A cell with a predominance of free ribosomes is most likely A) producing primarily proteins for secretion. B) producing primarily cytoplasmic proteins. C) constructing an extensive cell wall or extracellular matrix. D) digesting large food particles. E) enlarging its vacuole.
2.Which structure is the site of the synthesis of proteins that may be exported from the cell? A) rough ER B) lysosomes C) plasmodesmata D) Golgi vesicles E) free cytoplasmic ribosomes
Which of the following statements correctly describes some aspect of protein secretion from prokaryotic cells? A) Prokaryotes are unlikely to be able to secrete proteins because they lack an endomembrane system. B) The mechanism of protein secretion in prokaryotes is probably the same as that in eukaryotes. C) Proteins that are secreted by prokaryotes are synthesized on ribosomes that are bound to the cytoplasmic surface of the plasma membrane. D) In prokaryotes, the ribosomes that are used for the synthesis of secreted proteins are located outside of the cell. E) Prokaryotes contain large pores in their plasma membrane that permit the movement of proteins out of the cell.
Which of the following produces and modifies polysaccharides that will be secreted? A) lysosome B) vacuole C) mitochondrion D) Golgi apparatus E) peroxisome
Why isn’t the mitochondrion classified as part of the endomembrane system? A) It is a static structure. B) Its structure is not derived from the ER or Golgi. C) It has too many vesicles. D) It is not involved in protein synthesis. E) It is not attached to the outer nuclear envelope.
Centrioles, cilia, flagella, and basal bodies have remarkably similar structural elements and arrangements. Which of the following hypotheses is most plausible in light of such structural similarities? A) Cilia and flagella arise from the centrioles. B) Loss of basal bodies should lead to loss of all cilia, flagella, and centrioles. C) Motor proteins such as dynein must have evolved before any of these four kinds of structure. D) Cilia and flagella coevolved in the same ancestral eukaryotic organism. E) Natural selection for cell motility repeatedly selected for microtubular arrays in circular patterns in the evolution of each of these structures.
When a potassium ion (K+) moves from the soil into the vacuole of a cell on the surface of a root, it must pass through several cellular structures. Which of the following correctly describes the order in which these structures will be encountered by the ion? A) plasma membrane → primary cell wall → cytoplasm → vacuole B) secondary cell wall → plasma membrane → primary cell wall → cytoplasm → vacuole C) primary cell wall → plasma membrane → cytoplasm → vacuole D) primary cell wall → plasma membrane → lysosome → cytoplasm → vacuole E) primary cell wall → plasma membrane → cytoplasm → secondary cell wall → vacuole
Plasmodesmata in plant cells are most similar in function to which of the following structures in animal cells? A) peroxisomes B) desmosomes C) gap junctions D) extracellular matrix E) tight junctions
ECM proteins are made by ribosomes in which part of a eukaryotic cell? A) mitochondria B) cytoplasm C) nuclear envelope D) Golgi apparatus E) rough ER
What is the most likely pathway taken by a newly synthesized protein that will be secreted by a cell? A) ER → Golgi → nucleus B) Golgi →ER →lysosome C) nucleus →ER →Golgi D) ER →Golgi →vesicles that fuse with plasma membrane E) ER →lysosomes →vesicles that fuse with plasma membrane