Answer:
moving across both the plasma membrane and the outer membrane
Explanation:
Gram-negative bacteria are bacteria that have a plasma membrane, a thin peptidoglycan layer, and an outer membrane (the space between the plasma membrane and the outer membrane is known as periplasm). Moreover, Gram-positive bacteria exhibit neither outer membrane nor periplasmic space and are surrounded by thick layers of peptidoglycan. Gram-negative bacteria have developed different protein secretion systems (types I–VI and type VIII) in order to secrete proteins into the extracellular space. For such purpose, the XcpQ protein (which is an outer membrane protein from the secretin family) participates in different transport processes in Gram-negative bacteria.
Answer:
Capillaries connect the arteries to the veins. The arteries deliver oxygen rich blood to the capillaries, where the exchange for oxygen and carbon dioxide occurs.
Explanation:
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Answer:
A polygenic trait can be described as a physical trait which is influenced by more than one gene.
The three types of selection for a polygenic trait are:
1) Directional Selection: In a directional selection, one of the phenotype is favored in an ecosystem. As a result of this favoring, the allelic frequency changes and shifts in favor of this particular trait.
2) Stabilizing selection: It is a type of natural selection in which the intermediate trait is favored. The population carries a middle trait in abundance.
3) Disruptive Selection: Disruptive trait is a type of natural selection in which the traits on the extreme sides are favored. The intermediate traits are less favored.
Answer: Coral reefs are important to the ecosystem because they are the pillars on which marine and coastal ecosystems are built. They keep plants, fish, and animals fed. They clean up our water and protect our coasts.
Explanation: Hope it helps :)
Carbon dioxide can be transported through the blood via three methods. It is dissolved directly in the blood, bound to plasma proteins or hemoglobin, or converted into bicarbonate.
The majority of carbon dioxide is transported as part of the bicarbonate system. Carbon dioxide diffuses into red blood cells. Inside, carbonic anhydrase converts carbon dioxide into carbonic acid (H2CO3), which is subsequently hydrolyzed into bicarbonate (HCO3−) and H+. The H+ ion binds to hemoglobin in red blood cells, and bicarbonate is transported out of the red blood cells in exchange for a chloride ion. This is called the chloride shift.
Bicarbonate leaves the red blood cells and enters the blood plasma. In the lungs, bicarbonate is transported back into the red blood cells in exchange for chloride. The H+ dissociates from hemoglobin and combines with bicarbonate to form carbonic acid with the help of carbonic anhydrase, which further catalyzes the reaction to convert carbonic acid back into carbon dioxide and water. The carbon dioxide is then expelled from the lungs.
