MB chapter 6
What name is given to the rigid structure, found outside the plasma membrane, that surrounds and supports the bacterial cell?
cell wall
_____ are found only in plant cells, but _____ are found in both plant and animal cells.
central vaculoles, ribosomes
Plant cells have two energy-related organelles. ________________ harness light energy to create sugars and ________________ break down these sugars to create ATP. Plant cells have two energy-related organelles. ________________ harness light energy to create sugars and ________________ break down these sugars to create ATP.
chloroplasts, mitrochondria
the _____ is composed of DNA and protein.
chromatin
The primary role of _____ is to bind animal cells together.
desmosomes
Many cell organelles, most notably the nucleus, are anchored by which are assembled from a diverse class of proteins.
intermediate filaments
The only cytoskeletal fibers not associated with intracellular movement or whole cell locomotion are the
intermediate filaments
Which of these organelles carries out cellular respiration?
mitrochondrion
Which of these organelles produces H2O2 as a by-product?
peroxisome
Which of the following is a function of the central vacuole?
storing compounds produced by the cell
the diameter of a typical eukaryotic cell is approximately ten times the diameter of a typical prokaryote. What is the ratio of the volume of typical eukaryotic:prokaryotic cells
1000:1
all proteins are synthesized by ribosomes in the cell. Some ribosomes float freely in the cytosol, while others are bound to the surface of the endoplasmic reticulum. Most proteins made by free ribosomes function in the cytosol. Proteins made by bound ribosomes either function within the endomembrane system or pass through it and are secreted from the cell. Which of the following proteins are synthesized by bound ribosomes?
2. ER protein 4. insulin 6.lysosomal enzyme -Most proteins that function in the cytosol (such as actin) or in the nucleus (such as DNA polymerase) are synthesized by free ribosomes. Proteins that function within the endomembrane system (such as lysosomal enzymes) or those that are destined for secretion from the cell (such as insulin) are synthesized by bound ribosomes. As a protein destined for the endomembrane system is being synthesized by a ribosome, the first amino acids in the growing polypeptide chain act as a signal sequence. That signal sequence ensures that the ribosome binds to the outer membrane of the ER and that the protein enters the ER lumen.
What path does a protein in the secretory pathway take, starting from its site of synthesis?
Rough ER, Golgi apparatus, secretory vesicles, plasma membrane
Which of the following functions is NOT associated with the cytoskeleton in eukaryotic cells?
Movement of RNA molecules from the nucleus to the cytoplasm
During a pulse-chase experiment, photographic emulsions were prepared at different times during the chase, and radioactive spots were detected at the following times and locations: 5 minutes: rough ER; 10 minutes: Golgi apparatus; 40 minutes: endosomes; 70 minutes: lysosomes; 140 minutes: lysosomes. Which of the following conclusions can be drawn from these results?
The final destination of the proteins was the lysosome.
Fimbriae
are surface appendages that allow a bacterium to stick to a surface.
___ is/are identical in structure to centrioles.
basal bodies
Basal bodies are most closely associated with which of the following cell components?
cilia
Which of the following describes the function of the chloroplast?
converts light energy to chemical energy
_____ aid in the coordination of the activities of adjacent animal cells.
gap junctions
Which of the following is part of the endomembrane system?
golgi apparatus
What is the first step in a pulse-chase experiment?
incubating cells with labeled molecule
Which organelle plays a role in intracellular digestion
lysosome
Which of the following organelles breaks down worn-out organelles?
lysosomes
During muscle contractions, myosin motor proteins move across tracks o
microfilaments
The extension of pseudopodia in amoeba is due to the regulated assembly and destruction of
microfilaments
Centrosomes are sites where protein dimers assemble into
microtubules
In eukaryotic flagella, the fibers that slide past one another due to the activity of dynein proteins are
microtubules
The cilia and flagella of eukaryotic cells are composed of _____.
microtubules
which of these are hollow rods that shape and support the cell?
microtubules
Which plant cell organelle converts chemical fuel into packets of chemical energy that can power the cell?
mitrochondrion
Where is a bacterial cell's DNA found?
nucleoid region
Ribosomal subunits are manufactured by the _____.
nucleolus
The _____ is a selective barrier, regulating the passage of material into and out of the cell
plasma membrane
The _____ is the bacterial structure that acts as a selective barrier, allowing nutrients to enter the cell and wastes to leave the cell.
plasma membrane
Two fundamental types of cells are known to exist in nature: prokaryotic cells and eukaryotic cells (like the one shown in the Tour of an Animal Cell animation). Both prokaryotic and eukaryotic cells carry out all of the processes necessary for life, but they differ in some important ways. In this activity, you will identify which cell structures are found only in prokaryotic cells, only in eukaryotic cells, or in both types of cells. Drag each cell structure to the appropriate bin.
prokaryotic only: nucleoid eukaryotic only: nucleolus, lysosome, mitochondria both: plasma membrane, ribosomes, flagelia
What is the function of a bacterium's capsule?
protection
The pathway of secretory proteins Proteins that are secreted from a eukaryotic cell must first travel through the endomembrane system.
protein synthesis->endoplasmic reticulum-> cis golgi cisternae->medial golgi cisternae ->trans golgi cisternae->plasma membrane ->extracellular space As they are being synthesized, secretory proteins enter the lumen of the endoplasmic reticulum. From the ER, vesicles transport these proteins to the Golgi, where they are sequentially modified and concentrated in a cis-to-trans direction. Secretory vesicles bud from the Golgi and move along cytoskeletal filaments to eventually fuse with the plasma membrane, secreting their protein cargo. Each of these transport steps requires specialized proteins to ensure that the cargo is sent to the proper location and is able to fuse with the target membrane.
In a bacterium, where are proteins synthesized?
ribosomes
_____ are the sites of protein synthesis.
ribosomes
Which of the following features do prokaryotes and eukaryotes have in common?
ribosomes, plasma membrane, cytoplasm
Which of these organelles manufactures proteins bound for secretion out of the cell?
rough ER
Where are lipids made in the cell?
smooth ER
Where is calcium stored?
smooth ER
Which of these cell junctions form a barrier to the passage of materials
tight junctions
Beginning within the nucleus, the first step leading to the synthesis of a polypeptide is _____.
transferring of info from DNA to mesanger RNA