Exam 3 Flashcards
The advantage of light microscopy over electron microscopy is that
Light microscopy allows one to view dynamic processes in living cells
Ions can travel directly from the cytoplasm of one animal cell to the cytoplasm of an adjacent cell through
Gap junctions
Plasmodesmata in plant cells are most similar in function to which of the following structures in
Gap junctions
Ions can travel directly from the cytoplasm of one animal so to the cytoplasm of an adjacent so true
Gap junctions
In the fractionation of homogenized sells using since your fusion the primary factor that determines whether a specific cellular component ends up in the supernatant or the pallet is the
Size and weight of the component
What technique would be most appropriate to use to observe the movements of condensed chromosomes during cell division?
Standard light microscopy
Which of the following is a major difference between prokaryotic cells and eukaryotic cells?
Eukaryotic cells have more intracellular organelles than prokaryotes
What produces an modifies polysaccharides that will be secreted
Golgi apparatus
What contains hydrolytic enzymes
Lysosome
What helps to recycle the cells organic material
Lysosome
What is one of the main energy transformers of cells
Mitochondrion
White blood cells engulf bacteria through what process?
Phagocytosis
What is the cause of familial hypercholesterolemia?
Defective LDL receptors on the cell membranes
The difference between Pinot cytosis and receptor mediated endocytosis is that
Pinocytosis brings only water into the cell, but receptor mediated endocytosis brings in other molecules as well
And hypotonic solution and animal cell will
Lyse
A membrane that allows only certain molecules to pass through it is called a___
Selectively permeable
The random movement of like molecules or ions from an area of high concentration to an area of low concentration is called
Simple diffusion
During osmosis____moves across the cell membrane
Water
Water diffuses across a selectively permeable membrane down a potential gradient from a___
Hypotonic solution to a hypertonic solution
If a red blood cells and a plant cell or placed in distilled water, water will move into the red blood cells into the red blood cell____and into the plant cell until the plant cell____
Burst; develops enough turgor to oppose movement of water
The movement of water across a selectively permeable membrane in response to a concentration gradient exerts a force called
Osmotic pressure
If a reason his place in concentrated sugar water, water will move___into the raisin in the sugar water surrounding the reason is said to be ____ with respect to the inside of the raisin
Into; hypotonic
One plant cells are exposed to a hypotonic solution they____and exhibit the phenomenon
Expand; turgor pressure
And plant cells are exposed to a hypertonic solution they___and exhibit the phenomenon called
Shrink; plasmolysis
Which of the following mechanisms of membrane transport requires the expenditure of ATP by the cell
Active transport
Which of the following mechanisms of membrane transport moves molecules against a concentration gradient?
Active transport
Facility diffusion of glucose requires
A membrane protein carrier
Cells take in large amounts of material by fusing parts of the membrane around the material. This process is called
Phagocytosis
Cells taken small amounts of soluble material by forming in word folds of the membrane. This process is called
Pinocytosis
The process that sells used to expel small amounts of material by placing them in membrane vesicles and fusing the vesicles to the plasma membrane is called
Exocytosis
The small channels that plant cells have through which molecules can pass from one plant cell to it’s neighbor are called
Plasmodesmata
Which of the following describes some aspect of metabolism
A, B, and C
Which term most precisely describe the cellular process of breaking down large molecules into smaller ones
Catabolism
Which of the following statements correctly describe Catabolic pathways
They release energy as they degrade polymers to monomers
Which of the following is a statement of the first law of thermodynamics
Energy cannot be created or destroyed
The first law of thermodynamics states that energy can be neither created nor destroyed. For living organisms, which of the following is an important consequence of the first law
The organism ultimately must obtain all the necessary energy for life from its environment
According to the first law of thermodynamics
Energy can be neither created nor destroyed
Whenever energy is transformed, there is always an increase in the
Entropy of the universe
Which of the following forms of energy is least available to accomplish cellular work?
Thermal energy, heat
Chemical reaction that has a positive G is correctly described as
Endergonic
Why is ATP an important molecule in metabolism
It provides energy coupling between exergonic and endergonic reactions
An enzyme catalyzes a reaction by
Lowering the energy of activation of a reaction
What is a non-protein helper of an enzyme molecule called?
Coenzyme
Zinc, an essential trace element for most organisms, is present in the active site of the enzyme carboxypeptidase. The Tzanck most likely functions as a
Cofactor necessary for enzyme activity
The mechanism in which the end product of a metabolic pathway inhibits a earlier step in the pathway known as
Feedback inhibition
How does a noncompetitive inhibitor or decrease the rate of an enzyme reaction?
By changing the structure of the enzyme
choose the pair of terms that correctly complete this sentence
Exergonic; Endergonic
Increasing the substrate concentration in an enzymatic reaction could overcome which of the following?
Competitive inhibition
Most cells cannot harness heat to perform work because
Temperature is usually uniform throughout a cell
According to the first law of thermodynamics
Energy is conserved in all processes
Which of the following metabolic processes can occur without a Net influx of energy from some other process?
C6H12O6 + 6 O2 → 6 CO2 + 6 H2O
In a bacterium, we will find DNA in
The nucleoid
Which organelle or structure is absent in plant cells
Centrosomes
What is the function of the nuclear pore complex found in eukaryotes
It regulates the movement of proteins and RNA into and out of the nucleus
Which organelle is the primary site of ATP synthesis in eukaryotic cells
Mitochondrion
Which of the following is not true? Both chloroplasts and mitochondria
Are apart of the endomembrane system
Which of the following produces in modifies polysaccharides that will be secreted
Golgi Apparatus
What is most likely pathway taken by a newly synthesized protein that will be secreted by a cell
ER–>Golgi–>vesicles that fuse with plasma membrane
Tay-Sachs diseases that human genetic abnormality that results in cells accumulating and becoming clogged with a very large complex and I just and lipids, which cellular organelle must be involved in this condition?
The lysosome
The liver is involved in detoxification of many voices and drugs. Which of the following structures is primarily involved in this process and, therefore, abundant in liver cells?
Smooth ER
