Question

practice mini frq

1. hepatitis c is a virus that attacks the liver and can lead to liver disease. liver disease has been associated with a reduction in albumin levels in patients. albumin is a crucial protein in humans, primarily responsible for regulating the oncotic pressure of blood, which is vital for maintaining fluid balance in blood vessels and supporting tissue repair. on average, patients with liver disease exhibit a 10 - 30% decrease in blood albumin levels. (a) identify the structure or organelle in liver cells most likely affected by hepatitis c. (b) justify your identification in part (a).

practice mini frq

1. in humans, pancreatic cells synthesize the protein insulin in the endoplasmic reticulum (er). patients diagnosed with type 1 diabetes have immune systems that mistakenly attack their pancreatic cells. consequently, these patients cannot produce the hormone insulin and must take medications to introduce insulin into their bodies. (a) describe the process of insulin production in a normal functioning (non - type 1 diabetes) pancreatic cell, starting from the synthesis of the insulin protein in the endoplasmic reticulum (er) to its secretion out of the cell.

Explanation:

1.

(a)

The rough - endoplasmic reticulum (RER) is most likely affected. Albumin is a protein, and the RER is the site of protein synthesis in cells. Since hepatitis C leads to a decrease in albumin levels, the organelle involved in albumin production (RER) is likely affected.

(b)

Proteins like albumin are synthesized on ribosomes attached to the RER. When hepatitis C attacks liver cells and causes a reduction in albumin production, it is reasonable to assume that the RER, which is responsible for albumin synthesis, is damaged or its function is impaired by the virus.

2.

After insulin is synthesized in the endoplasmic reticulum (ER), it is transported in vesicles to the Golgi apparatus. In the Golgi, insulin undergoes further modifications such as glycosylation and is packaged into secretory vesicles. These secretory vesicles then move to the cell membrane and fuse with it, releasing insulin out of the pancreatic cell into the bloodstream through a process called exocytosis.

Answer:

1.

(a)

The rough - endoplasmic reticulum (RER).

(b)

Albumin is a protein synthesized on the RER. A decrease in albumin levels due to hepatitis C implies damage to the RER.

2.

Insulin synthesized in the ER is transported to the Golgi in vesicles. In the Golgi, it is modified and packaged into secretory vesicles. These vesicles fuse with the cell membrane and release insulin by exocytosis.