Question

What is the sequence of cell organelles, that a secreted protein would have passed through on its journey out of the cell?
A. Mitochondria → Golgi apparatus→ Cell membrane
B. Cell membrane→ Mitochondria→ Golgi apparatus
C. Golgi apparatus→ Rough endoplasmic reticulum→ cell membrane
D. Rough endoplasmic reticulum Golgi apparatus→ cell membrane

Answer 1

An organelle is a membrane-bound structure located within a cell (think of it as a cell's internal organ). The cytoplasm, a viscous liquid located within the cell membrane that houses the organelles and is the site of most of the action in a cell, contains these organelles. An organelle is a subcellular structure that, like an organ in the body, has one or more distinct duties to do in the cell.

Complete answer:
Option A: The Golgi apparatus is the primary organelle for protein and lipid transport in eukaryotic cells. The Golgi apparatus is the primary organelle for protein and lipid transport in eukaryotic cells. The Golgi processes proteins created by the endoplasmic reticulum before sending them to the cell (ER). Proteins enter the Golgi on the cis side, facing the ER, and exit on the trans side, away from the ER.
So, option A is not correct.
Option B: The protein secreted by a cell is known as secretory protein. These proteins are made by ribosomes attached to the endoplasmic reticulum (rough endoplasmic reticulum). The proteins are then transferred from the rough endoplasmic reticulum to the cis-Golgi apparatus in the form of vesicles, where they are modified, for example, by the addition of sugars.
So, option B is not correct.
Option C: The Golgi apparatus is the eukaryotic cell's major organelle for protein and lipid transport. The Golgi apparatus is the eukaryotic cell's major organelle for protein and lipid transport. Before transferring proteins to the cell, the Golgi processes proteins generated by the endoplasmic reticulum (ER). Proteins enter the Golgi on the cis side of the stack, facing the ER, and exit on the trans side, facing the cell's plasma membrane (trans side).
So, option C is incorrect.
Option D: Secretory protein refers to the protein that a cell secretes. Ribosomes linked to the endoplasmic reticulum produce these proteins (rough endoplasmic reticulum). The proteins are then transported in the form of vesicles from the rough endoplasmic reticulum to the cis-Golgi apparatus, where they undergo various modifications such as the addition of sugars. These proteins are repackaged in vesicles that merge with the cell membrane and are released out of the cell after modification.
Hence option D is correct.

Therefore, Option D is the correct answer.

Note:
The endoplasmic reticulum, Golgi apparatus, and the vesicles that move between them, as well as the cell membrane and lysosomes, are all part of the secretory pathway. It's called a secretory pathway since it's where the cell secretes proteins into the extracellular environment. Proteins that will be membrane-bound (whether in the cellular membrane or in the ER or Golgi membranes themselves), lysosomal enzymes, and any proteins that will live their life in the secretory pathway itself are all processed via this pathway. It does a lot more than only digest proteins.