connective tissue

Question 1

what is c.t.?

Answer 1

tissue that holds other tissues together to give the body its form and has a supportive function

Question 2

what is c.t. composed of?

Answer 2

cells called fibroblasts, fibers produced by these cells, and ground substance or extracellular matrix

Question 3

what are the four basic types of c.t.?

Answer 3

Connective tissue proper
Blood
Bone
Cartilage

Question 4

what are the two categories of c.t. proper?

Answer 4

dense c.t.
loose c.t.

Question 5

what is loose c.t.?

Answer 5

• loose filmy to gelatinous material that is present in tissues.
• mostly irregular with random distribution of fibroblasts and loosely packed fibers weaving in and out of the c.t.

Question 6

what is dense c.t.?

Answer 6

tougher and is found as protective sheaths, and also makes up ligaments and tendons.

Question 7

what is dense regular c.t. and examples

Answer 7

fibers are packed tightly together and have the same orientation
ex. tendons and ligaments

Question 8

what is dense irregular c.t. and examples?

Answer 8

random fibers and cells, but they are packed tightly together giving it a thick fabric-like appearance.
ex. Tough connective tissue sheaths and capsules of organs

Question 9

what is the predominant cell type of c.t.?

Answer 9

fibroblasts

Question 10

describe the appearance of fibroblasts

Answer 10

fusiform with an elongated nucleus

Question 11

what do fibroblasts produce?

Answer 11

collagen fibers

Question 12

what type of cell is predominant in embryonic tissue, are stellate, and are pluripotent?

Answer 12

mesenchymal cell

Question 13

what are reticular cells

Answer 13

present in organs and provide a framework or scaffold for certain cells

Question 14

give an example of where reticular cells are present and what they produce

Answer 14

lymph nodes, where they produce reticular fibers and provide a scaffold for lymphocytes to populate the lymph node

Question 15

where are adipocytes found and why?

Answer 15

found in loose connective tissue and in adipose tissue that serves as a padding under the skin or around organs

Question 16

which cell type has a signet ring?

Answer 16

adipocytes

Question 17

list the inflammatory cells that migrate to c.t.

Answer 17

histiocytes, mast cells, lymphocytes, eosinophils, macrophages and plasma cells

Question 18

describe type I collagen

Answer 18

• most predominant, 90% of c.t.
• coarse fibers: produced by fibroblasts but also smooth muscle cells and osteoblasts

Question 19

describe type II collagen (fine collagen)

Answer 19

• found in cartilage, nucleus of pulposus of intervertebral disc, and vitreous humor of eye
• can’t see it

Question 20

describe type III collagen (reticular fibers)

Answer 20

• produced by reticular cells, fibroblasts, smooth muscle cells
• found in lymphoid organs and skin
• visualized with silver strain

Question 21

describe type IV collagen (lattice fibers)

Answer 21

• forms lattice on which epithelial cells rest
• makes up basement membrane for epithelial surfaces

Question 22

where are elastic fibers found?

Answer 22

bvs and elastic cartilage

Question 23

what are elastic fibers synthesized by?

Answer 23

fibroblasts, smooth muscle cells, and chondroblasts

Question 24

what are ground substances made of?

Answer 24

glycosaminoglycans (GAGs) and proteoglycans

Question 25

what is the purpose of ground substance?

Answer 25

- retain water and help with nutrient transfer - important for tissue repair and regeneration

Question 26

true or false: you can't see ground substance in a stain

Answer 26

true

Question 27

true or false: muscle is a type of c.t.

Answer 27

false

Question 28

muscle account for what percentage of body mass?

Answer 28

70%

Question 29

what are the 3 basic types of muscle?

Answer 29

- skeletal - smooth - cardiac

Question 30

what is the purpose of skeletal muscle?

Answer 30

- making the body move - provides shape - plays important role in physiological function like metabolism, thermogenesis, and maintaining electrolyte balance

Question 31

what is the purpose of smooth muscle?

Answer 31

- forms protective covering for internal organs and helps in their motility - helps with storing body fluid and ingesta, digestion and respiration - helps maintain blood pressure - facilitates movement of blood throughout body

Question 32

what is cardiac muscle responsible for?

Answer 32

supplying blood to and from different parts of body

Question 33

what is the most abundant type of muscle in body?

Answer 33

skeletal

Question 34

Each muscle is made up of individual muscle cells or ________

Answer 34

myofibers

Question 35

Each muscle cell or myofiber is made up of numerous _________

Answer 35

myofibrils

Question 36

Each myofibril is made up of ___________ stacked on top of each other

Answer 36

sarcomeres

Question 37

Each sarcomere is made up of myofilaments, what are myofilaments composed of?

Answer 37

actin, myosin, troponin, tropomyosin

Question 38

what gives muscle its striated appearance?

Answer 38

actin and myosin filament arrangement within the sarcomere

Question 39

The nuclei of the myofibers are always located in the ____________

Answer 39

periphery

Question 40

what can skeletal muscle be identified by?

Answer 40

- striations - peripherally located nuclei

Question 41

true or false: skeletal muscle is placed under involuntary control

Answer 41

false: voluntary

Question 42

describe the muscle fiber of smooth muscle

Answer 42

short, fusiform, tightly packed

Question 43

why is the smooth muscle in the gut arranged as an inner circular and outer longitudinal layer?

Answer 43

helps peristalsis

Question 44

why are striations not visible in smooth muscle?

Answer 44

myofilaments are oriented along the axis of the cell

Question 45

why are there gap junctions between cells of smooth muscle?

Answer 45

to facilitate quick and coordinated contraction

Question 46

how can smooth muscle be identified?

Answer 46

Lack of striations Short length Centrally placed nuclei

Question 47

why is cardiac muscle unique?

Answer 47

it is not only under autonomic control, but has its own rhythm of contraction

Question 48

how can cardiac muscle be identified?

Answer 48

- striations - centrally placed nuclei - branched - intercalated discs