lecture 2.1

Question 1

what is the basement membrane

Answer 1

epithelium which attaches to the connective tissue

it is a semi permeable membrane
- nutrients
-gas exchange
-water transport

Question 2

what is connective tissue

Answer 2

it is support tissue
provides structure
strength
storage
transport
repair

it is vascular except for catrilage

examples are tendons, adipose tissue, bones, cartilage, blood

Question 3

What is connective tissue composed of and how is it derived

Answer 3

it is composed of cells and an extracellular matrix (made up of protein fibers and ground substances)

Derived from mesenchymal stem cell - embryological tissue where all types of connective/supporting tissue is derived

Question 4

what are the extracellular matrix fibers in connective tissue composed of

Answer 4

Collagen
Elastin
Reticulin

Question 5

What is collagen

Answer 5

-main fiber type in the ECM of connective tissue and most abundant protein
-secreted by fibroblasts
-there are 5 types of collagen (secreted as tropocollagen)
-eosinophilic

since it is so strong it has tensile strength and helps resist pulling, stretching and tearing

Question 6

what is elastin

Answer 6

fiber in ECM of connective tissue

-made up on tropoelastin
-is differentiated by collagen fibers using a special stain
-arranged as fibers or continuous sheets
-secreted as tropelastin

• stretch and recoil

found in lung, bladder, aorta, heart and skin

Question 7

what is reticulin

Answer 7

fiber in ECM of connective tissue

-it is a type lll collagen
-produced by fibroblasts
-found in hematopoietic and lymphatic tissue
- branching fibers
-found in stroma of lymphoid organs
-stain with silver stain only making them argyrophilic

• it is a works as a support fiber and provides a framework around cellular tissue

liver, spleen, bone marrow,

Question 8

what are the germ layers of connective tissue cells

Answer 8

Ectoderm
-nervous tissue, epidermis cells, and pigment cells,

Mesoderm
-muscle cells, skeleton, heart, kidney, blood

Endoderm
-endocrine glands, lungs, GI tract

Question 9

what types of cells come from undifferentiated mesenchymal cells?

Answer 9

embryological tissue where all types of connective/supporting tissue is derived

osteoblast, osteocyte
adipocyte
endothelial cells
mesothelial cells

Question 10

what type of cells come from hematopoietic stem cell

Answer 10

RBCs
Neutrophil
Eosinophil
basophil
b lymph

Question 11

what are fibro blasts (active with oval nuc) and fibrocytes (spindle shaped with flat nuc)

Answer 11

-they help to synthesize fibers and ground substance ( a gel made up of glycoproteins and carbs )
-they are the main cells in dense connective tissue

Question 12

structure of fibroblasts

Answer 12

-Active Connective tissue cells
-spindle shaped cells
-large oval nucleus
-they are the main cells in dense connective tissue

Question 13

structure of fibrocytes

Answer 13

-INactive Connective tissue cells
-spindle shaped cells
-small flat nucleus
-they are the main cells in dense connective tissue

Question 14

what are chondroblasts

Answer 14

-cells that are found in the cartilage tissue
-precursor cells that turn into chondrocytes
-active and secrete into the ECM around them
-found on the surface of the cartilage

Question 15

what are chondrocytes

Answer 15

-cells that are found the cartilage tissue
-inactive mature cells found in the lacunae
-surrounded by cartilaginous ECM

Question 16

what are the cells that make up bone tissue

Answer 16

osteoblast
osteocyte
osteoclast

Question 17

what is an osteoblast

Answer 17

-precursor cells that turns into osteocytes
-secret into the ECM around them
-found on the surface of the bone

forming/building

Question 18

what is an osteocyte

Answer 18

-inactive mature cell
-found in the lacunae
-surrounded by bony ECM

Question 19

what is an osteoclast

Answer 19

-large cells with many (10-15) nuclei
-secret acid phosphatase and enzymes to reabsorb old osteocytes
-maintain bone metabolism (breaking down/reabsorbing bone tissue)

Question 20

what are adipocytes and how many types are there

Answer 20

-fat cells that store lipid found in adipose connective tissue
-singly or in small clusters
-stain pale since lipid content is not preserved during staining and nuclei is compressed to one side of the cell

White adipose tissue - Adult used for energy storage, insulation, cushioning

Brown Adipose tissue - thermoregulation found in newborns and hibernating animals (lobules)

Question 21

what is endothelial cell

Answer 21

flat cells that line the endothelium (surface lining blood vessels and lymph vessels)

Question 22

what is a mesothelial cell

Answer 22

-flat cells that line the mesothelium (the membrane that covers the body cavities)

Question 23

during in inflammatory response what would you see in tissue

Answer 23

neutrophils, lymphocytes and plasma cells

Question 24

what would you see in the tissue as a response to an allergic reaction

Answer 24

eosinophils with orange granules

Question 25

what is job of RBC

Answer 25

-erythrocytes -contain red pigment called hemoglobin - deliver O2 to tissues and release CO2 from your lungs

Question 26

what are macrophages and which tissue types do they exist in

Answer 26

-phagocytes - destruction of bacteria -Kupffer cells of liver -alveolar macrophage - lungs -microglia - CNS -Langerhans cells -skin

Question 27

what is a mast cell and where is a found

Answer 27

-responds to antigen- antibody reactions -anaphylaxis -secretes heparin and histamine from cytoplasm

Question 28

what are plasma cells

Answer 28

-derived from b lymph -secretion of AB to provide humoral immunity -cytoplasm is eosinophilic

Question 29

what are the two types of connective tissues and what are they composed of

Answer 29

-Classification is based on fiber orientation -this is how the CT is morphologically described *Connective tissue proper (dense) -loose (aerolar) ordinary -adipose, reticular -dense regular -dense irregular *Specialized connective tissue -supporting connective tissue: bone and cartilage -fluid connective tissue :blood

Question 30

What is LOCT

Answer 30

-Loose ordinary CT (aerolar) -found in loose wavey fibers -flimsy collagen fibers -cellular with alot of matrix -vascular -support, strength, elasticity -found in deep layers of skin, around blood vessels, organs example is LAMINA PROPRIA - GI tract with lots of WBC

Question 31

what is adipose CT

Answer 31

- LOCT -made up of adipocytes in lobules where the nuclei and cytoplasm are located peripherally -functions in energy storage and insulation -found in hypodermis , kidneys, heart

Question 32

what is reticular CT

Answer 32

- LOCT -like net with loosely arranged cells -found in stroma (framework) of hematopoietic tissue (bone marrow) and lymphoid organs (spleen, lymph nodes) -functions to form stromas, binds smooth muscle cells, filters out old cells in the spleen and microbes in the lymph nodes)

Question 33

what is DRCT

Answer 33

-regular dense connective tissue -mostly fibroblasts/cytes so basically collagen fibers packed into bundles -muscle contraction -found in muscles and ligaments poor vascularization

Question 34

what is DICT

Answer 34

-dense irregular ct -collagen fibers in an interlacing pattern -stand tension -found in places that experience stretching like skin, fibrous capsule of organs and joints

Question 35

what type of CT is bone

Answer 35

-specialized connective tissue specifically supporting connective tissue -also known as osseous tissue -consists of osteocytes -found in skeletal system -functions in support, joint movement , protection, CA/PO4 reservoir -there are compact and cancellous (spongy) bones

Question 36

what type of CT is cartilage

Answer 36

-specialized connective tissue specifically supporting connective tissue -composed of CHONDRO AND ECM -avascular -hyaline, elastic, fibrocartilage

Question 37

what is hyaline cartilage

Answer 37

-most abundant type of cartilage -blueish white with a shiny background -provides smooth surface for movement at joints -found at the end of long bones , nose, fetal skeleton

Question 38

what is elastic cartilage

Answer 38

-made up of CHONDRO, collagen and elastin -provides flexibility and support -epiglottis, external ear, laryngeal

Question 39

what is fibrocartilage

Answer 39

-made up of CHONDRO and dense CT -attachment near tendon or ligament -provide tensile strength

Question 40

what type of CT is blood

Answer 40

-specialized connective tissue specifically fluid connective tissue -contains plasma ground substance + RBCs + WBCs + platelets