chapter 6 test
in the nucleus, mitochondria, and chloroplasts.
In a plant cell, DNA may be found
scanning electron microscopy
A biologist wants specifically to examine the surfaces of different types of cells in kidney tubules of small mammals. The cells in question can be distinguished by external shape, size, and 3-D characteristics. Which of the following would be the optimum method for her study?
producing primarily cytoplasmic proteins.
A cell with a predominance of free ribosomes is most likely
an endoplasmic reticulum.
All of the following are part of a prokaryotic cell except
lysosome
Hydrolytic enzymes must be segregated and packaged to prevent general destruction of cellular components. Which of the following organelles contains these hydrolytic enzymes in animal cells?
1. Nucleus 2. Endoplasmic Reticulum 3. Golgi Apparatus 4. Mitochondria Nucleus: The nucleus is a cell organelle consisting of a double membrane that houses DNA. The nucleus's main function is to direct protein synthesis. The nucleus provides the DNA that codes for specific proteins, and therefore provides their functions as well. Endoplasmic Reticulum: Both the Rough and Smooth ER are located with an Animal Cell. The Rough ER is studded with ribosomes, allowing it to aid in the synthesis of proteins. Additionally the organelle modifies the proteins to ensure that it will fulfill its cellular assignment. The Smooth ER synthesizes lipids, oils, steroids and phospholipids within the cell and plays a prominent role in the sexual reproductive system as well as in the liver by detoxifying drugs that enter the body. Golgi Apparatus: The Golgi Apparatus can be considered the warehouse for receiving, sorting, shipping and manufacturing proteins that arrive from the Endoplasmic Reticulum. The Golgi Apparatus consists of flattened membranes that send proteins through the organelle through cis - trans faces. Mitochondria: The Mitochondria are in charge of cellular respiration and eventually will produce ATP to provide the cell with the necessary nutrition and energy needed to survive, thrive, and eventually reproduce through cell division. Mitochondria uses Oxygen to produce this ATP from sugars, fats, etc.
Identify 4 organelles located in an animal cell. Describe their main function within the cell.
1. Tight Junctions 2. Desmosomes 3. Gap Junctions Tight Junction: The tight junction prevents leakage of extracellular fluid throughout the cell because the plasma membrane is tightly compressed and bound by specified proteins that prevent leakage. This explains why humans are watertight individuals. Desmosomes: Also know as anchoring junctions, Desmosomes connect with the cytoplasm and muscles to create strong sheets that in part assist in providing a strong structure for the entire cell. Gap Junction: Gap Junctions provide channels from one cell to adjacent cells in order to assist with cell communication. The proteins that are within the membrane allow small molecules to pass through each cell.
Identify the three cell junctions covered in class. Describe each of their characteristics that allow them to carry out their role.
the size and weight of the component.
In the fractionation of homogenized cells using centrifugation, the primary factor that determines whether a specific cellular component ends up in the supernatant or the pellet is
proteins
Large numbers of ribosomes are present in cells that specialize in producing which of the following molecules?
nuclear envelope
One of the key innovations in the evolution of eukaryotes from a prokaryotic ancestor is the endomembrane system. What eukaryotic organelles or features might have evolved as a part of, or as an elaboration of, the endomembrane system?
endosymbiosis of an aerobic bacterium in a larger host cell - aka a cell engulfed a mitochondria and possibly chloroplast
The evolution of eukaryotic cells most likely involved
plant cells contain a large vacuole that stores water and nutrients and takes up a good amount of space.
The volume enclosed by the plasma membrane of plant cells is often much larger than the corresponding volume in animal cells. The most reasonable explanation for this observation is that
chloroplasts.
Thylakoids, DNA, and ribosomes are all components found in
ER --> Golgi --> vesicles that fuse with plasma membrane
What is the most likely pathway taken by a newly synthesized protein that will be secreted by a cell?
a transmission electronic microscope.
When biologists wish to study the internal ultrastructure of cells, they can achieve the finest resolution by using
mitochondrion
Which organelle is the primary site of ATP synthesis in eukaryotic cells?
vacuole
Which organelle often takes up much of the volume of a plant cell?
mitochondrion
Which plant cell organelle contains its own DNA and ribosomes?
rough ER
Which structure is the site of the synthesis of proteins that may be exported from the cell?
smooth endoplasmic reticulum
Which type of organelle or structure is primarily involved in the synthesis of oils, phospholipids, and steroids?