Out of the following given choices;
A. theory that fish and mammals have a common ancestry
B. theory that the first organisms on Earth were heterotrophs
C. close relationship between fish and mammalian reproductive patterns
D. close relationship between humans and annelids
The answer is A. Many embryos of the kingdom Animalia share similarities in the early stages depicting that they share a common ancestor. The gill slits is one example. They diverge in later stages to become Pharyngeal in the human embryo, while they differentiate into gills in fish.
Answer: Hydrogen bond or a covalent bond.
Explanation:
Answer:
Antheridia is the name of the male sex organs and archegonia is the name of female sex organs. Antherozoids are the male gametes, which are released by the antheridia.
Answer:
A. are caused by genes for defective proteins
Explanation:
Sickle cell anemia occurs when the gene coding for the beta chain of the hemoglobin has a substitution mutation. The mutant gene code for a faulty protein. The mutated hemoglobin forms aggregates and imparts sickle shape to the red blood cells carrying them. Similarly, hemophilia is caused due to mutation in the gene coding for Factor VIII. This protein is involved in blood clotting. The affected person has a deficiency of Factor VIII and experience severe blood loss even in case of a small injury.