Module 4: Unit 1-3 Flashcards
T or F
Adipose is a type of fibrous tissue
False,
Adipose is a type of CT, and made of adipocytes
Where does adipose originate from?
Embryonic mesenchyme
T or F
Adipose is a poor conductor of heat
T
T or F
Adipose tissue is found in connective tissue proper as individual cells or small cell groups
True
T or F
Adipose tissue is highly vascularized and innervated
True
Name the general functions of adipose tissue.
- Store fat (triglycerides)
- Produce hormones: ex-Lipton hormone
- Thermal insulation of the body
- Acts as a filler tissue-keeps organs in place
- Found more on surfaces that experience more abrasion for cushion
What are the two types of adipose tissue?
White adipose tissue
Brown adipose tissue
Explain white (unilocular) adipose tissue.
- Cells have 1 big lipid droplet
- Cytoplasm pushed along the periophery
- Found on the body, in hypodermic as insulation, surrounds many organs
Explain brown (multilocular) adipose tissue
- Cells have many lipid droplets
- Central cycle us, high number of Mitochondria
- Found more in babies, very little in adults
*MAKE CARD OF CHARACTERISTICS/UNILOCULAR FAT/MULTILOCULAR on adipose slides
Look at cartilage locations, slide #3
What percentage of your body weight does adipose make up?
15-20% of normal body weight
T or F
Adipocytes store neutral fats, orginiate from embryonic mesenchyme as lipoblasts that gradually accumulate fat (triglycerides droplets) in their cytoplasm, and blocks the production of hormones like Leptin that regulates appetite.
False,
Adipocytes produce hormone like Leptin that regulates apppetitie
Adipose acts as a cushion for?
A. Head
B. Eyes and tongue
C. Palms, heels, toes
D. Elbow and knee
C
T or F
Adipocytes regulate body’s metabolism
T
Name locations of adipose insulation
In hypodermic/subutis, in abdomen, buttocks, axilla & thighs
Does adipose provide cushion around organs? How?
Retro peritoneal space (around kidney), visceral pericardium, around the eye-ball
Explain the hormone secreting process of adipose tissue.
Leptin! Regulator of energy homeostasis —> inhibits food intake (Leptin is a circulating satiety factor) & loss of body weight, and stimulates metabolic rate. Leptin deficiency causes obesity. Other hormones: angiotensinogen, adiponectin (regulates fatty acid breakdown), resistin etc.
T or F
Adipose is the only tissue that does not originate from the embryonic mesenchyme
F
T or F
White adipose produces Leptin hormone
T
T or F
Brown adipose tissue is totally absent in adults
F
T or f
White adipose found int he hypodermic acts as an insulating layer for the body
T
T or F
Adipose cells are surreounded by large number of BV, but is not highly vascularized
F
Adipose cells are surrounded by large number of BV, and this tissue is highly vascularized
T or F
Adipocytes increase in number during the first 10 years of life, after that is slows or stops.
T
T or F
Weight gain later in life is primarily due to the decrease in adipocytes by the decrease in lipid droplets in their cytosplasm
F
Weight gain later in life is primarily due tot he increase in size of the adipocytes by acquiring more lipid droplets in their cytoplasm. Hence the proliferation (increase in number) of adipocytes in early life can be a major determinant of the tendency for weight gain later in an individual’s life
Differentiate Brown adipose cells from White adipose cells.
BAC have nucleus centrally located and not squeezed towards the periphery - they are present around the BV
WA is found under the skin in the hypodermic - as a thermal insulator, on the belly, buttocks etc as a cushion
T or F
The distribution of WA is dependent on the hormones- changes after childhood going into puberty generally deposited in the breast and thighs
T
Where is white (unilocular) adipose tissue found?
Found on the belly, in hypodermic as insulation, surrounds many organs.
FITB
In a growing white adipocytes large numbers of _______ are seen, and these ______ are invaginations/depressions in the cell membrane.
Caveolae
FITB
____________ play an important role in lipid trafficking because a growing adipocytes will be constantly collecting lipid drops from its surroundings and adding it to its cytoplasmic lipid drop and as it grows in size
Caveolae
What does the color of adipocytes in freshly dissected sections depend on?
The amount of carotenoids dissolved in it
Which adipose produces heat? How
Brown adipose,
In the BA mitochondrion, due to thermogenesis the protons enter the mito, matrix without having to pass through the ATP synthesise. This causes the released energy to dissipate in the form of heat and not become ATP. Thus producing heat and this process is called non-shivering thermogenesis.
Why is there a large amount of BA in newborns?
To prevent the extensive heat loss (major risk of death in premature baby) infants cannot voluntarily cause their skeletal muscle cells to contract and make heat
Where are minimum amounts of brown fat found int he an adult?
Region around kidney
Adrenal glands
Around large vessels
Region of neck, back, - mostly in males
Mediastrinum
Near esophagus and trachea
Be able to explain the process of thermogenin
Brown adipose producing heat. Thermogenin allows for the production of heat in BA
of lipid droplets in unilocular fat vs multilocular fat
1 in uni
Many in multi
T or F
Unilocular fat and multilocular fat are persistent in adulthood
T
Function of unilocular fat
Hormone production, cushion, and insulation
Multilocular fat function
Production of heat
T or F
Both unilocular fat and multilocular fat come from embryonic mesenchyme
What are the three types of cartilage?
Hyaline, elastic, and fibrocartilage
State the composition of cartilage.
Avascular tissue (nutrition enters by diffusion from surrounding BV)
Cells: chondroblasts and chondrocytes inside lacuna
Intercellular matrix: dense but soft, rich in proteoglycans, collagen type 2
Most common type of cartilage is?
Hyaline
What does the cartilage in the trachea do?
Allow for the respiratory branches to stay open and not collapse.
Where can fibrocartilage be found?
Pubic symphysis, intervertebral disks, articular cartilage of a joint (within the knee = meniscus)
Where can elastic cartilage be found?
Cartilage in external ear, and epiglottis
Auricle of the ear, External auditory canal, epiglottis
Where can hyaline cartilage be found
Costal cartilage, articular cartilage of a joint, cartilages in nose, etc.
T or F
Cartilage is avascular tissue
True,
Nutrition enters by diffusion from surrounding BV
What is the Lacuna?
Space left outside a cell within the matrix after the cells stop secreting the matrix anymore and undergo atrophy (cell shrinking)- chondrocytes are comparatively less active cells - but alive - found deeper in the cartilage tissue. The active cells that are secreting matrix are called chondroblasts, they are found in the periphery of the cartilage tissue
FITB
____________ is the most common type of collagen found in cartilage
Collagen type 2
How does nutrients diffuse through the matrix ?
Diffuses through the matrix via the highly sulfation ground substance - high sulfation means increased binding to water- which allows the cartilage to act as a shock absorber…
What happens to mature cells when they become less active?
They shrink,
Because the matrix of both cartilage (and bone) is more or less rigid, it does not “shrink” with the cells, so, a small space remains around the cells called a lacuna.
What are isogenous cells?
Cells coming from the same mother cell
cell groups are also called “NEST” cells
What is perichondrium?
Connective tissue covering, that is found surrounding all types of elastic cartilage
T or F
All types of cartilage lack vascular supply
T,
Thus the chondrocytes receive nutrients by diffusion from capillaries that are found in the surrounding dense connective tissue (the perichondrium). For this reason, cartilage tends not to be Avery thick tissue. Further, the diffusion process requires motion to function properly..
What are young chondrocytes called?
Chondroblasts
Perichondrium surrounds almost all cartilages. EXCEPT?
Joint cartilage (has no perichondrium) - sustained but eh diffusion of oxygen and nutrients from the synovial fluid
Perichondrium has fibers made of?
A. Collagen type 3 fibers
B. Collagen type 1 fibers
C. Collagen type 2 fibers
D. Collagen type 4 fibers
B
T or F
Perichondrium its important for the growth (appositional growth) and maintenance of cartilage
T
When 1 cell can give rise to a group of up to eight cells by mitosis.
Called isogenous groups or nest cells
T or F
The matrix is high in PGs and low in collagen type 3
F
The matrix is high in PGs and low in collagen TYPE 2
The matrix that is farther away from individual cells and is found in the space between the groups (lightly stained) is called the inter territorial matrix. The interterritorial matrix is high in collagen type 2; thus, PGs are proportionately low
Explain why we find more collagen type 2 fibers in the interterritorial matrix compared to the territorial matrix.
Collagen is a protein that is first secreted as tropocollagen. It undergoes fibrillogensis outside the cell. So, when the tropocollagen is first secreted, it is obviously going to be found in the immediate surrounding of the cells. As the cell secretes more and more matrix material, this tropocollagen is gradually pushed away from the cells and has had the chance to undergo fibrillogenesis. Thus you find more CT2 fibers in the interterritorial matrix compared to the territorial matrix.
Explain the process of Lacuna formation.
—>The perichondrium supples fresh chondroblasts
—> These chondroblasts are actively secreting matrix
—> As they are secreting more and more matrix, the cells are inevitably moving father away from each other
—> At the same time, these chondroblasts also undergo cell division and thus produce isogenous groups of cells. Now, all these cells will gradually be embedded in the cartilage tissue as they make more matrix around them.
—>the cells that reach this point will slow down in function and stop cell division
—> Now, they are called chondrocytes. As they slow their function, they SHRINK. Due to shrinkage, the cells leave a space around them called the LACUNA
What are highly sulfated, bind to water, makes cartilage flexible and shock absorbing?
GAGs
Approximately 75% of the wet weight of hyaline cartilage is _________
Water
Matrix is made up of ________
Collagen type 2 fibers
What is the territorial matrix vs the interterritorial matrix?
Come back
Hyaline cartilage is found where?
- Articular surfaces of diarthroses
- Epiphyseal plate
- wall of trachea and bronchi
- ventral end of ribs
- endochondral ossification
- cartilage of the larynx
What does hyaline cartilage receive its nutrients from?
The perichondrium or the synovial fluid (in articular cartilage)
T or F
Collagen Type II is found in the matrix
True
T or F
Elastic cartilage contains type II collagen, hyaline cartilage and elastic fibers
F
Just type II collagen and elastic fibers
What cartilage lacks perichondrium?
Fibrocartilage
In what cartilage is majority of type 2 collagen in the matrix. Where Type 1 collagen can be found, and acts as a supporting tissue.
Fibrocartilage
T or F
Fibrocartilage has more Type 1 collagen fibers than T2
F
Has more Type 2 than Type 1
Name the cartilage
Mechanical shock absorber
Hyaline and fibrocartilage
Name the cartilage
Provide smooth-surfaces —> lining surfaces of joints
Hyaline and fibrocartilage
Name the cartilage
Structural support for respiratory tract and bronchial tree
Hyaline cartilage
Name the cartilage
Gives shape and support to soft tissues- external ear pinna
Elastic cartilage
Name the cartilage
Provide suctioning and tensile strength
Fibrocartilage and hyaline
Name the cartilage
May act as a model for bone formation (endochondral ossification)
Hyaline cartilage
T or F
Cartilage is highly vascular in nature
F
T or F
Coastal cartilage is a type of elastic cartilage
F
T or F
CT1 is the most common type of collagen in cartilage
F
T or F
Endochondral ossification involves a stage of hyaline cartilage scaffold
T
T or F
Fibrocartilage also contains CT1 in its matrix
T
T or F
Hyaline cartilage forms the fetal skeletal scaffold during development
T
T or F
Interterritorial matrix is high in tropocollagen molecules
F
T or F
Perichondrium cases appositional growth of the cartilage
T
T or F
Perichondrium is only found around hyaline (except articular) and elastic cartilage
T
What are the four main bone functions? Describe them
Structural - provide structural support to the body; attachment for muscles
Protection - protect organs
Storage - main depot of calcium and phosphorus
Sanctuary - postnatal hematopoiesis (hosts the red bone marrow)
Bone is a connective tissue consisting of ____________, ____________, ______________
And a non-living component called _________-___________
Osteoblast, osteocyte, osteoclast
Bone-matrix
What do osteoblasts do?
Bone building cells, that secrete the matrix forming bone. Highly active
Alkaline phosphotase
Osteocyte
Less active than osteoblasts
What is an osteoclast?
Interacting with bone tissue and assists in breaking down of bone to rebuild. Takes away minerals. Will assist in cleaning powdered bone.
Acid phosphatase
Bone cells: Osteoblasts
Found where?
Mononuclear cells found on the surface of bone trabeculae
The hard extracellular matrix has a term referred to as?
Osteoid
T or F
Osteocytes are a mature form of osteoblast
T
T or F
Osteoclasts are motile and mononucleated
False,
They are motile and MULTInucleated
Bone cells: Osteoclasts
Cytoplasm contains abundant vesicles/vacuoles and lysosomes. When active, they break down bone tissue leaving a depression called the ________ _________
Howship’s lacuna
What is Howship’s lacuna?
Small depressions on cancellous bone surface, occupied by the osteoclast.
This depression is due to an erosion by the osteoclast enzymes
Bone matrix consists of: (2 components)
*Organic components
- Type I collagen (90%)
- Proteoglycans
- Glycoproteins: ostenectin, osteocalcin
*Inorganic components (50% of bone dry weight):
- calcium hydroxyapatite
- Bicarbonate, citrate, magnesium, potassium, sodium, calcium and phosphate also found
- Water
Name the two types of bone.
Cancellous (spongy/trabecular) bone
Compact bone
Cancellous (spongy) bone is made up of ____________ and ___________
Trabeculae and spicules
What system is associated with structure of compact bone?
Structure is made of Osteon (Haversian) systems
What type of connective tissue is periosteum and endosteum?
Dense irregular connective tissue
Periosteum is connected to the bone with the help of _________ fibers.
Sharpey’s
These fibers act like a compression bandage over the bone. Periosteum is a type of dense irregular CT
FITB
______________ is on the inner side of the- a reservoir of stem cells - when you break a bone - this will supply new cells like the osteoblasts to help remake the bone.
Endosteum
The cells in here are more squamous like cells with multi potential. It lines the marrow cavity as well as the big canals. (Haversian canal and volkmann’s canal.
An outer later of collagen fibers and fibroblasts, deeper inside the periosteum layer, you find osteoprogenitor cells that easily differentiate into osteoblasts.
Periosteum
Found lining the marrow cavity it has only a single layer of osteoprogenitor ells and CT
Endosteum
Describe the four bone fracture repair steps.
1 - a fracture hepatoma forms
2 - a fibrocartilaginous (soft) callus forms
3 - a hard (bony) callus forms
4 - The bone is remodeled
Name aspects of osteoblasts specific to that cell.
Alkaline phosphates activity
Mononucleated
Mesenchyme origin
<—Surface of cell —>
Name aspects of osteoclasts specific to that cell.
Acid phosphatase activity
Cathepsin K
Multinucleated
Howships Lacuna
Mobile, originate in bone matrix
<— surface of cell—>
Name aspects of cancellous bone vs compact bone/cortical.
Cancellous bone - spicule —> Trabecula
Function = houses the bone marrow
Compact bone - Osteon
Function = structural, reservoir
Found in the cortex
T or F
All bone cells are multinucleated
F
T or F
Bone fracture healing involves the formation of fibrocartilage and not hyaline cartilage
T
T or F
Calcium hydroxyapatite is the primary bone mineral
T
T or F
Canaliculi help transport nutrients from one concentric lamella to another
T
T or F
Haversian canals contain both, BV and nerves
T
T or F
Interstitial lamellae are older concentric lamellae after bone remodeling
T
T or F
Osteoclasts originate from monocytes
T
T or F
Osteocytes reside in howship’s lacuna until they die
F
T or F
Periosteum and endosteum both supply osteoprogenitor cells
T
T or F
Sharpey’s fibers are found under the endosteum and line the marrow cavity
F
T or F
Since compact bone is dense, it is easier to realise mineral from it when the body needs
F
T or F
The bone marrow is found in the spaces of cancellous bone
T
T or F
The smallest structural unit of the spongy bone is Trabecula
F
What hormone acts to get Ca out of the bone into the blood by increasing Osteoclast activity?
Parathyroid hormone(secreted by the parathyroid gland)
