Answer:
a. Mammalia
Explanation:
Mammalia are the class species that have distinct systems and separate ducts for different activities like reproduction, excretory, and defecatory and moreover they have nipples to feed their young ones.
So, the above species which has a single duct for reproductive, excretory, and defecatory material as well as a lack of true nipples does not belong to Mammalia
Human reproduction<span> takes place as internal fertilisation by sexual intercourse. During this </span>process<span>, the male inserts his penis, which needs to be erect, into the female's vagina, and then either partner initiates rhythmic pelvic thrusts until the male ejaculates semen, which contains sperm, into the vaginal canal.</span>
The correct answer is choice B, Tt. I hope this helps.
Answer:
CO2 increases the affinity of oxygen for hemoglobin so that hemoglobin binds oxygen more strongly
Explanation:
Hemoglobin (Hb) is a protein found in red blood cells that functions to transport oxygen (O2) to the tissues. This protein has four subunits and each subunit binds to a heme group. Each heme group in Hb contains an iron atom that binds to one O2 molecule. The affinity of hemoglobin for O2 is a critical mechanism that is dependent on the ability of Hb to carry O2 molecules. Hb is fully saturated with O2 when all of its four O2-binding sites are occupied. Moreoever, the O2-hemoglobin dissociation curve is a plot of saturation of Hb regarding the partial pressure of O2 (PO2). A rightward shift in the curve indicates that Hb has a decreased affinity for O2, while a leftward shift in the curve indicates that Hb has an increased affinity for O2. As CO2 concentration increases, hemoglobin's affinity for O2 decreases, thereby Hb binds to O2 less tightly at heme group sites and therefore the dissociation curve shifts to the right.
