Answers with solutions
This type of communication is long-lived and affects cells very distant from the releasing cell -
ANSWER Endocrine signaling
The molecules that convert extracellular signals into intracellular ones are - ANSWER Cell
surface receptors
Synaptic signaling requires - ANSWER nuerotransmitters
The critical checkpoints that control the cell cycle are at the - ANSWER G1 to S stage and G2 to
M stage
How does Viagra cause a similar effect to nitroglycerin - ANSWER Viagra causes an increase in
NO, which then acts to relax the blood vessels
In the digestive tract, adjacent cells develop connections to form a sheet that prevents leakage
of small molecules. These connections between cells are called - ANSWER tight junctions
All of the following statements about chemically-gated ion channels are true EXCEPT that -
ANSWER they close in response to binding of the signal molecule
The molecules that convert extracellular signs into intracellular ones are - ANSWER cell surface
receptors
The event that signals the start of anaphase is - ANSWER the division of the centromeres into
separate sister chromatids
, Which of the following is true regarding mitosis and binary fission? - ANSWER There is neither a
nucleus nor centromeres in prokaryotic cells that undergo binary fission
Steroid hormones are examples of signal tranduction using - ANSWER intracellular receptors
Angina is a pain caused by constricted blood vessels to the heart. How can the drug
nitroglycerin cause a change that will relieve this pain. - ANSWER The nitroglycerin is converted
by cells to NO, which then acts to relax the blood vessels
During cell division, plant cells differ from animal cells by - ANSWER forming a cell plate
In plants, cell-cell junction can only occur at gaps in the cell walls through cytoplasmic
connections that form across the plasma membranes of the touching cells. These junctions are
called - ANSWER plasmodesmata
The space into which neurotransmitters are released is called a chemical - ANSWER synapse
Plant and animal cells differ in cytokinesis in which of the following ways - ANSWER Vesicles
produce a cell plate in plant cells
How is Ras (a small G protein) able to act as a switch to link external signals to internal signal
transduction pathways? - ANSWER Ras is active when bound to GTP and inactive when bound to
GDP
Signal molecules activate intracellular receptors in - ANSWER target cells