Lecture 16- Connective Tissue and Muscle

Question 1

A tissue type of cells embedded in extracellular matrix, NOT muscle, epithelial, or nervous tissue

Answer 1

Connective tissue

Question 2

What type of cells make the extracellular matrix?

Answer 2

Fibroblasts

Question 3

What are the two parts of the ECM

Answer 3

fibers and ground substance

Question 4

What are myofibroblasts

Answer 4

Activated fibroblasts that promote healing

Question 5

What are two types of fibers found in the ECM?

Answer 5

Collagen and ellastin

Question 6

What is the main quality of collagen?

Answer 6

Tensile strength

Question 7

Where is type I collagen found?

Answer 7

fibrous supporting tissues (bone, ligaments, skin, and tendons)

Question 8

Where is Type II collagen found?

Answer 8

Hyaline cartilage

Question 9

What is another name of Type III collagen?

Answer 9

Reticulin

Question 10

Where is Type III collagen found?

Answer 10

supporting network for fleshy organs

Question 11

Where is Type IV collagen found?

Answer 11

basement membranes

Question 12

What is the main job of elastin?

Answer 12

Bounce, stretch, and recoil

Question 13

Where is elastin found?

Answer 13

Skin, bid arteries, bladder, nuchal ligament, external ear, vocal cords

Question 14

What is ground substance?

Answer 14

A gel-like substance surrounding fibroblasts

Question 15

What does ground substance do?

Answer 15

Protects from compression and allows nutrient/waste transport

Question 16

Structure of ground substance

Answer 16

Hyaluronic acid network to attract water
Proteoglycan limbs to add volume
Glycosaminoglycan branches to bind the ECM together

Question 17

Types of connective tissue

Answer 17

Loose
Dense (regular/irregular)
reticular
Elastic
Adipose
Bone

Question 18

Loose connective tissue composition and location

Answer 18

Lots of ground substance, few collagen fibers.
Found surrounding vessels and nerves.

Question 19

Dense irregular connective tissue composition and location

Answer 19

Lots of irregularly arranged collagen fibers, few cells.
Found in the dermis and submucosa of intestines

Question 20

Dense regualar connective tissue composition and location

Answer 20

Lots of parallel collagen fibers, few cells and ground substance
Located in tendons, ligaments, and aponeuroses

Question 21

Reticular connective tissue composition and location

Answer 21

Meshwork of reticulin, few cells
Found supporting cells in parenchymal organs

Question 22

Elastic connective tissue composition and location

Answer 22

Lots of elastin
Found in arteries, nuchal ligament, vocal cords…

Question 23

Adipose tissue composition and location

Answer 23

Adipocytes, with either a clear signet-ring shape (white) or multilocular droplets with central nuclei (brown)
Found everywhere

Question 24

Name of muscle cells

Answer 24

Muscle fibers/myofibers/myocytes

Question 25

Order of muscles

Answer 25

Muscle –> fascicles –> myofibers –> myofibryls –> filaments –> sarcomeres

Question 26

Where are nuclei located in myofibers?

Answer 26

Many nuclei per cell, located peripherally

Question 27

What is the myofiber cell membrane called?

Answer 27

Sarcolemma

Question 28

What are the borders of the sarcomeres?

Answer 28

Z discs

Question 29

What is the name of dark bands and what are they made of?

Answer 29

A bands
myosin

Question 30

What is the name of light bands and what are they made of?

Answer 30

I bands
Actin

Question 31

In what species does cardiac muscle also line the pulmonary veins?

Answer 31

Rodents

Question 32

Low electrical resistance between cardiomyocytes is due to-

Answer 32

Intercalated discs

Question 33

What is the difference between cardiac and skeletal muscle on microscopy?

Answer 33

Cardiac has branching, intercalated discs, more cytoplasm, and centrally located nuclei

Question 34

Why doesn’t smooth muscle have striations?

Answer 34

Actin and myosin crisscross instead of forming parallel lines