Test #2
cells that experience high mechanical stress, like heart cells, typically connect to one another using a ___ junction allowing stress to be evenly distributed to a larger area.
anchoring
A cell you view under a microscope has a cell wall but no nucleus. The cell you are viewing could be a
bacterium
all steroid hormones derive from
cholesterol
All steroid hormones are hydrophobic. Where would you expect the receptor proteins for these hormones to be located? In the ____ of a cell.
cytoplasm
The fragrance of bread baking in a kitchen spread to other rooms by
diffusion
Cells in the liver typically acquire cholesterol by receptor-mediated
endocytosis
You observe a vesicle moving toward the plasma membrane from inside of a cell. Once it reaches and fuses with the plasma membrane, you will most likely see and example of
exocytosis
a membrane that is selectively permeable causes damage to the cell by allowing solutes to enter and leave the cell indiscriminately
false
mitochondria produce most of the energy used in a bacteria cell. True or False?
false
steroids are unable to cross plasma membrane
false
the subunits of eukaryotic ribosomes are 30s and 50s
false
To coordinate the contraction of the numerous muscle cells that form the hear, signals must travel rapidly between muscle cells.In order to allow this rapid communication, muscle cells in the heart are connected by
gap junctions
Insulin is produces only by a single organ the pancreas yet insulin is used to move glucose from the blood stream into cells and all over the body. What aspect of hormones makes it possible for insulin to work throughout the body.
hormones are long-range signaling molecules
you observe a cell swelling until it bursts. you just saw
hypotonic solution
signaling molecules can affect a cell from the outside by interacting with specific receptors that are located
in the plasma membrane
When the solute concentration outside of a cell is equal to the solute concentration inside of the cell, the cell is an_____ solution
isotonic
Which of the following is not a function of the plant vacuole
productions of ATP
Ribosomes a very small non membranous organelles associated with the synthesis of
protein
The membrane known as the ____ contains light capturing pigments like chlorophyll
thykaloid
Epithelial tissue in animals provides a barrier against the invasion of bacteria into they body. Which of the following is most likely responsible for creating tight enough barrier to prevent the passage bacteria
tight junctions
Which of the following structures is not found in all types of cells
nucleus
the_____ has a double membrane but no cristae
nucleus
The passive moment of water across a selectively permeable membrane is called
osmosis
During the process of _____ is given off as a by-product
oxgen
change shape upon binding to specific external molecules and then release the molecule on the other side of the membrane
passive carrier proteins
a white blood cell at the site of a puncture wound engulfs a large cluster of bacteria this is an example of
phagocytosis
What components of the plasma membrane of an animal cell would you find at its innermost surface directly exposed to the cytoplasm
phospholipid heads and proteins
The boundary structure that physically defines a cell is the
plasma membrane
Which of the following are found in plants
plasmodesmata
Which of the following would supply energy directly to an active carrier protein
ATP
Which of the following statements is false
Actin filaments define the paths for vesicle movement with the cell
Which of the following statements is false ?
Eukaryotes use RNA as the hereditary genetic material
bind to cell surface receptors and do not enter cells
Hydrophilic signaling molecules
Protist use cilia to move within their habit, but ciliated human cells like those in the bronchi are always anchored to one another and to an extracellular matrix; what benefit does cilia provide these cells?
all of the above
Using an electron microscope you notice an organelle that consists of stacks of membranes and appears to be producing vesicles. This organelle is most likely
a Golgi apparatus
The inner membranes of both mitochondria and chloroplasts are folded into various arrangements. What is the advantage of having a folded membrane rather than a simple interior membrane that follows the same oval shape as the exterior membrane
The folds allow for more surface area for the chemical reaction that occur across the inner membranes
Imagine examining a cell using a light microscope; a prokaryote could be distinguished from a eukaryote by the absence of
a nucleus
Which of the following statements is false?
The plasma membrane is the storehouse for each cells genetic information
is the where lipids destined for other cellular compartments are manufactured
The smooth endoplasmic reticulum
Which of the following statements is true of chloroplasts
They capture energy from sunlight
The plasma membrane of a cell and the membrane boundaries of organelles such as mitochondria and chloroplasts serve similar functions. What is one of the main functions of the membranes of both cells and organelles?
They keep reactants near each other to speed biological reactions
Which of the following would be the best analogy for the function of the Golgi Apparatus
a worker in a factory who places labels on products and then packs them into a shipping box
Muscle cells require high concentrations of calcium to function properly. As a result, the cells use ________ transport to move calcium from areas of low concentration outside the cell into the cytoplasm
active
the concentration of glucose inside of a cell is higher than the concentration outside of that cell, yet glucose continues to enter the cell. This is an example
active transport
The relative abundance of a specific organelle is often predictable when cell function is considered; for example, the _____ could be expected to contain more lysosomes than an average cell
cell that roam around your body engulfing and consuming bacteria
Which of the following components contribute to the structure of the cytoskeleton of a cell?
microtubules and actin filaments
Your muscle cells need large amounts of ATP to function in the movement of your body. Which of the following organelles would you expect to be especially abundant in muscle cell?
mitochondria
The boundary that surrounds the contents of the nucleus is the
nuclear envelope
The region of the nucleus where ribosome production begins
nucleolus
Which of the following could not easily diffuse across a plasma membrane
sugar molecules
Lysosomes are organelles responsible for the breakdown of macromolecules. Why is it useful to have the lysosomal reactions compartmentalized rather than allowing them to take place freely in the cytoplasm of the cell
the absence of lysosomes would cause animal cells' vacuoles to burst
Which of the following works like a propeller
the prokaryotic flagella
The word fluid in the term fluid mosaic model refers to the fact that
the proteins within a membrane freely move around
Which of the following statements about hormones is false
they are not used by multicellular organisms
Channel proteins require energy for transporting molecules across the plasma membrane
true
Gap junctions allow large molecules to move from cell to cell
true
Ligand is another name for signaling molecules
true
The pH of a solution is 10. This means the solution is basic
true
microtubules are composed of tubulin monomers
true