While abundant quantities of proteins are produced by free ribosomes in the cytosol, new proteins are also produced by which organelle?
A) lysosomes
B) the Golgi apparatus
C) the nucleolus
D) mitochondria
Mitochondria
Which cell would be best for studying lysosomes?
A) Muscle cell
B) Nerve cell
C) Bacteria cell J
D) Phagocytic white blood cell
Phagocytic white blood cell
Disruption of nuclear pore complexes will most likely interfere with transport of what out of the nucleus?
• A) DNA
• B) amino acids
• C) mRNA
Plasmamembrane
-Nucleus
Cytoplasm
• D) phospholipids
mRNA
Which are members of the inter membrane system?
A) nucleus,, mitochondria, peroxisome
• B) nucleus, endoplasmic reticulum,
Golgi apparatus, cell membrane
• C) mitochondria, cell wall, flagella
• D) Golgi apparatus, DNA, RNA, protein
Nucleus, endoplasmic reticulum, Golgi apparatus, cell membrane
What best describes a characteristic of integral membrane proteins?
A) They are hydrophilic.
B) They are hydrophobic.
C) They are amphipathic, with at least one hydrophobic region.
Amphipathic -
D) They are localize Molecules with membrane.
They are amphipathic, with at least one hydrophobic region.
In which way do eukaryotic cell membranes vary?
A)Phospholipids are found only in certain membranes
B) Certain proteins are unique to each membrane
C)Only certain membranes of the cell are selectively permeable
D)Some membranes have hydrophobic surfaces exposed to the cytoplasm while others have hydrophilic surfaces facing the cytoplasm
Certain proteins are unique to each membrane
Which molecules diffuse through a cell membrane most readily?
A) large hydrophobic molecules
B) small hydrophobic molecules
C) large polar molecules
D) small ionic molecules
Small hydrophobic molecules
The force driving simple diffusion is ________, while the energy source for active transport is ________.
A) a concentration gradient; ADP
B) a concentration gradient; ATP hydrolysis
C) transmembrane pumps; an electrochemical gradient
D) phosphorylated carrier proteins; ATP
A concentration gradient; ATP hydrolysis
What best describes the difference between pinocytosis and receptor-mediated endocytosis?
A) Pinocytosis only brings water molecules into the cell, but receptor mediated endocytosis brings other molecules as well
B) Pinocytosis increases the surface area of the plasma membrane, whereas receptor mediated endocytosis decreases the plasma membrane surface area
C) Pinocytosis is non-selective in the molocules it brings into the cell, whereas receptor mediated endocytosis offers more selectivity
D) Pinocytosis can concentrate substances from the extracellular fluid, but receptor mediated endocytosis cannot
Pinocytosis is nonselective, whereas receptor-mediated endocytosis is selective.
A cell is structured such that…
Organelles and membrane proteins are localized to enable specific cellular functions that define the type of cell.
Difference between prokaryotic and eukaryotic cells?
Prokaryotes lack membrane-bound organelles and a nucleus; eukaryotes have both.
Where is DNA located in prokaryotic cells?
In the nucleoid region.
Function of the nucleoid?
Contains the cell’s genetic material and controls cellular activity.
Function of nuclear pores?
Regulate transport of RNA and proteins between nucleus and cytoplasm.
Role of mitochondria?
Produce ATP through cellular respiration.
Which cells have mitochondria?
Eukaryotic cells only.
What is the endomembrane system?
A network of membranes that synthesize, modify, and transport proteins and lipids.
Which organelles are part of the endomembrane system?
Nucleus, ER, Golgi apparatus, lysosomes, vesicles, plasma membrane.
Where does protein translation begin?
On ribosomes in the cytosol or rough ER.
What determines whether a ribosome binds to rough ER?
A signal peptide on the growing protein.
Role of rough ER?
Synthesizes proteins for secretion, membranes, or organelles.
Role of smooth ER?
Lipid synthesis, detoxification, calcium storage.
Function of the Golgi apparatus?
Modifies, sorts, and ships proteins.
How are proteins delivered after Golgi processing?
In transport vesicles to their target destination.
