Eukaryotic Cells Flashcards
What is an organelle?
An organelle is a small structure within a cell that carries out specific cellular functions.
What is the nucleolus?
The nucleolus is a region within the nucleus which functions as a ribosome Factory
Is there a membrane separating the nucleolus from the rest of the nucleus?
No. There is no membrane separating the nucleolus from the rest of the nucleus
Would you expect the nucleolus to be larger in cells that are actively synthesized in protein or in quiescent cells?
The nucleolus is larger in the cells that are producing large amounts of protein. The increased size reflects increase synthesis of ribosomes.
What role would the loops of DNA in the nucleolus play?
The DNA will serve as template for ribosomal RNA production.
Is the space between the inner and outer nuclear membranes contiguous with the cytoplasm?
No it is not. The space between the nuclear membranes is contiguous with the ER Lumen which is isolated from the cytoplasm
Proteins translated on free cytoplasmic ribosomes are headed towards where?
They are headed towards peroxisomes mitochondria the nucleus or will remain in the cytoplasm.
Where will proteins synthesized on the rough ER and up?
They will either be secreted into the extracellular environment or as integral plasma membranes or in the membrane of the interior of the ER Golgi apparatus or lysosomes.
The mRNA for a secreted protein includes a longer protein than is actually observed in this cellular exterior. Why?
A) the protein was cleared by a cytoplasmic protease
B) the mRNA was not spliced properly
C) the gene encoding a protein contained a nonsense mutation
D) the signal sequence of the protein was removed in the rough ER
D.
A vesicle fusion with the Cisco LG was inhibited the plasma membrane proteins still reach the cell surface?
No. Secretory proteins must proceed by a specific path from the ER to the Cisco Golgi to the medial and trans Golgi and from there to the cell surface
Acid hydrolysis
The enzymes responsible for degradation and lysosomes
What enzymes found in peroxisomes gets rid of the hydrogen peroxide buy a
Catalase
Convert hydrogen peroxide to water and oxygen
What is molarity?
Molarity expresses the concentration of a solution in terms of moles of solute per volume in litres of solution
What is a karyotype?
A karyotype is display of the organism’s genome
Cell mitosis will not begin until the entire genome is replicated. If this inhibition is removed so that mitosis begins during S phase which of the following will occur?
A) the cells would grow more quickly
B) the genome would become fragmented and incomplete
C) the cells with display unregulated cancerous growth
D) The genome would be temporarily and complete in each daughter cell but DNA repair will fill in the missing gaps
B
