Light microscopes...
use light and glass lenses to magnify an image
Resolution is...
Ability of an optical instrument to show two close objects as separate
Which of the following statements about electron microscopes is true?
Electron microscopes focus electron beams to create a magnified image of an object
A scientist wants to examine living cells lining the respiratory tract to determine how the cells use tiny hairs to move dirt and mucus away from the lungs. Which of the following instruments would be best, and why?
A light microscope because it allows observations of whole, live cells
Cell theory states that...
all living things are composed of cells and that all cells come from other cells
A scientist wants to magnify a pollen grain 8,000 times and examine the ridges and pores on its surface. Which one of the following instruments would be best?
A scanning electron microscope
A scanning electron microscope is used to study ----- , whereas a transmission microscope is used to study----
cell surfaces; internal cell structures
As cell size increase, the
volume increases proportionally more than the surface area
A cell is exposed to a substance that prevents it from dividing. The cell becomes larger and larger. This situation
will eventually be problematic since the cell's ability to absorb nutrients through its outer membrane will not increase as quickly as its cytoplasmic needs
Your throat is dry, and you want the last cough drop in the box to last a long time in your mouth. What should you do?
Keep the cough drop whole. This maintains the largest surface-to-volume ratio and slows the dissolution of the last cough drop.
A pathologist who wants to examine a patient's liver cells to determine if the mitochondria have an internal structural defect will likely need to use a
transmission electron microscope
In the plasma membrane, the phospholipid heads
are hydrophilic and face outward toward the aqueous solution on both sides of the membrane.
The nucleoid region of a prokaryotic cell
contains the cell's DNA
#NAME?
Prokaryotic
You are told that the cells on a microscope slide are plant, animal, or bacterial. You look at them through a microscope and see cell walls and membrane-bound organelles. You conclude correctly that the cells
are plant cells
Unlike animal cells, plant cells have ________ and ________. Unlike plant cells, animal cells have ________.
chloroplasts; cell walls; centrioles
Which of the following statements about cellular metabolism is false?
Cellular metabolism occurs in animal but not plant cells
The nucleus of a cell
contains DNA
The complex of proteins and DNA in a non-dividing cell is called
chromatin
During cell reproduction, chromatin fibers coil up into structures called
chromosomes
The function of the nucleolus is
to manufacture ribosomal RNA
Which of the following statements regarding the endomembrane system is false?
The endomembrane system is a system of interrelated membranes that are all physically connected
An immune system cell called the plasma cell produces thousands of antibodies (a type of protein) per second for release into the body. What type of intracellular structure would you expect to be very prominent within the cell?
the rough endoplasmic reticulum
The main function of the endoplasmic reticulum is the production of
membrane and proteins secreted by the cell
The cells that produce hair made of proteins contain a lot of -------, while the cells that produce the oils that coat the hair contain a lot of --------
rough endoplasmic reticulum; smooth endoplasmic reticulum
The Golgi apparatus
stores, modifies, and packages proteins
Which of the following statements regarding the Golgi apparatus is false?
The Golgi apparatus decreases in size when a cell increases its protein production
Which of the following statements about lysosomes is false?
Lysosomes synthesize proteins from the recycled amino acids
Which of the following statements about the functions of a plant cell central vacuole is false?
The central vacuole of a plant cell may digest chemicals for recycling
Contractile vacuoles...
prevent cells from bursting by pumping out excess water
A manufacturing company dumps its wastes into a nearby pond. One of the wastes is found to paralyze the contractile vacuoles of certain protists. A biologist looking at individual samples of these organisms taken from the pond would find that they...
have gained water and burst
Which organelle is involved in the breakdown of the fatty acids and the detoxification of alcohol?
Peroxisome
Insulin is a protein that is produced by pancreatic cells and secreted into the bloodstream. Which of the following options correctly lists the order of the structures through which insulin passes from its production to its exit from the cell?
Rough ER, transport vesicles, Golgi apparatus, transport vesicles, cell membrane
The function of a mitochondria is
cellular respiration
Cyanide inhibits mitochondrial function; as a result, the rate of
ATP synthesis decreases
The ------ of a mitochondrion is/are an adaptation that increases the surface area and enhances a mitochondrion's ability to produce ATP
cristae
The function of chloroplasts is
photosynthesis
Mitochondria differ from chloroplasts in that mitochondria
contain membrane folds called cristae, whereas chloroplasts contain disklike vesicles in stacks called grana
The endosymbiosis hypothesis proposes that....
a small cell lived inside a larger cell to the benefit of both cells
Microfilaments differ from microtubules in that microfilaments...
are mainly composed of actin, whereas microtubules are composed of tubulin
A drug that interferes with microtubule formation is likely to completely disrupt
the movements of sperm cells
Cilia differ from flagella in that
cilia are typically more numerous and shorter than flagella
Which of the following would be most affected by a mutation that prevented cells from forming tight junctions?
integrity of the inner lining of the digestive tract
Skin cells are fastened into strong sheets by
anchoring junctions
It is essential for heart muscle cells to beat in a coordinated fashion. The cell junctions that would best facilitate this are
gap junction
Which of the following statements regarding plasmodesmata is false?
Plasmodesmata are found in plants and animals
Which of the following cell structures are associated with the breakdown of harmful substances (detoxifying the cell)?
peroxisomes
Which of the following statements regarding cells is false?
All cells have a cell wall
A child dies following a series of chronic bacterial infections. At the autopsy, the physicians are startled to see that the child's white blood cells are loaded with vacuoles containing intact bacteria. Which of the following explanations could account for this finding?
A defect in the lysosomes of the white blood cells prevented the cells from destroying engulfed bacteria