Which membranous organelle is the site of protein synthesis for proteins that are secreted by the cell?
Contents in week 3
| Question | Answer |
|---|---|
| A major function of the cell membrane is to | Control what enters and leaves the cell. |
| Which of the following is not a cytoskeleton element? | Centriole |
| This membranous organelle is the site of protein synthesis for proteins that are secreted by the cell. | Rough ER |
Which organelle contains circular DNA molecule and is capable of self replication?
Mitochondria are self-replicating organelles that occur in various numbers, shapes, and sizes in the cytoplasm of all eukaryotic cells.
Which organelle is characterized by folded inner membranes called Cristae?
Mitochondria are oval-shaped, double-membrane organelles (Figure 3.17) that have their own ribosomes and DNA. Each membrane is a phospholipid bilayer embedded with proteins. The inner layer has folds called cristae, which increase the surface area of the inner membrane.
Which of the following is not a cytoskeleton element?
Cell Structure
| Question | Answer |
|---|---|
| Which of the following is not a cytoskeleton element? | centriole |
| Phospholipids of the plasma membrane are arranged | as a bilayer with their nonpolar tails sandwiched between the polar heads. |
| This organelle has both a cis and a trans face. | Golgi apparatus |
Which organelle synthesizes actin and myosin?
Which cell component synthesizes actin and myosin? Free ribosomes.
Which of the following membrane enclosed organelles is the site of synthesis of membrane proteins and secretory proteins?
the ER
In addition to its activities in the processing of secreted and membrane proteins, the ER is the major site at which membrane lipids are synthesized in eukaryotic cells.
What organelle are proteins made?
ribosomes
Proteins are assembled at organelles called ribosomes. When proteins are destined to be part of the cell membrane or exported from the cell, the ribosomes assembling them attach to the endoplasmic reticulum, giving it a rough appearance.
What are the folds of the outer membrane is called?
Each mitochondrion has two membranes: an inner membrane which is highly convoluted and folded into finger-like projections called cristae, and a smooth outer membrane that is a selective barrier to molecules from the cytoplasm.
Which of the following organelles would form a membrane-bound package also known as a vesicle?
Which of the following organelles would form a membrane-bound package, also known as a vesicle? condensed vesicles. Where do the vesicles that are being made for secretion from the cell become modified and packaged?
Is actin a microtubule?
Microtubules are the largest type of filament, with a diameter of about 25 nanometers (nm), and they are composed of a protein called tubulin. Actin filaments are the smallest type, with a diameter of only about 6 nm, and they are made of a protein called actin.
What is actin and myosin?
The main difference between actin and myosin is that actin is a protein that produces thin contractile filaments within muscle cells, whereas myosin is a protein that produces the dense contractile filaments within muscle cells.
How does myosin bind to actin?
The globular heads of myosin bind actin, forming cross-bridges between the myosin and actin filaments. The (more…) In addition to binding actin, the myosin heads bind and hydrolyze ATP, which provides the energy to drive filament sliding.
Which organelle makes the proteins that are needed by the cell cell membrane Golgi apparatus ribosomes nucleus?
The endoplasmic reticulum (ER)
The endoplasmic reticulum (ER) is a membranous organelle that shares part of its membrane with that of the nucleus. Some portions of the ER, known as the rough ER, are studded with ribosomes and are involved with protein manufacture.
What is the sequence of organelles that a secreted protein would have passed through on its journey out of a cell?
It’s called a secretory pathway since it’s where the cell secretes proteins into the extracellular environment.
What organelle transports proteins and other materials around the cell?
The Endoplasmic Reticulum
The Endoplasmic Reticulum or ER is an extensive system of internal membranes that move proteins and other substances through the cell. The part of the ER with attached ribosomes is called the rough ER. The rough ER helps transport proteins that are made by the attached ribosomes.
What organelles help make and transport proteins and other molecules?
The endoplasmic reticulum (ER) is an organelle responsible for making both membranes and their proteins. It also aids molecular transport through its own membrane.
What is chromatin in biology?
Chromatin refers to a mixture of DNA and proteins that form the chromosomes found in the cells of humans and other higher organisms. Many of the proteins — namely, histones — package the massive amount of DNA in a genome into a highly compact form that can fit in the cell nucleus. Chromatin.
What is the difference between extended chromatin and chromatin?
Chromatin is composed of DNA wound around proteins known as actin. T/F Extended chromatin is tightly wound around histones. T/F This organelle is involved in production of cellular energy. When a phagocytic white blood cell ingests a foreign bacterial cell, the vesicle fuses with this organelle.
What is the difference between true and false chromatin?
True Chromatin is composed of DNA wound around proteins known as actin. True False False Extended chromatin is tightly wound around histones.
What is the mass of histones and chromatin?
The histones are extremely abundant proteins in eukaryotic cells; together, their mass is approximately equal to that of the cell’s DNA. In addition, chromatin contains an approximately equal mass of a wide variety of nonhistone chromosomal proteins.