Which of the following are plausible hypotheses that could explain why mammals never evolved unidirectional airflow through their lungs, while birds did? Select one or more: a. Mammals may have never experienced a need for unidirectional flow in their evolutionary past. b. The necessary alleles of developmental genes to develop associated structures of unidirectional flow never arose in mammals. c. Mammal-like lungs and bird-like lungs occupy different fitness optima in terms of having optimized capacity for gas exchange, and individuals of intermediate phenotype necessary to change to a bird-like lung would have to cross a valley in the fitness landscape. d. Unidirectional airflow would only benefit individuals but not the species overall. e. The necessary changes might need to happen at such an early developmental stage that altering the expression patterns of the genes involved might cause some additional severe developmental anomalies.
Answers: 1
Biology, 21.06.2019 19:30
Which type of organism is missing from the food web seen in the illustration? primary consumers decomposers primary producers secondary consumers
Answers: 2
Biology, 22.06.2019 01:00
Which of the following would be a body response when stepping outside without a coat on a snowy day? a. senaceous glands. secrete more senum b. more liquid is transported by the body to the skin fir insulation c. blood vessels in the skin narrow and contract d. blood vessels in the skin expand
Answers: 1
Biology, 22.06.2019 09:00
Which of these transport mechanisms moves glucose from the blood into a cell? active transport diffusion facilitated diffusion osmosis
Answers: 1
Which of the following are plausible hypotheses that could explain why mammals never evolved unidire...
English, 03.02.2021 01:00
History, 03.02.2021 01:00
Arts, 03.02.2021 01:00
Mathematics, 03.02.2021 01:00
Mathematics, 03.02.2021 01:00
Mathematics, 03.02.2021 01:00
Mathematics, 03.02.2021 01:00
History, 03.02.2021 01:00
Mathematics, 03.02.2021 01:00
Mathematics, 03.02.2021 01:00