Answer:
E. a, b and c
Explanation:
Gas exchange near tissues: Near the tissues the partial pressure of oxygen is less so oxyhemoglobin in the blood immediately dissociates to give away oxygen to the tissues.
Near the tissues the metabolized product carbon dioxide is more i.e. the partial pressure of carbon dioxide is more near tissues. A rise in partial pressure of CO2 of fall in pH, decreases oxygen affinity of hemoglobin, this is referred as Bohr's effect. Hemoglobin undergoes conformational changes that facilitates the release of oxygen.
Carbon dioxide must be transported from tissue to lungs for exhalation process. For this some part of CO2 (20-25%) binds with hemoglobin and gets transported as carbaminohemoglobin (HbCO2). Around 70% of CO2 is transported in the form of bicarbonate ions and the remaining 7% in the dissolved form in plasma.
<u>Answer</u>:
Option 1.Eukaryotic cells first seen
Option 5. oxygen builds up in the atmosphere
<u>Explanation</u> :
- The name <em>Proterozoic eon</em> is derived from a Greek word which means earlier life.
- This eon represents the time just before complex life started proliferating on earth.
- One of the most important events that took place during this eon was <em>build up of oxygen in the atmosphere</em>.
The fossil evidence also shows the occurrence of <em>advanced single-celled eukaryotes.</em>
<em>So the events that define the Proterozoic eon are eukaryotic cells first seen and oxygen build up in the atmosphere. </em>
Answer:
The correct answer is option second - methionine.
Explanation:
During translation, the initiator tRNA binds with a smaller subunit of the ribosome and this assembly bind to the start codon AUG at mRNA molecule in both prokaryotes and eukaryotes and then large subunit bind to this assembly and start polypeptide chain.
So, the first codon is AUG which is start codon and code for methionine in eukaryotes and fMeth in prokaryotes at newly translated prokaryotic and eukaryotic polypeptides at the N- terminus.
Thus, the correct answer is option second - methionine.
Phillis Wheatley compares the human heart to the setting sun.
