Module 4 Unit 2-4 Flashcards
What percentage of adipose makes up normal body weight?
15-20%
What does adipocytes store? Where do they originate from? What hormone do they produce?
Stores neutral fats
Originate from the embryonic mesenchyme as lipoblasts
Produces leptin hormone that regulates appetite
What does adipocytes in the body regulate?
Body’s metabolism
What parts of the body does the adipocytes act as cushion?
Palms, heels, toes, etc.
What are the general characteristics of adipose? Name 6 of the 11 characteristics
- A type of CT
- Made of adipocytes
- Originates from embryonic mesenchyme
- Poor conductor of heat
- Found in connective tissue proper as individual cells or small cell groups
- Highly vascularized and innervated
- Store fat (triglycerides)
- Produce hormones: Leptin 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 form is the energy molecules in the adipose called?
Form of triglycerides droplets
Where is the adipose tissue used as cushion in the vital organs?
Retroperitoneal space (around kidney), Visceral pericardium, around the eye-ball
What does the hormone Leptin do?
Leptin regulator of energy (homeostasis); inhibits food intake, loss of body weight, and stimulates metabolic rates
How many lipids droplets in the the cytoplasm in white adipose tissue?
1 large droplet of lipid
How many lipids droplets in the the cytoplasm in brown adipose tissue?
Numerous small lipid droplets
Why is the nucleus in the cytoplasm on the periphery of the cell in the white adipose tissue?
The lipid droplet is so large.
Where is the white adipose tissue found? What is the significance of this location?
Under the skin in the hypodermis
Specific as a thermal insulator - belly, buttocks, etc. as a cushion
Where is the brown adipose tissue found?
Present around blood vessels
Where is the nucleus in brown adipose tissue? What other organelle does it also have?
Central nucleus
High number of mitochondria
Who has more brown adipose tissue babies or adults? Why?
Babies because they cannot voluntarily cause their skeletal muscle cells to contract to make heat. Brown adipose tissue helps them maintain body heat.
Where is brown adipose tissue located in adults? (Hint: there are 6 places)
- Region around the kidneys
- Adrenal glands
- Around large vessels (eg. aorta)
- Regions of neck, back (interscapular) - mostly in males (near C1, C2)
- Mediastinum
- Near esophagus and trachea
What are the different functions of unilocular fat and multilocular fat?
Unilocular fats (white adipose) - hormone production, insulation, and cushion
Multilocular fats (brown adipose) - production of heat
Where is elastic cartilage found?
External ear
Epiglottis
Auditory canal
Where is the fibrocartilage located?
Intervertebral discs
Meniscus
Symphyses
Where is the hyaline cartilage located?
Articular cartilage
Costal cartilage
Nose
Larynx
Epiphyseal plates
Temporary: template of long and irregular bones
Since cartilage is avascular, how does it get its nutrients?
Diffuse through the matrix via the highly sulfated ground substance
sulfation means increased binding to water
What is a lacuna?
Space left outside a cell within the matrix after the cells stop secreting the matrix anymore and undergo atrophy (cell shrinking)
Where are the chondrocytes found in the cartilage? How active are they?
Found deeper in the cartilage tissue
less active cells, but is still alive
Where are the chondroblasts found in the cell? How active are they?
Found in the periphery of the cartilage tissue
Is very active
What happens to mature cells as they become less active? Why does this happen?
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 surrounds almost all cartilage except joint cartilage?
Perichondrium
How is the perichondrium sustained?
By the diffusion from capillaries that are found in the surrounding dense connective tissue
How is the joint cartilage sustained?
The diffusion of oxygen and nutrients from the synovial fluid
What type of collagen is perichondrium made of?
Collagen Type 1
Why is the perichondrium important?
For the growth and maintenance of cartilage
What is it called when 1 cell can give rise to a group of up to eight cells by mitosis?
Isogenous groups or nest cells
What is the darker color matrix surrounds the isogenous group of chrondrocytes called?
Territorial matrix
Does the territorial matrix have high or low proteoglycans? Does the territorial matrix have high or low collagen type 2?
High in proteoglycans and low in collagen type 2
Does the interterritorial matrix have high or low proteoglycans? Does the interterritorial matrix have high or low collagen type 2?
Low in proteoglycans and high in collagen type 2
What is the percentage of water weight is the hyaline cartilage?
75%