Question

complete the following statements to explain the purpose of the extracellular matrix.

1. a(n) click to select is a meshwork of fibrous proteins and polysaccharides.
2. two well-known proteins are click to select, which resists stretching, and click to select, which gives the resilience.
3. the role of click to select is to direct the migration of cells during development.
4. a tissues extracellular matrix (ecm) can vary greatly, from flexible cartilage to rigid bone, depending on the types and arrangement of click to select present.

Explanation:

Define the extracellular matrix

The extracellular matrix (ECM) is an intricate, non-cellular network of macromolecules that provides structural and biochemical support to surrounding cells. It is primarily composed of a meshwork of fibrous proteins (such as collagen and elastin) and polysaccharides (such as glycosaminoglycans and proteoglycans). Therefore, the first blank is "extracellular matrix".

Identify structural proteins of the ECM

Two of the most abundant and well-characterized fibrous proteins in the extracellular matrix are collagen and elastin:

• Collagen forms incredibly strong fibers that resist stretching and pulling forces, providing tensile strength to tissues.
• Elastin is a highly elastic protein that allows tissues to stretch and then recoil back to their original shape, providing resilience and elasticity.

Thus, the second blank is "collagen" and the third blank is "elastin".

Determine the role of fibronectin

Fibronectin is an adhesive glycoprotein in the extracellular matrix that binds to both integrins (receptor proteins spanning the cell's plasma membrane) and other ECM components like collagen. By bridging the cell and the matrix, fibronectin plays a crucial role in cell adhesion, growth, and directing the migration of cells during embryonic development. Thus, the fourth blank is "fibronectin".

Analyze ECM variation across tissues

The physical properties of a tissue's extracellular matrix vary dramatically depending on its specific physiological role. For example, cartilage is flexible and shock-absorbing, whereas bone is highly rigid and mineralized. This variation is determined by the specific types, quantities, and structural arrangement of the proteins and polysaccharides (or fibers and ground substance) present in the matrix. Thus, the final blank is "proteins and polysaccharides".

Answer:

Question 1

1. A(n) <blank>extracellular matrix</blank> is a meshwork of fibrous proteins and polysaccharides.

Question 2

1. Two well-known proteins are <blank>collagen</blank>, which resists stretching, and <blank>elastin</blank>, which gives the resilience.

Question 3

1. The role of <blank>fibronectin</blank> is to direct the migration of cells during development.

Question 4

1. A tissue's extracellular matrix (ECM) can vary greatly, from flexible cartilage to rigid bone, depending on the types and arrangement of <blank>proteins and polysaccharides</blank> present.