Ch 3 Clinical Case Activity

The odd position of Jackson's heart is related to a disorder with his cilia called Primary Ciliary Dyskinesia (PCD). What are cilia? Cilia are numerous motile extensions of the plasma membrane that have an internal arrangement of nine pairs of microtubules surrounding a central microtubule pair (9+2 array). Cilia are finger-shaped cytoplasmic projections of the plasma membrane that increase the surface area of the cell. Cilia are very long singular extensions of the cytoplasm. They have an internal arrangement of nine pairs of microtubules surrounding a central microtubule pair (9+2 array). Cilia exist in pairs and are structures composed of an internal arrangement of nine microtubule triplets arranged in a cylindrical structure.

Cilia are numerous motile extensions of the plasma membrane that have an internal arrangement of nine pairs of microtubules surrounding a central microtubule pair (9+2 array). The internal "9+2" array of microtubules is anchored to the basal body, a structure located beneath the cell membrane that is also composed of microtubules.

Cilia are composed of microtubules. How are microtubules different from the other cytoskeletal filaments? Microtubules are large bundles composed of the protein myosin. They are generally 15 nanometers in size. Microtubules are the smallest cytoskeletal element with a diameter of 5 nanometers and they are composed of the protein actin. Microtubules vary in size from 9-11 nanometers and have different protein compositions depending upon the type of cell. Microtubules are hollow tubes with a diameter of 25 nanometers and are composed of the protein tubulin.

Microtubules are hollow tubes with a diameter of 25 nanometers and are composed of the protein tubulin. Microtubules are hollow and are the largest of the cytoskeletal filaments.

The majority of individuals with PCD have defects associated with the ciliary protein dynein, which functions in the cilia's motility. Many of these affected individuals have mutations associated with two genes: DNAI1 and DNAH5. How do genes relate to proteins? a. Genes are a set of nucleotides in a strand of DNA that specify the specific sequence of the amino acids that comprise a protein. b. Genes are a type of RNA molecule that brings the appropriate amino acids to the ribosome complex during protein synthesis. c. Genes are the molecules of RNA that translocate from the nucleus to associate with ribosomes during translation of protein synthesis. d. Genes are the molecule that adds the nucleotides to the RNA strand during transcription. Mutations in these molecules cause the wrong nucleotides to be inserted, ultimately creating a fault protein during translation.

a. Genes are a set of nucleotides in a strand of DNA that specify the specific sequence of the amino acids that comprise a protein. Mutations are permanent changes to the sequence of nucleotides in DNA and can result in alterations to the structure and function of a protein.

Jackson has a PCD (primary cilia dyskinesia) where his cilia have defects that affect their motility. How is this related to Jackson's respiratory symptoms? a. Motile cilia are found on cells lining the airways and function to help push air in and out of the lungs. When an individual has PCD, their cilia is immotile and they have trouble breathing. b. Motile cilia function to trap and ensnare contaminants like bacteria, marking them for removal by phagocytic cells. When the cilia cannot move, the bacteria do not get trapped and removed and thus can cause respiratory infections. c. Motile cilia are found on the cells that line the trachea. The cilia produce mucus and then by moving together, distribute the mucus evenly over the cell's surface. When the cilia have motility issues, the mucus is not spread evenly and forms thick clumps that irritate the airways and cause a chronic cough and respiratory infections. d. Motile cilia are found on cells lining the trachea. The cilia move together in a coordinated wave, helping to push contaminated mucus and fluids out of the respiratory tract. When the cilia have motility issues, these secretions are not cleared and respiratory infections are the common result.

d. Motile cilia are found on cells lining the trachea. The cilia move together in a coordinated wave, helping to push contaminated mucus and fluids out of the respiratory tract. When the cilia have motility issues, these secretions are not cleared and respiratory infections are the common result. The ability of cilia to move is critical to their function.