Answer: Layer a is 500 million years old.
Explanation:
Trilobite is a member of the group of extinct arthropods found as fossils and they can be identified by the three-lobed as well as three segmented forms. These were the marine animals. These were appeared initially in the Cambrian Period. They used to live 542 million years ago so the fossils can be estimated to be aged of 500 above years old. These animals used to dominate in the sea area.
Answer:
The correct answer is - can be explained by the law of dominance.
Explanation:
In this experiment of Gregory John Mendel where he made a cross between a purebred tall plant and a purebred dwarf plant and in the first generation all the offspring were tall.
It can be explained by that every offspring get one allele from both parents and in purebred both alleles are either dominant or recessive and both parent plant gives one allele which makes a heterozygous condition in which the dominant allele masks the recessive allele and offspring express phenotype of the dominant parent.
Depending on baseline oxygen saturation and the pathological condition of the lungs, risks associated with altitude exposure include profound hypoxemia, pulmonary hypertension, disordered ventilatory control, impaired respiratory muscle function, and sleep‐disordered breathing.
Answer:
prokaryotes have no nucleus and membrane bound organelles but eukaryotes do
B. some substances must be dissolved in water before they can be used