Test 2- Ch 6-7 Flashcards
The advantage of light microscopy over electron microscopy is that
Light microscopy provides higher contrast than electron microscopy
The primary objective of cell fractionation is to
Separate the major organelles so that their particular functions can be determined
All the following are part of a prokaryotic cell except
An endoplasmic reticulum
The volume enclosed by the plasma membrane of plant cells is often much larger than the corresponding volume in animals cells. The most reasonable explanation for this observation is that
Plant cells contain a large vacuole that reduces the volume of the cytoplasm
Which of the following is a major cause of the size limits for certain types of cells?
The need for sufficient surface area to support the cells metabolic needs
Which of the following statements concerning cells of bacteria and archaea is correct?
DNA is present in both archaea and bacteria
Procaryotes are classified as belonging in two different domains. What are the domains?
Bacteria and archaea
Large numbers of ribosomes are present in cells that specialize in producing which of the following molecules?
Proteins
A cell with a predominance of free ribosomes is most likely
Producing primarily proteins fo secretion
Which type of organelle or structure is primarily involved in the synthesis of oil’s, phospholipids, and steroids?
Smooth endoplasmic reticulum
Which structure is the site of the synthesis of proteins that may be exported from the cell?
Rough ER
Which of the following contains hydrolytic enzymes
Lysosome
Which organelle is the primary site of ATP synthesis in eukaryotic cells?
mitochondrion
Which plant cell organelle contains it’s own DNA and ribosomes?
Mitochondrion
Which animal cell organelle contains enzymes that transfer hydrogen from various substrates oxygen?
Peroxisome
Thylakoids, DNA, and ribosomes are all components found in
Chloroplasts
In a plant cell, DNA maybe found
In the nucleus, mitochondria, and chloroplasts
Motor proteins provide for molecular motion in cells by interacting with what type of cellular structures?
Cytoskeletal structures
A biologist wants specifically to examine the surfaces of different types of cells and kidney tubules of small animals. The cells in question can be distinguished by external shape, size, and 3-D characteristics. Which of the following would be the optimal method for her study question?
Scanning electron microscopy
It biologist ground up some plant leaf cells and then centrifuged the mixture to fractionate the organelles. Organelles in one of the behavior fractions could produce ATP in the light whereas organelles in the lighter fraction to produce ATP in the dark. The heavier and lighter factions are most likely to contain, respectively,
Chloroplasts and mitochondria
Which structure is common to plant and animal cells?
Mitochondrion
What is the most likely pathway taken by a newly synthesized protein that will be secreted by a cell?
ER –> Golgi –> vesicles that fuze with plasma membrane
Singer and Nicholsons fluid Mosaic model of the membrane proposed that
Membranes consist of protein molecules embedded in a fluid bilayer of phospholipids
Which of the following types of molecules are the major structural components of the cell membrane?
Phospolipids and proteins
The presence of cholesterol in the plasma membranes of some animals
Enables the membrane to say fluid more easily when cell temperature drops
According to the fluid Mosaic model of some membranes, which the following is a true statement about membrane phospholipids?
They can move laterally along the plane of the membrane
In order for protein to be an integral membrane protein it would have to be
Amphipathic, with at least one hydrophobic region
The primary function of polysaccharides attached to the glycoprotein and glycolipids of animal cell membranes is
To mediate cell-to-cell recognition
What kinds of molecules pass through the cell membrane most easily?
Small and hydrophobic
Nitrous oxide gas molecules diffusing across a cells plasma membrane is an example of
Diffusion across the lipid bilayer
Which the following would most likely move through the lipid bilayer of a plasma membrane most rapidly
CO2
Which the following statements is correct about diffusion?
It is a passive process in which molecules move from a region of higher concentration to region of lower concentration
Celery stocks that are immersed in freshwater for several hours become stiff and hard. Similar stalks left in a 0.15 M salt solution become limp and soft. From this we can deduce that
The freshwater is hypotonic and the salt salt solution is hypertonic to the cells of the celery stalks
Mammalian blood contains the equivalent of 0.15 M NaCl. Seawater contains the equivalent of 0.45 M NaCl. What will happen if red blood cells are transferred to seawater?
Water will leave the cells, causing them to shrivel and collapse
When a plant cell, such as one from a peeny stem, is submerged in a very hypotonic solution, what is likely to occur?
The cell will become turgid
Proton pumps are used in various ways by members of every domain of organisms: bacteria, archaea, and eukarya. What does this most probably mean?
Protein gradients across the membrane were used by cells that were the common ancestor of all three domains of life
An organism with a cell wall would most likely be unable to take in materials through
Phagocytosis
White blood cells engulf bacteria through what process?
Phagocytosis
A bacterium engulfed by a white blood cell through phagocytosis will be digested by enzymes contained in
Lysosomes
LOOK AT FIGURE 7.5 page 127
Become familiar with peripheral protein, cholesterol, fiber of extra cellular matrix, micro filament of cytoskeleton, and the location of the glycolipid
