chapter 4 - Tissue Level - PART 2

Question 1

What are the 6 functions of connective tissue?

Answer 1

1) bind together, support, and strengthen other body tissues
2) protect and insulate internal organs
3) compartmentalize structures such as skeletal muscles
4) serve as the major transport system within the body (blood, a fluid connective tissue
5) primary locations of stored energy reserves (adipose, or fat, tissue);
6) main source of immune responses

Question 2

what are the 3 general components of connective tissue?

Answer 2

cells, ground substance and protein fibres.

Question 3

What are blast cells?

Answer 3

retain the capacity for cell division and secrete the extracellular matrix that is characteristic of the tissue

Question 4

What are fibroblasts?

Answer 4

• large, flat cells with branching processes.
• present in all the general connective tissues, and most numerous.
• migrate through the connective tissues, secreting the fibers and certain components of the ground substance of the extracellular matrix.

Question 5

List the 7 different cells in connective tissue

Answer 5

Blast cells, fibroblasts, macrophages, plasma cells, mast cells,adipocytes, WBC,

Question 6

What are macrophages?

Answer 6

• irregular shape with short branching projections

• engulfing bacteria and cellular debris by phagocytosis.
• move throughout the tissue and gather at sites of infection or inflammation to carry on phagocytosis

Question 7

What are plasma cells

Answer 7

• secrete antibodies (proteins that attack or neutralize foreign substances in the body) = part of the body’s immune response.
- especially in the gastrointestinal and respiratory tracts. They are also abundant in the salivary glands, lymph nodes, spleen, and red bone marrow.

Question 8

What are mast cells?

Answer 8

• produce histamine (dilates small blood vessels in response to injury/infection)
• bind to, ingest, and kill bacteria
  abundant alongside the blood vessels that sup- ply connective tissue

Question 9

what are adipocytes?

Answer 9

• store triglycerides (fats).

- found deep to the skin and around organs such as the heart and kidneys

Question 10

What are white blood cells

Answer 10

migrate from blood into connective tissues

Question 11

What is the ground substance?

Answer 11

• between the cells and fibers.

• may be fluid, semifluid, gelatinous, or calcified.
• supports cells, binds them together, stores water, and provides a medium for exchange of substances between the blood and cells.
• plays an active role in how tissues develop, migrate, proliferate, and change shape, and in how they carry out their metabolic functions.

Question 12

What are the 3 types of fibers in connective tissue?

Answer 12

1) Collagen fibers: strong and resist tension
- not stiff = tissue flexibility.
- often occur in parallel bundles = tensile strength
- consist of the protein collagen.
- found in bone, cartilage, tendons and ligaments
2) Elastic fibers (smaller in diameter than collagen)
- form a fibrous network
- consists of protein elastin surrounded by a glycoprotein named fibrillin (adds strength and stability).
- return to their original shape after being stretched
- plentiful in skin, blood vessel walls, and lung tissue.
3) Reticular fibers,
- provide support in the walls of blood vessels
- much thinner than collagen fibers and form branching networks = support and strength.
- plentiful in reticular connective tissue, which forms the stroma/framework of many soft organs, such as the spleen and lymph nodes.

Question 13

Describe loose connective tissue. What are the 3 types?

Answer 13

> The fibers of loose connective tissues are loosely arranged between cells.

1) areolar connective tissue
2) adipose tissue
3) reticular connective tissue

Question 14

describe the structure, function and location of Areolar connective tissue

Answer 14

o Structure: consists of fibers (collagen, elastic, reticular) arranged randomly and several kinds of cells embedded in semifluid ground substance
o Location
♣ nearly every body structure (thus, called “packing material” of the body): in subcutaneous layer deep to skin; papillary (superficial) region of dermis of skin; lamina propria of mucous membranes; around blood vessels, nerves, and body organs.
♣ Function: Strength, elasticity, support.

Question 15

describe the structure, function and location of adiposetissue

Answer 15

o specialized for storage of triglycerides (fats) as a large, centrally located droplet. Cell fills up with a single, large triglyceride droplet, and cytoplasm and nucleus are pushed to periphery of cell.
o Location: Wherever areolar connective tissue is located: subcutaneous layer deep to skin, around heart and kidneys, yellow bone marrow, padding around joints and behind eyeball in eye socket.
♣ Function: Reduces heat loss through skin; serves as an energy reserve; supports and protects organs. In newborns, brown adipose tissue (BAT) generates heat to maintain proper body temperature.

Question 16

describe the structure, function and location of reticular connective tissue

Answer 16

• Fine interlacing network of reticular fibers (thin form of collagen fiber) and reticular cells.
o location : Stroma of liver, spleen, lymph nodes; red bone marrow; reticular lamina of basement membrane; around blood vessels and muscles.
♣ Function: Forms stroma of organs; binds smooth muscle tissue cells; filters and removes worn-out blood cells in spleen and microbes in lymph nodes.

Question 17

What are the types of dense connective tissue

Answer 17

1) dense regular connective tissue
2) dense irregular connective tissue
3) elastic connective tissue

Question 18

describe the structure, function and location of dense regular connective tissue

Answer 18

• structure: mainly collagen fibers regularly arranged in bundles with fibroblasts in rows between bundles.
o Location: Forms tendons, ligaments and aponeuroses (sheetlike tendons that attach muscle to muscle or muscle to bone).
♣ Function: Provides strong attachment between various structures. Tissue structure withstands pulling (tension) r

Question 19

describe the structure, function and location of dense irregular connective tissue

Answer 19

o collagen fibers; usually irregularly arranged with a few fibroblasts.
o Location : fasciae (tissue beneath skin and around muscles and other organs), reticular (deeper) region of dermis of skin, fibrous pericardium of heart, periosteum of bone, perichondrium of cartilage, joint capsules, membrane capsules around various organs (kidneys, liver, testes, lymph nodes); also in heart valves.
♣ Function: Provides tensile (pulling) strength in many directions

Question 20

describe the structure, function and location of elastic connective tissue

Answer 20

o Predominantly elastic fibers with fibroblasts between fibers;
o Location: Lung tissue, walls of elastic arteries, trachea, bronchial tubes, true vocal cords, suspensory ligaments of penis, some ligaments between vertebrae.
♣ Function: Allows stretching of various organs; Elasticity is important to functioning of lung tissue (recoils in exhaling) and elastic arteries (recoil between heartbeats to help maintain blood flow).

Question 21

What are the 4 different types of cartilage?

Answer 21

chondrocytes
hyaline cartilage
fibrocartilage
elastic cartilage

Question 22

• The cells of mature cartilage, called _______ occur singly or in groups within spaces called lacunae in the extracellular matrix

Answer 22

chondrocytes

Question 23

describe the structure, function and location of Hyaline cartilage

Answer 23

o contains a resilient gel as ground substance. Fine collagen fibers
o Location: Most abundant cartilage in body; at ends of long bones, anterior ends of ribs, nose, parts of larynx, trachea, bronchi, bronchial tubes, embryonic and fetal skeleton.
♣ Function: Provides smooth surfaces for movement at joints, flexibility, and support; weakest type of cartilage.

Question 24

describe the structure, function and location of fibrocartilage

Answer 24

• Chondrocytes scattered among thick bundles of collagen fibers within extracellular matrix; lacks perichondrium
o Location : Pubic symphysis, intervertebral discs, menisci of knee, portions of tendons that insert into cartilage.
♣ Function: Support and joining structures together. Strength and rigidity make it the strongest type of cartilage.

Question 25

describe the structure, function and location of elastic cartilage

Answer 25

o Chondrocytes in threadlike network of elastic fibers within extracellular matrix; perichondrium present.
o Location: epiglottis, part of external ear (auricle), auditory (eustachian) tubes.
♣ Function: Provides strength and elasticity; maintains shape of certain structures.
bone tissue or osseous tissue

Question 26

The basic unit of compact bone is an ______ or _________

Answer 26

osteon or haversian system

Question 27

What are the 5 parts of each osteon?

Answer 27

o Thelamellaeare concentric rings of extracellular matrix that consist of mineral salts
o Lacunaeare small spaces between lamellae that contain mature bone cells called osteocytes.
o canaliculinetworks of minute canals Projecting from the lacunae - provide routes for nutrients and wastes
o A central (haversian) canal contains blood vessels and nerves.
o columns of bone called trabeculae- Spaces between trabeculae are filled with red bone marrow.

Question 28

What is the structure, function and location of osteons (haversian systems)

Answer 28

♣ Compact bone tissue consists of osteons (haversian systems) that contain lamellae, lacunae, osteocytes, canaliculi, and central (haversian) canals. By contrast, spongy bone tissue consists of thin columns called trabeculae; spaces between trabeculae are filled with red bone marrow.
♣ LOCATION: Both compact and spongy bone tissue make up the various parts of bones of the body.
♣ FUNCTION: Support, protection, storage; houses blood-forming tissue; serves as levers that act with muscle tissue to enable movement.

Question 29

What is the structure, function and location of blood tissue

Answer 29

• Structure: connective tissue with a liquid extracellular matrix and formed elements. The extracellular matrix is called blood plasma
oLOCATION: Within blood vessels (arteries, arterioles, capillaries, venules, veins), within chambers of heart.
♣ FUNCTION: Red blood cells: transport oxygen and some carbon dioxide; white blood cells: carry on phagocytosis and mediate allergic reactions and immune system responses; platelets: essential for blood clotting.

Question 30

Describe the 4 types of blood tissue?

Answer 30

Plasma
• The blood plasma is a pale yellow fluid that consists mostly of water with a wide vari- ety of dissolved substances—nutrients, wastes, enzymes, plasma proteins, hormones, respiratory gases, and ions. Suspended in the blood plasma are formed elements—red blood cells (erythro- cytes), white blood cells (leukocytes), and platelets
red blood cells
• Red blood cells transport oxygen to body cells and remove some carbon dioxide from them.
white blood cells
• White blood cells are involved in phagocytosis, immunity, and allergic reactions.
Platelets
• Platelets participate in blood clotting

Question 31

What is lymph?

Answer 31

• Lymph is the extracellular fluid that flows in lymphatic vessels. It is a connective tissue that consists of several types of cells in a clear liquid extracellular matrix that is similar to blood plasma but with much less protein.

Question 32

Define the term membrane

Answer 32

Membranesare flat sheets of pliable tissue that cover or line a part of the body.

Question 33

What is a mucous membrane or muscosa

Answer 33

• A mucous membrane or mucosa lines a body cavity that opens directly to the exterior. Mucous membranes line the entire digestive, respiratory, and reproductive tracts, and much of the urinary tract. They consist of a lining layer of epithelium and an underlying layer of connective tissue

Question 34

What is serous membrane or serosa

Answer 34

• A serous membrane or serosa lines a body cavity that does not open directly to the exterior (thoracic or abdominal cavities), and it covers the organs that are within the cavity. Serous membranes consist of areolar connective tissue covered by mesothelium (simple squamous epithelium)

Question 35

What is a cutaneous membrane or skin

Answer 35

• The cutaneous membrane or skin covers the entire surface of the body and consists of a superficial portion called the epidermis and a deeper portion called the dermis

Question 36

WHat is a synovial membrane

Answer 36

• Synovial membranes line the cavities of freely movable joints (joint cavities). Like serous membranes, synovial membranes line structures that do not open to the exterior. Unlike mucous, serous, and cutaneous membranes, they lack an epithelium and are therefore not epithe- lial membranes
compare the structure, location

Question 37

What are the 3 types of muscle tissue?

Answer 37

Skeletal muscle tissue, Cardiac muscle tissue, Smooth muscle tissue

Question 38

What is the structure, function and location of skeletal muscle tissue

Answer 38

o Long, cylindrical, striated fibers (alternating light and dark bands). A muscle fiber is a roughly cylindrical, multinucleated cell with nuclei at periphery.
o LOCATION
♣ Usually attached to bones by tendons.
♣ FUNCTION
Motion, posture, heat production, protection.

Question 39

What is the structure, function and location of cardiac muscle tissue

Answer 39

• Structure: Branched, striated fibers with usually only one centrally located nucleus (occasionally two). Attach end to end by transverse thickenings of plasma membrane called intercalated discs
  ♣ Location: Heart wall.
  ♣ Function: Pumps blood to all parts of body.

Question 40

What is the structure, function and location of smooth muscle tissue

Answer 40

♣ Structure: Fibers usually involuntary, nonstriated (lack striations). small spindle-shaped cell thickest in middle, tapering at each end, and containing a single, centrally located nucleus.
♣ Location: Iris of eyes; walls of hollow internal structures such as blood vessels, airways to lungs, stomach, intestines, gallbladder, urinary bladder, and uterus.
♣ Function: Motion (constriction of blood vessels and airways, propulsion of foods through gastrointestinal tract, contraction of urinary bladder and gallbladder).

Question 41

describe the structural features and functions of nervous tissue.

Answer 41

•1) Neurons (nerve cells), which consist of cell body and processes extending from cell body (one to multiple dendrites and a single axon); and (2) neuroglia, which do not generate or conduct nerve impulses but have other important supporting functions.
o Location: Nervous system.
♣ Function: Exhibits sensitivity to various types of stimuli; converts stimuli into nerve impulses (action potentials); conducts nerve impulses to other neurons, muscle fibers, or glands.

Question 42

describe generally, and give examples of, homeostatic imbalances in tissues.

Answer 42

• The most prevalent disorders of connective tissues are autoim- mune diseases—diseases in which antibodies produced by the immune system fail to distinguish what is foreign from what is self and attack the body’s own tissues. One of the most common autoim- mune disorders is rheumatoid arthritis, which attacks the synovial membranes of joints.
• Sjögren’s syndrome (SHO-grenz) is a common autoimmune disor- der in which your own immune system attacks the lacrimal (tear) glands and salivary glands, especially, and causes inflammation and destruction of these exocrine glands. Signs include dryness of the eyes, mouth, nose, ears, skin, and vagina, and salivary gland enlargement.
• Systemic lupus erythematosus or simply lupus, is a chronic inflammatory disease of connective tissue occur- ring mostly in nonwhite women during their childbearing years. It is an autoimmune disease that can cause tissue damage in every body system.