Connective Tissues Flashcards
How do you classify connective tissues?
embryonic and mature
What type of connective tissue is mesenchyme? Give examples
embryonic: ectoderm, mesoderm, endoderm
What type of connective tissue is mucous connective tissue? Give example
embryonic: umbillical cord
What are the six types of mature connective tissue?
loose, dense, cartilage, bone, blood, lymph
When in life is mature connective tissue present? Where is it developed?
present after birth, developed from the mesenchyme
What are the three types of loose connective tissue?
areolar, adipose, reticular
Which type of loose connective tissue is the most widely distributed?
areolar
Adipocyte have one single ___________ droplet
triglyceride
What loose connective tissue is the stroma of organs, for example, liver, spleen, and lymph nodes?
reticular
What are the three types of dense connective tissue?
dense regular, dense irregular, elastic
What is dense regular tissue?
collagen arranged in bundles
What is dense irregular tissue?
collagen arranged irregularly
What is elastic dense connective tissue?
contains elastic fibres
Give 3 examples of dense regular tissue
forms tendons, ligaments, aponeuroses
Give 3 examples of dense irregular tissue
forms muscle fascia, fibrous pericardium, periosteum
Give 4 examples of elastic dense connective tissue
lung, artery, trachea, bronchial tubes
What is cartilage?
a dense network of collagen and elastic fibres embedded in chondroitin sulfate
What gives cartilage its strength?
collagen
What gives cartilage its resilience and allows it to re-assume its original shape after deformity?
chondroitin
What are cartilage cells called?
chondrocytes
Where do chondrocytes occur?
within spaces called lacunae in the matrix
What is the surface of most cartilage covered by? What does it contain? Are there exceptions?
perichondrium which contains BV and nerves. Exceptions: articular cartilage and growth plate cartilage
What are the functions of cartilage?
plays important role as supporting tissue and is the precursor of bone and growth plates within bones
True or false: cartilage is a relatively active tissue, grows quickly and repair proceeds quickly
False: cartilage is a relatively INACTIVE tissue, grows SLOWLY and repair proceeds SLOWLY
What are the two patterns of cartilage growth?
interstitial and oppositional
Describe interstitial cartilage growth
occurs during childhood and adolescence, the expansion occurs from within like bread rising
Describe oppositional cartilage growth
Starts later. Growth occurs at the outer surface. Cells of Perichondrium differentiate into Chondroblasts
Does cartilage have nerves and blood vessels?
Does not have nerves, does not have blood vessels
Why doesn’t cartilage have blood vessels?
Secretes a substance preventing blood vessel growth!
What are the three types of cartilage?
- Hyaline Cartilage
- Fibrocartilage
- Elastic Cartilage
What is the most abundant types of cartilage?
The Hyaline Cartilage
Where is hyaline cartilage located?
Located in: • Ends of long bones • Costal cartilage • Nose, larynx, trachea, bronchi • Embryonic and fetal skeleton
What is the weakest type of cartilage? Why?
The Hyaline Cartilage. Weakest type of cartilage. Has
no fibers in the matrix
In what type of cartilage are the chondrocytes located among bundles of collagen fibers?
The Fibrocartilage
What type of cartilage lacks perichondrium
The Fibrocartilage
Where is fibrocartilage present?
Present in:
• Pubic symphysis
• Intervertebral discs
• Menisci
What is the strongest type of cartilage?
The Fibrocartilage
In what type of cartilage are the chondrocytes placed in a threadlike network of elastic fibers?
The Elastic Cartilage
In elastic cartilage is the perichondrium present?
Yes
Where is elastic cartilage present?
Present in:
• Epiglottis
• External ear
What tissues are bones composed of?
- Osseous tissue
- Periosteum
- Red and Yellow Bone Marrow
- Endosteum
What are the 4 types of cells that osseous tissue contains?
- Osteoprogenitor cells (bone stem cells able to differentiate into the other
types of cells) - Osteoblasts (bone-building cells that secrete matrix)
- Osteocytes (mature bone cells)
- Osteoclasts (remodel bones and cause them to release calcium)
What do osteoprogenitor cells do?
Osteoprogenitor cells (bone stem cells able to differentiate into the other types of cells)
What do osteoblasts do?
Osteoblasts (bone-building cells that secrete matrix)
What are osteocytes?
Osteocytes (mature bone cells)
What do osteoclasts do?
Osteoclasts (remodel bones and cause them to release calcium)
How do you classify bones?
- Compact Bone
2. Spongy Bone
What is the basic unit of compact bone?
The basic unit is the osteon
What are lamellae?
Concentric rings of mineral
What are lacunae?
Spaces between lamellae that contain osteocytes
What are canaliculi?
Routes for nutrients and waste exchange for
osteocytes
What is a central canal?
Contain blood vessels
What is spongy bone also known as?
Cancellous Bone
Spongy bone consists of columns of bone called____________ that contains:_______,_________,_______
Consists of columns of bone called trabeculae, which contains:
• Lamellae
• Osteocytes in lacunae
• Canaliculi
What does compact bone have that spongy bone does not?
A Central Canal
How are the osteons aligned in compact bone? What is the result?
• Aligned parallel to the longitudinal axis
of the diaphysis
• Provides high resistance
How are osteons in spongy bone aligned?
Does not contain osteons. Consists
of trabeculae
What is the periosteum
Tough connective tissue sheath and
associated blood supply covering the
bone, except the articulating surfaces
What is the periosteum composed of?
Composed of two layers:
• Outer fibrous layer
• Dense irregular connective tissue
• Inner osteogenic layer
• Composed of cells that enable bone
thickness growth
How does the periosteum protect the bone?
Protects the bone attaching to it by perforating fibers (Sharpey’s fibers)
Other than protecting the bone, what are the functions of the periosteum?
• Assists in fracture repair
• Helps nourishing the bone
• Serves as an attachment point for
ligaments and tendons
What is the endosteum
• Lines the medullary cavity
• Single layer of bone-forming cells
• Contributes to the thickening of the
bone
Describe yellow bone marrow
• Fatty tissue occupying the marrow cavity within the diaphysis • Stores triglycerides as potential chemical energy reserve • Contributes minimizing the weight of long bones without compromising strength
Describe red bone marrow
• Connective tissue that generates the blood cells by hemopoiesis • Consists of developing blood cells, adipocytes, fibroblasts, and macrophages within a network of reticular fibers. • Only present in some bones in the adult: coxal, sternum, vertebral bodies, ribs, and skull
What bones is red bone marrow present?
Infants
• Only present in some bones in the
adult: coxal, sternum, vertebral bodies,
ribs, and skull
Does an infant skeleton (<1yr) contain only red or only yellow bone marrow?
Red
