BS 161 Chapter 4 Homework – Flashcards
Unlock all answers in this set
Unlock answersquestion
As a cell increases in size the surface area increases ______ than the volume.
answer
less
question
The surface area of a cell increases proportionally to the radius _________.
answer
squared
question
The volume of a cell increases proportionally to the radius _______.
answer
Cubed
question
Understanding the surface area to volume relationship, a basketball has a __________ surface area to volume ration compared to a tennis ball.
answer
Smaller
question
Contains instructions for protein synthesis and cell reproduction; contains genetic information
answer
Nucleus
question
Intracellular compartment forms transport vesicles; participates in lipid synthesis and synthesis of membrane or secreted proteins.
answer
Endoplasmic reticulum
question
Packages proteins for export from cells; forms secretory vesicle
answer
Golgi apparatus
question
Digest worn-out organelles and cell debris; digest material taken up by endocytosis
answer
Lysosomes
question
Carries out a variety of functions including regulating water levels in plant cells.
answer
Vacuole
question
Involved in the breakdown of fats and contains that enzyme catalase.
answer
Peroxisome
question
Tay-Sachs disease causes lysosomes to rupture. How would this affect the cell?
answer
Phagocytic cells would not destroy bacteria.
Material taken up through endocytosis would not be digested.
Biological polymers would not be broken down by lysosomes.
question
Lysosomes are membrane-bound vesicles that arise from the _________
answer
Golgi apparatus
question
The lysosome contains ________ enzymes.
answer
Hydrolytic
question
There has been a mutation that has deleted a gene responsible for the formation of vesicles at the trans end of the Golgi apparatus. What effect will this have on the function of lysosomes?
answer
Lysosomes will not form, because they arise as vesicles from the trans end of the Golgi apparatus.
question
A mutation arises in a gene that codes for a lysosomal hydrolytic enzyme. The mutation changes an amino acid in the active site of the enzyme so the enzyme doesn't function properly. What effect might this mutation have on lysosome function?
answer
The lysosome will not be able to digest certain molecules.
question
You are doing a study on the effects of lysosomal enzymes and want to follow the whole process from the formation of the enzymes to their use in the lysosome. In what location of the cell would you begin this observation?
answer
Endoplasmic reticulum
question
How did mitochondria and chloroplasts most likely arise?
answer
They arose from bacteria that were engulfed and not digested. Mitochondria are thought to have arisen from aerobic bacteria, and chloroplasts from photosynthetic bacteria. This explains their double membrane and own chromosomes.
question
According to endosymbiosis theory, what is the most likely explanation for the origin of the two mitochondrial membranes?
answer
The inner membrane was derived from folding of the prokaryotic plasma membrane, and the outer from folding in of the eukaryotic plasma membrane.
question
The protein Ras is involved in 25% of all cancers, and is attached to membranes through a covalent bond to a phospholipid. How does Ras associate with membranes?
answer
Through an anchor. The phospholipid to which Ras is attached acts as an anchor, tethering Ras to the membrane.
question
Why does a human red blood cell lyse when placed in a hypotonic solution while a plant cell does not?
answer
The cell wall of the plant prevents the membrane from swelling too much.
question
When you breathe, oxygen moves from your lungs into your blood and then into tissues. To do this, oxygen moves across membranes by ______ and from ______ concentration of oxygen.
answer
Diffusion, higher to lower
