Lecture 3: Connective Tissue Flashcards
(38 cards)
Overview
- widely distributed in the body
- cells are not stacked tightly, they are spaced well apart
- supporting tissue composed of cells embedded within a matrix that varies in consistency from fluid to crystals
- cells are responsible for synthesis and maintenance of the extracellular fluid
examples: cartilage, bone, ligaments, blood, and adipose tissue
connective tissue subtypes: 3 types
structural, defensive, and sequestering
structural connective tissue
fibroblast, cartilage, bone
defensive connective tissue
macrophages, lymphocytes
sequestering connective tissue
adipose tissue, red blood cells
fibroblasts
most common connective tissue within vertebrate bodies
flat, irregular, branching cells
secretes structurally strong proteins into matrix between cells; most commonly COLLAGEN
-fibroblasts also secrete elastin
Elastin
fibrous tissue that is the principal component of the lungs
Areolar (loose) Connective Tissue (ACT)
- found throughout the body wherever protective cushioning and flexibility are needed
- ie. blood vessels are surrounded by a sheath of ACT; permits the vessels to move and yet protects them
- also present beneath the skin, attaching it to underlying muscles
Dense Regular CT
present in tendons, connecting muscle to bone, and in ligaments, connecting bone to bone
Dense Irregular CT
present in dermis (living part) of the skin
- arranged in thick mat
- tanned to make leather, also present in arterial walls
Cartilage: 3 types
firmer and flexible tissue that does not stretch, yet not as hard as bone
- laid down along lines of stress; cells=chondrocytes
- 3 types: hyaline, elastic, and fibrocartilage
hyaline cartilage
- glass-like covering of bones within joints
- forms a smooth surface that reduces friction so one bone easily glides over another
- found at ends of long bones
elastic cartilage
mixture of cartilage substances and elastic fibers
-found in external ear
fibrocartilage
cartilage and collagen
-interverteral discs are made of fibrocartilage
Bone
special form of cartilage where the collagen fibers are coated with a calcium phosphate salt
-bone forming cells are osteoblasts and osteoid tissue, that calcify to form bone
harvesian canals
channels surrounded by lamellae, which contain blood vessels and nerve cells
lamellae
bone laid down in concentric layer
spongy or cancellous bone
lines the medullary cavity
compact bone
surrounds the spongy bone and collagen fibers are laid down in a pattern far denser than the interior framework
Blood
connective tissue consisting of microscopically visible elements: erythrocytes, leukocytes, and platelets/thrombocytes, all suspended in intercellular fluid called plasma
plasma>erythrocytes>leukocytes
plasma
complex fluid in which blood cells and thrombocytes circulate
- 93% water, 7% solutes, including proteins, inorganic solutes, nonprotein oranic substances (glucose, glycerol, and fatty acids)
- hormones, enzymes, vitamins, and pigments
- cell waste products (urea, uric acid)
- amino acids
serum
supernatant yellow fluid that is expressed out when blood coagulates
-serum is used for prevention and treatment of diseases because it contains the antibody fraction of the blood
Blood cell types
red blood cells/erythrocytes, white blood cells/leukoccytes, and platelets/thrombocytes
RBC
transport gases
- flat discs with a central depression
- contain pigment called hemoglobin, which associates and dissociates with O2 and CO2