Slow reproduction process is a disadvantage of sexual reproduction. So option A is correct.
Sexual reproduction is much slower than asexual form of reproduction and the meiosis process is much longer and complex than mitosis. The process of sexual reproduction depends on the fertilization and zygote formation which are time consuming processes. This longer duration of reproduction process leads to lesser number of individuals in the population. In this case there may be instances of producing only one organism per year and if by chance no offspring is produced for certain number of years can lead to extinction of the species.
Answer:
D. Type II alveolar cells
Explanation:
Three layers together make the diffusion membrane or respiratory membrane, which make the total thickness of less than a millimeter i.e. about 0.2 micrometer. The three layers are as follows:
1. The squamous epithelium of alveoli. There are two types of alveolar cells called type I and type II. Type I makes the exchange surface of alveolar membrane and type II cells are responsible for secreting the lung surfactant that reduces the surface tension.
2. Endothelial lining of blood capillaries. These is rich network of blood capillaries near the wall of alveoli.
3. In between the squamous epithelium and the endothelium of blood capillaries fused basement membrane is present.
Organism most likely to live the same time as Branchiopoda were trilobites
