Scientists believe that at first these bears scavenged seal carcasses that had washed ashore, and gradually began to hunt the seals by waiting at the water's edge as the seals surfaced to breathe. This is believed to be an important step in the evolution of a new bear species, the polar bear
Over time the new polar bears were used to the cold climate and learnt how to fish, they then separated from the grizzly bears, they developed new creatures which would help them survive in one of the most dangerous climate.
Answer:
sympathetic stimulation
Explanation:
Under stress or emergency conditions, the preganglionic neurons of the sympathetic division release acetylcholine. Acetylcholine stimulates secretion and release of epinephrine and norepinephrine from the adrenal medulla. These hormones enhance the effects of the sympathetic division of the autonomic nervous system (ANS) during stress. Epinephrine and norepinephrine augment the fight-or-flight response as they increase the heart rate and force of contraction, the output of the heart, and blood pressure. They also increase blood supply to the heart, liver, and adipose tissue. The airways to lungs become dilated and there are increase blood levels of glucose and fatty acids.
At the centre is a sugar molecule, ribose (the same sugar that forms the basis of RNA). Attached to one side of this is a base (a group consisting of linked rings of carbon and nitrogen atoms); in this case the base is adenine. The other side of the sugar is attached to a string of phosphate groups. These phosphates are the key to the activity of ATP.
<h2><u>Let's start with a quick review!</u></h2><h3 /><h3><u><em>What is a prokaryotic cell?</em></u><em> Well, a prokaryotic cell is a type of cell that does not have a true nucleus or membrane-bound organelles. Organisms within the domains Bacteria and Archaea are based on the prokaryotic cell, while all other forms of life are eukaryotic. (G o o g l e gave me this.)</em></h3><h3><u><em>What is a eukaryotic cell? </em></u><em> Well, eukaryotic cells have a nucleus enclosed within the nuclear membrane and form large and complex organisms. Protozoa, fungi, plants, and animals all have eukaryotic cells. They are classified under the kingdom Eukaryota.</em></h3><h2><u><em>Now, I will answer your question.</em></u></h2><h3 /><h3><em>Cell membrane, Eukaryotic.</em></h3><h3><em>Nucleus, Eukaryotic.</em></h3><h3><em>Mitochondria, Eukaryotic.</em></h3><h3><em>Ribosomes, Both.</em></h3><h3><em>Endoplasmic reticulum, Eukaryotic.</em></h3><h3><em>Cytoplasm, Both.</em></h3><h3><em>Vacuole, Both.</em></h3><h3><em>Chloroplast, Eukaryotic.</em></h3>
<u>(Note, you may have to look the last one up)</u>
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