Lab Three

Question 1

what are the pink fibers in connective tissue proper?

Answer 1

collagen

Question 2

what is the arrangement of collagen fibers in loose (areola) connective tissue proper?

Answer 2

thick bundles of fibers running in all directions

Question 3

what are the black fibers in connective tissue proper?

Answer 3

elastin

Question 4

what is the arrangement of elastin in loose (areola) connective tissue proper?

Answer 4

finer branching fibers

Question 5

what is the shape of a fibroblast?

Answer 5

flattened cell

Question 6

what is the function of fibroblasts?

Answer 6

secrete both the ground substance and the fibres of the extracellular matrix

Question 7

what are the things that fibroblasts secrete?

Answer 7

collagen
elastin
reticular fibers
ground substance (cell adhesions proteins, proteoglycans)

Question 8

what does ground substance contain?

Answer 8

cell adhesion proteins
proteoglycans

Question 9

what is a prominent organelle in fibroblasts and why?

Answer 9

Rough endoplasmic reticulum. Fibroblasts manufature lots of proteins to secrete, which are synthesised by the RER

Question 10

what are the types of connective tissue proper?

Answer 10

loose (areola)
dense (collagenous)
elastic
reticular

Question 11

what is the arrangment of fibers in dense regular conective tissue?

Answer 11

collagen fibers run in thick parallel bundles and provide great tensile strength when a pulling force is applied in one direction

very few elastin fibres

Question 12

where is dense regular connective tissue found in the body?

Answer 12

present in tendons, most ligamnets and aponeuroses

Question 13

what is aponeruroses?

Answer 13

a fibrous or membranous sheet connecting a muscle and the part it moves

Question 14

what does baking bone do to the structure?

Answer 14

baking denatures the protein, therefore the collagen is destroyed, removing the tensile strength and the bone becomes brittle

Question 15

what does vinegar to do bone structure?

Answer 15

Calcium salts are dissolved in the vinigar thus making the matrix less rigid, and ‘bendy’

Question 16

what are the features of Dense connective tissue extracellular matrix?

Answer 16

-densely packed parallel collagen fibers, and a few elastin fibers

therefore in withstands tensile stress when pulled in one direction

Question 17

what are the features of Hyaline cartilage extra cellular matrix?

Answer 17

Collagen fibres present but form amorphous matrix, Chondroytes lie in lacunae

Therefore resists compressive stress, because it is firm but flexible

Question 18

what is the feature of a bone extracellular matrix?

Answer 18

Hard calcified matrix

Osteocytes lie in lacunae within the matrix

Therefore the bone supports, protects and acts as a level

Question 19

what are the features of adipose tissue extra cellular matrix?

Answer 19

Sparce matrix containing a lot of adipocytes filled with large lipid droplets

Therefore is a food reserve, supports and insulates

Question 20

what are the three types of muscle?

Answer 20

Skeletal (straited) muscle
Smooth muscle
Cardiac muscle

Question 21

where do bundles of connective filaments connect to the smooth muscle cells?

Answer 21

at the focal densities

Question 22

what is a supporting tissue?

Answer 22

connective tissue that provides protection to muscle fibers

Question 23

how many cells make up one muscle fiber?

Answer 23

One skeletal muscle cell = one muscle fiber

Question 24

how many nuclei are found in each skeletal muscle cell?

Answer 24

Many nuclei, varies between cells

Question 25

what are the features of a sarcomere?

Answer 25

the sarcomere is from one Z line to the next and contains overlapping thick filaments (A band) and the thin filaments (I band)

Question 26

what are thin filaments of the sarcomere made from?

Answer 26

actin

Question 27

what are the thick filaments in the sarcomere made from?

Answer 27

myosin

Question 28

what happens when the sarcomere contracts?

Answer 28

the thin and thick filaments slide over each other. The A band stays constant, the I band narrows and the Z lines are pulled closer together.

Question 29

what junctions form intercollated disks in cardiac muscle?

Answer 29

Fasia adherens- actin filaments insert into the z lines) Desmosomes (anchoring points for intermediate filaments) Gap junctions

Question 30

where do actin filaments inside cardiac muscle cells insert into to transmit contractile force?

Answer 30

into the z lines at the fascia adherens

Question 31

how does excitation spread within cardiac muscle cells?

Answer 31

through gap junctions

Question 32

what is the role of swann cells?

Answer 32

Myelinate insulated nerves

Question 33

what is the benefit to myelinated nerves?

Answer 33

Get less dissipation of excitation Speeds up transmission of AP

Question 34

what is the disadvangated to nerve myelination?

Answer 34

Myelination must be absent as dendrites for activation

Question 35

what strictures in a CNS neruon reflect a high metabolic activity?

Answer 35

Mitochondria Golgi Bodies Ribosomes (RER) Nucleolus

Question 36

what is the hypodermins?

Answer 36

a layer of tissue immediately inferior to the dermins that is not part of the skin (has a supporting role) Comprised of adipose tissue

Question 37

what are the cells within the stratum corneum?

Answer 37

dead flattened keratinised cells

Question 38

what are the cells of the epidermis?

Answer 38

Stratified squamous epithelium

Question 39

what are the cells of the stratum lucidum?

Answer 39

cells have no nuclei or organelles

Question 40

what are the cells of the stratum granulosum?

Answer 40

contain keratohyalin granules

Question 41

what are the cells of the stratum spinosum?

Answer 41

Keratinocytes held together by desmosomes (prickle cells)

Question 42

what are the cells of the stratum basale?

Answer 42

1 layer of cuboidal cells, many hemidesmosomes and desmosomes mitotic figures