodies
What are mast cells?
near blood vessels secrete heparin and histamine
What are adipocytes?
fat cells that store triglycerides for feul
What are the three types of protein fibers in fibrous components?
collagenous, reticular, and elastic
What are collagenous fibers?
made of collagen and are tough, flexible, and resist stretching
What are reticular fibers?
thin collagen fibers coated with glycoprotein, forming a spongelike framework in some organs
What are elastic fibers?
made of elastin, which can recoil from stretching like a rubber band
What is ground substance?
occupies the space between cells and fibers and usually has gelatinous consistency because of proteoglycans and glycoproteins
What two categories are fibrous connective tissue divided into?
loose connective tissue and dense connective tissue
What is loose connective tissue?
much of the space is occupied by ground substance
What is dense connective tissue
fiber occupies more space than cells and ground substance
What is areolar tissue?
exhibits loosely organized fibers, abundant blood vessels, and a lot of empty space
What is reticular tissue?
a mesh of reticular fibers and fibroblasts forming the structural framework (stroma) of many organs
Why is dense regular connective tissue called that?
closely packed collagen fibers with little open space; and the parallel arrangement of fibers
What are the fibers in areolar tissue like?
randomly organized and mostly collagenous, although elastic and reticular fibers are present
Where is areolar tissue found?
underlying nearly all epithelia, including the skin and membranes of the body and surrounding blood vessels and nerves
Why are the fibers in dense regular connective tissue arranged the way they are?
it is an adaptation to directional pull, such as on tendons and ligaments
What kind of cells do dense regular connective tissue consist of?
fibroblasts
What is dense irregular connective tissue?
has closely packed collagen fibers, but the collagen bundles run in random directions
Why are the fibers arranged that way in dense irregular connective tissue?
random orientation allows resistance to unpredictable stresses
What is adipose tissue?
fat tissue in which adipocytes are dominant cell type
What is white fat?
more abundant and is the only significant fat tissue in adults
How big are adipocytes?
70 to 120 um in diameter but may be five times as large in obese people
What is the purpose of adipose tissue?
provides thermal insulation, anchoring, and cushioning
What is cartilage?
a supportive connective tissue with a flexible rubbery matrix
What are chondroblasts?
secrete and surround themselves with matrix until they are trapped in cavities called lacunae, at which time they are called chondrocytes
What is hyaline cartilage?
clear and glassy in microscopic appearance; the collagen fibers are very fine and invisible
What is elastic cartilage?
conspicuous elastic fibers
What is fibrocartilage?
has coarse, readily visible bundles of cartilage
Define bone
refers either to an organ such as the femur and mandible, composed of multiple tissue types, or to bone tissue (osseous tissue), which makes up most of the mass of the bones
What is spongy bone?
fills the heads of long bones and forms the middle layer of flat bones such as the sternum
What is compact (dense) bone?
a calcified tissue with no spaces visible to the naked eye
How is compact bone arranged?
in cylinders of tissue that surround central (haversian or osteonic) canals that run longitudinally through long bones?
What travels through the canals of bones?
blood and nerves
What is bone matrix composed of?
deposited in concentric lamellae around each central canal
What is an osteon?
a central and its surrounding lamellae
What are osteocytes?
between the lamellae are occupied by mature bone cells
What are canaliculi?
tiny canals radiate between lacunae allowing osteocytes to contact each other
What is the bone as a whole covered in?
fibrous periosteum
What is two-thirds of the weight of bone?
calcium salts deposited around the collagen fibers
