This pedigree shows the inheritance of a recessive trait in humans. Individuals that have the trait are homozygous for a recessive allele a. If H and I, who happen to be first cousins, marry and have a child, what is the chance that this child will have the recessive trait?

#Question id: 11081

#Unit 7. System Physiology – Animal

In which of the following conditions is alveolar Po2 increased and alveolar Pco2 decreased?

#Question id: 3609

#Unit 8. Inheritance Biology

In humans, the dominance relationship between the A and B alleles of the ABO blood group gene is an example of

#Question id: 12742

#Unit 13. Methods in Biology

#Question id: 529

#Unit 1. Molecules and their Interaction Relevant to Biology

When a muscle is stimulated to contract aerobically, less lactic acid is formed than when it contracts anaerobically because:

#Question id: 4973

#Unit 11. Evolution and Behavior

Fossils of Lystrosaurus, a dicynodont therapsid, are most common in parts of modern-day South America, South Africa, Madagascar, India, South Australia, and Antarctica. It apparently lived in arid regions, and was mostly herbivorous. It originated during the mid-Permian period, survived the Permian extinction, and dwindled by the late Triassic, though there is evidence of a relict population in Australia during the Cretaceous. The dicynodonts had two large tusks, extending down from their upper jaws; the tusks were not used for food gathering, and in some species were limited to males. Food was gathered using an otherwise toothless beak. Judging from the fossil record, these pig-sized organisms were the most common mammal-like reptiles of the Permian.Which of Lystrosaurusʹ features help explain why these organisms fossilized so abundantly?

I. the presence of hard parts, such as tusks

II. its herbivorous diet

III. its persistence across at least two geological eras

IV. its widespread geographic distribution

V. its mixture of reptilian and mammalian features