Concept explainers
Insulin is a large, water-soluble hormone that binds to receptors on the outside surface of muscle, fat, and several other cell types. Insulin binding to its receptors activates proteins that in turn stimulate or inhibit many enzymes inside the cell. One of the activated enzymes starts a cascade of reactions inside the cell, with the result that glucose-transporting proteins are moved to the plasma membrane. Once in the plasma membrane, the transport proteins facilitate the diffusion of glucose into the cell.
Insulin is essential to regulate
Want to see the full answer?
Check out a sample textbook solutionChapter 38 Solutions
Biology: Life on Earth with Physiology (11th Edition)
- What would happen in each of the following cases where something related to intracellular transport is altered? Assume in each case that the protein involved is a soluble protein, not a membrane protein. State where each protein would be located and explain each of your answers. You add a signal sequence (for the Golgi) to the N-terminal end of a normally cytosolic protein. You change the hydrophobic amino acids in an ER signal sequence into other, hydrophobic, amino acids.arrow_forwardEukaryotic membrane fluidity can be increased by which of the following mechanisms? increasing the number of fatty acids attached to glycerol in membrane lipids decreasing the number of branched chain fatty acids of membrane lipids decreasing the number of carbons in the fatty acids of membrane lipids decreasing the number of membraned organelles in the eukaryotic cell increasing the degree of saturation in the fatty acids of membrane lipidsarrow_forwardCO2 can cross the plasma membrane by diffusion. If a cell is in the process of metabolizing glucose, which direction would diffusion tend to carry CO2 molecules? (It may help to consider: where is CO2 highly concentrated? Would diffusion carry CO2 toward or away from this location? Group of answer choices A. From inside the cell to outside the cell B. From outside the cell to inside the cell C. not enough info to tellarrow_forward
- Which of the following molecules would be able to passively diffuse into or out of the cell? Glucose, a sugar Insulin, a protein Oxygen gas Sodium ionarrow_forwardEukaryotic membrane fluidity can be decreased by which of the following mechanisms? decreasing the number of fatty acids attached to glycerol in membrane lipids increasing the number of carbons in the fatty acids of membrane lipids increasing the degree of unsaturation in the fatty acids of membrane lipids decreasing the number of membraned organelles in the eukaryotic cell increasing the number of branched-chain fatty acids of membrane lipidsarrow_forwardMatch the transport process to the correct description or example. Primary Active Transport is: Group of answer choices transport of glucose out of cell, with its concentration gradient transport of sodium out of a neuron using the sodium potassium pump breaking of a covalent bond to create new molecules transport of large macromolecules into a cell transport of signal molecules out of an endocrine cell transport of a steroid hormone into a cell transport of glucose into a cell, against its concentration gradient import of an entire bacterium into a white blood cellarrow_forward
- Glucose enters the cell through a protein called a glucose transporter. It is an example of facilitated diffusion. Which of the following is false? The glucose flows with its gradient. The interior of the transporter has non polar residues. There are many types of glucose transporters. Energy is not required.arrow_forwardOne protein made by these cells is (myelin, actin, myosin) that is essential in neurological function as seen in ( multiple sclerosis, epilepsy, brain tumors) where the degeneration of the protein is observed and patients experience neurological symptoms.arrow_forwardWhich of the following regulatory methods could never increase enzyme activity? phosphate removal by a phosphatase phosphate addition by a kinase allosteric regulation negative feedback positive feedbackarrow_forward
- Ca2+-ATPases are integral membrane proteins. They are active transport mechanisms that use the energy derived from ATP hydrolysis to pump calcium ions across the membrane. A specific form of Ca2+-ATPase, ERCA, is located on the endoplasmic reticulum membrane. In which direction does ERCA transport calcium ions? a.) ERCA transports calcium ions from the lumen of the endoplasmic reticulum into the cytoplasm. b.) ERCA transports calcium ions from the cytoplasm into the lumen of the endoplasmic reticulum.arrow_forwardWhen the proteins of human gut epithelial cells adhere to each other so tightly that digestive enzymes from the intestinal lumen cannot pass between the cells, these proteins are exhibiting: unrestricted movement, similar to membrane phospholipids (like phosphatidylcholine) restricted movement, based on confinement by diffusion barriers (like tight junctions) restricted movement, based on tethering to extracellular molecules (like collagen) restricted movement, based on attachment to other cells (by proteins like keratin) restricted movement, based on anchoring to intracellular proteins (like spectrin)arrow_forwardSay that a heart muscle cell has low levels of ATP and high levels of ADP, what kind of problems is the cell likely to have? Group of answer choices a. It will not be able to use energy that is extracted from glucose to contract b. It will have too much energy and contract uncontrollably c. It will not be able to build new molecules like enzymes and transporters d. It can use glucose for energy but not fatty acids e. This will not greatly affect the function of the cellarrow_forward
- Human Physiology: From Cells to Systems (MindTap ...BiologyISBN:9781285866932Author:Lauralee SherwoodPublisher:Cengage Learning