Connective Tissue Flashcards
What is epithelial tissue?
Sheets of tightly bound cells, found covering exposed areas and lining internal cavities. Provide selective absorption and protect.
What are the four primary tissue types in the body?
- Epithelial tissue
- Connective tissue
- Muscular tissue
- Neural tissue
Where can epithelial tissue be found?
Skin, digestive tract, kidneys,
What is leaky gut syndrome?
A condition where the normally tightly packed epithelial tissue is not as tightly packed. There are some gaps in the intestinal wall which allows matter and nutrients to seep out of the digestive tract, causing abdominal inflammation and bloating.
What does connective tissue provide?
Support and structure.
What does muscular tissue have the ability to do?
Contract and produce movement.
What does neural tissue do?
Conducts electrical impulses.
What are the three main categories of connective tissue?
- Connective Tissue Proper
- Fluid Connective Tissue
- Supporting Connective Tissue
What is the general composition of most connective tissue types?
Cells- adipocytes, mast cells, lymphocytes, fibroblasts (most common type- secrete collagen)
These cells make up the elements of the Extracellular matrix (ECM), which is the ground substance and fibers in the connective tissue
What is the most common type of cell found in connective tissue and what is its function?
Fibroblasts are the most common type of cell, they secrete collagen. This collagen makes up the ECM.
What are adipocytes and where are they found?
Adipocytes are specialized cells that store fat. They are found in connective tissue and play a crucial role in energy storage, insulation, and cushioning.
What are mast cells and where are they found?
Mast cells are immune cells that play a vital role in allergic reactions and inflammation. They release histamine and other inflammatory mediators, which cause blood vessels to dilate and become leaky. This allows immune cells to reach the injury or site of infection. Mast cells are also involved in wound healing and tissue repair, and are found in the connective tissue.
What are lymphocytes and where are they found?
Lymphocytes are a type of white blood cell that recognizes and destroys foreign invaders such as bacteria, viruses, and parasites. Lymphocytes are found in various tissues throughout the body, including connective tissue. There are two main types of lymphocytes- B cells and T cells. B cells produce antibodies to fight off infections, while T cells directly attack infected cells.
What are the four most common and important cells found in connective tissue?
- Adipocytes- Store fat
- Lymphocytes- Type of WBC that illicit immune response
- Fibroblasts- Secrete collagen that makes up ECM
- Mast cells- Allergic reactions and inflammation, release histamine that dilates blood vessels and allows blood to travel to area of injury
What are the two types of connective tissue proper?
Loose and dense
What is loose connective tissue proper and what kinds of tissue does it make up?
Fibers create a loose, open framework. Comprises areolar tissue, adipose tissue, and reticular tissue.
What is dense connective tissue and what kinds of tissue does it make up?
Fibers are densely packed. Comprises dense regular, dense irregular, and elastic tissue.
What are the two types of fluid connective tissue?
Blood and lymph.
Where is fluid connective tissue (blood) contained?
Blood is contained in the cardiovascular system.
Where is fluid connective tissue (lymph) contained?
Lymph is contained in the lymphatic system.
What are the two types of supporting connective tissue?
Cartilage and bone.
What is cartilage and what types make up the supporting connective tissue?
Solid, rubbery matrix. Hyaline cartilage, elastic cartilage, fibrous cartilage make up the supporting connective tissue.
What is supporting connective tissue (bone)?
Solid, with a crystalline matrix.
What are the three loose fibers that make up loose connective tissues?
Areolar tissue, adipose tissue, reticular tissue.
Areolar tissue
- Loose connective tissue
Found underneath epithelial surfaces (the outer layer of skin and organs), within most organs, and in mucous membranes. Provides support, flexibility, and wound healing to surrounding tissues.
Adipose tissue
- Loose connective tissue
Found underneath the skin, in the mesentery (a tissue that connects the intestines to the abdominal wall), and in bone marrow. Stores energy in the form of fat, provides insulation, and cushions organs.
Reticular tissue
- Loose connective tissue
Found in lymphoid organs, such as the spleen, bone marrow, and liver. Provides support for cells and fibers. Filters blood and produces WBCs.
Components of Areolar Tissue
- Loose connective tissue
- Fibrocytes- produce collagen and elastic fibers.
- Macrophage- large WBCs that play a crucial role in the immune system. Engulf and destroy foreign invaders, such as bacteria and viruses.
- Collagen Fibers- strong and flexible fibers that provide structural support to the tissue.
- Mast cells- specialized cells that release histamine, which is involved in allergic reactions and wound healing.
- Elastic Fibers- allow the tissue to stretch and recoil.
Characteristics of Adipose Tissue
Characteristic “soap bubble” appearance.
Adipocytes (white adipose cells) are fat reserves.
Infants and young children will also have brown adipose tissue. This brown adipose has a strong blood supply. Since their bodies are smaller, this brown adipose assists with heat generation to allow for thermoregulation.
Characteristics of Reticular Tissue
- A net-like appearance
- Rete= net or network
What are the three types of dense connective tissues in connective tissue proper?
Dense regular connective tissue, dense irregular connective tissue, elastic connective tissue
Dense Regular Connective Tissue
Tendons, ligaments, aponeuroses (collagen fibers and fibrocyte nuclei)
Dense Irregular Connective Tissue
Skin dermis, capsules of organs (collagen fiber bundles)
Elastic Connective Tissue
In walls of large arteries, ligaments in spine, lungs, bladder (elastic fibers and fibrocyte nuclei)
What are the two types of fluid connective tissues?
Blood- located in the cardiovascular system
Lymph- located in the lymphatic system
What is the purpose of supporting connective tissue and what are the two kinds of supporting connective tissue?
Supporting connective tissue provides a strong framework that supports the rest of the body. Comprised of cartilage and bone.
What is cartilage made of?
Chondrocytes
What is bone made of?
Osteocytes
What are the three types of cartilage?
Hyaline, elastic, fibrous
Where is hyaline cartilage found?
Articular surfaces of bones, most major joints
Where is elastic cartilage found?
External ear
Where is fibrous cartilage found?
Intervertebral disks
Important points about cartilage
- Cartilage has a gelatinous matrix
- Cartilage is avascular (nourished by diffusion from nearby tissues)
- Because it is avascular it does not heal effectively
- Note the cartilage worn away in this example of the knee joint
What are the two types of bone?
Compact and spongy
Bone has a solid matrix. This matrix is dominated by calcium deposits which gives bone its hardness. Blood vessels travel within the central canals of the compact bone.
What is the purpose of the connective tissue framework of the body?
Connective tissue creates the internal framework of the body. Layers of connective tissue, called fascia, connect organs with the rest of the body.
What are the layers of connective tissue?
Superficial fascia (subcutaneous layer)
Deep fascia
Subserous fascia
Superficial Fascia
- Between skin and underlying organs
- Areolar tissue and adipose tissue
- Also known as subcutaneous layer or hypodermic
Deep Fascia
- Forms a strong, fibrous internal framework
- Dense irregular connective tissue
- Bound to capsules, tendons, ligaments, etc
Subserous Fascia
- Between serous membranes and deep fascia
- Areolar tissue
Myofascia
Deep Fascia
- Fascia covering skeletal muscles
Myofascial Pain Syndrome
Chronic pain disorder. Pressure on sensitive points in muscle triggers pain in unrelated body parts. Referred pain.
Tissues and Aging
Repair and maintenance become less efficient as one ages- less collagen is made and it breaks down more quickly. Hormonal changes and lifestyle changes also affect the functioning of tissues. Connective tissues become fragile. A reduction in bone strength, osteoporosis.
Sarcoma
Cancer of the connective tissue
Fibrosis
Scarring and thickening of connective tissue, excessive collagen can be laid down, organ function can be severely affected
Scleroderma
Thickening, tightening, rigidity of facial skin, extensive dermal collagen deposition with some epidermal atrophy, and sclerodactyly, which causes the fingers to be partially fixed in a semi flexed position
Ehlers Danlos Syndrome
Loose skin, hyper mobility at joints due to lack of collagen
Anaphylaxis
Allergic reaction (cells part of the connective tissue system secrete biochemicals that lead to redness/swelling
Fasciotomy
Cutting through a layer surrounding muscle in order to relieve pressure being placed on that compartment, usually occurs in the legs
Marfan Syndrome
Excessively long limbs, structural issues in the heart and major blood vessels, especially the aorta
Osteogenesis Imperfecta
A genetic bone disease where collagen is not formed or malformed, bones are brittle and prone to breakage. The sclera takes on a blue/gray color because of the lack of collagen. The underlying vasculature gives this appearance.
