Histology Quiz 3

What fiber is seen here in H&E?

What fiber is seen here in silver stain?

What fiber is seen here in Verhoeff’s stain?

What type of CT proper? Where could it be found?

What type of CT proper? Where could it be found?

What type of CT proper? Where could it be found?

Which tissues do you think might be most affected by mutations in the Collagen I gene?

What is the function of connective tissue?

mix of proteins secreted by cells into extracellular environment that can form meshes, gels or hard crystals

In many connective tissues, the ____ becomes more abundant than the _____ themselves

what is ecm composed of?

• More heavily glycosylated

• Variety of carbs and glycosylated proteins

• Structure with more flexibility

• Hydrated and gel like-> important for nutrient/waste exchange

• Mediates movement of molecules and cells as well as cellular adhesion

what are the 2 types of fibers

Component of ecm that provides strength, structure, support, and sometimes flexibility

-most abundant protein in body at 30% of dry weight

• Very strong-> resistant to tearing

• Self assemble outside of cell to form bundles of fibers or mesh like sheets

large collagen fibers, very acidophilic in H&E

very delicate collagen fibers (supports highly cellular environments), not visible w/ H&E use silver stain

• Flexible, found in tissues that need to stretch

  • Musculature, arteries ect

• Don’t stain well w/ H&E (Verhoeff’s often used)

  • Usually squiggly bc tissue is relaxed

• Primarily composed of cells called fibroblasts

  • Embedded in surrounding ECM

  • Produce and secrete the extensive ECM

actively producing ECM and have enlarges nuclei w/ well developed RER and golgi

\n Fibroblasts of mature CT are typically _____ and thus have condensed ___ and minimal ________

highly cellular; abundant ground substance in ECM; ECM fibers less abundant and scattered (no bundles, may include both collagen and elastin)

less cellular; abundant fibers in ECM (mostly collagen I/II), often bundled but not well organized

ECM is abundant and packed densely with parallel arrays of protein fibers (collagen I/II); cells are sparse and squeezed in between fibers of the ECM

What types of collagen are found in loose CT?

What types of collagen are found in dense irregular CT?

function of loose ct

Where is loose CT found in the body?

function of dense irregular CT

Where is dense irregular CT found in the body?

function of dense regular CT

Where is dense regular CT found in the body?

What type of adipose tissue?

What type of adipose tissue?

What type of adipose tissue?

What type of cartilage?

What type of cartilage?

What type of cartilage?

how was this bone prepared?

how was this bone prepared?

•“Fat” \n •Distributed throughout body, both in specific deposits and embedded within other tissues

functions of adipose tissue

name of adipose tissue cells

Adipocytes are dominated by internal ______ deposits

does adipose tissue have a lot of ecm?

is adipose tissue highly vascularized

2 types of adipose tissue

function of brown adipose tissue

functions of white adipose tissue

in white adipose tissue, cytoplasm is dominated by ______

Fatty acid storage and release is regulated by ________

–____ from ____ stimulates uptake/storage \n –_____ from pancreas and _____ from ________ stimulate release

White adipose tissue secretes hormones called _____ that help to regulate body weight and energy homeostasis

best studied adipokine known to act on hypothalamus and regulate satiety and energy expenditure

White adipose tissue also releases signals called ______ that stimulate the immune system

brown adipose tissue structure consists of…

brown adipose tissue has abundant ____ resulting in ______ cytoplasm

\n process that generates heat in response to norepinephrine from sympathetic nervous system

thermogenesis triggers hydrolysis of triglycerides and activation of _______ in mitochondria

BAT mitochondrial enzymes generate ___ during atp production

in who is BAT more abundant

Individuals with higher proportions of BAT have _____ \n metabolic rates

what is cartilage made of?

Chondrocytes produce and secrete abundant ECM, then become trapped in that ECM in cavities called _______

cartilage ECM is _____ and lacks ______

Cartilage ECM has lots of ground substance that forms a gel that is good at absorbing shock

Some types of cartilage are surrounded by a fibrous sheath called the ________ that holds vasculature

-smooth, faintly staining appearance in H&E staining

-ECM is strong and supportive, but more flexible than bone \n •EMC also has a gelatinous texture that makes it good for \n absorbing shock, and also good at reducing friction surfaces

where can hyaline cartilage be found?

-chondrocytes are located in lacunae, and separated from one another by extensive ECM

-in that it contains more fibers than hyaline– specifically, more elastic fibers \n •“streakier” in H&E; elastic fibers are even more prominent \n when using specialized stains such as Verhoeff’s

which cartilage types can have perichondrium?

where is elastic cartilage found

-mixture of cartilage and dense CT

-ECM is enriched with collagen fibers, often in parallel arrays

-identifiable by the presence of collagen rich ECM, \n chondrocytes AND fibroblasts, and distinctive rows of chondrocyte isogenous groups packed in between collagen fibers

where is fibrocartilage found?

Types of cartilage w/ no perichondrium _____ capable of regeneration

Cancers within cartilage are ______ because cells are not effective at growth or division

Provides structure and support, Protection for vital organs, site of hematophatosis

bone cells within lacunae

what is bone ecm called?

Cells called _______ secrete type 1 collagen and ground substance in bone

Fibrous sheaths lining external surfaces of bone matrix

Fibrous sheaths lining internal surfaces of bone matrix

• Cells that can produce new bone matrix

• Tend to have basophilic cytoplasm

  • Lots of rough ER for collagen synthesis

• Can break down existing bone matrix

• Large, multinucletate cells

• Often slightly acidophillic cytoplsm

• place in solution to dissolve minerals, soften tissue, and re-expose original collagen foundation of bone ecm

  • Then stain/section

  • Keeps living cells alive

• grind down bone, typically unstained or treated w/ black ink that settles into cracks

  • No living cells

humerus, femur, etc

\n scapula, bones of the skull, ect

bones can contain what 2 regions?

layered bone

Within each layer of bone collagen fibers are organized in parallel bundles

-Bundles ________ to increase strength

\n In compact bone, cylindrical structures called ______ are apparent

Within osteons, lamellae are organized into _____ surrounding a central open space called the ________ holding blood vessels and nerves

Blood vessels also found in perforating canals which are called…

Osteocytes access volkmann canals via cytoplasmic projections which they extend through tiny tunnels in the matrix called ______

name each zone in an epiphyseal growth plate

If your diet is low in calcium, you may experience a decrease in bone density – why? Which cell type will be activated in response to low blood calcium concentration?

when does most bone development occur?

2 mechanisms to produce new bone