The limb buds appears in the in the fourth week of gestation and the
upper limb is visible on day 24. Initial elongation of the bud forms around 33
days and continues to elongate until seven weeks.
The answer would be A - The animals gain nutrient-rich foods, and the angiosperms’ egg cells are fertilized.
{explanation: for it to be a mutualistic relationship both organisms would “work together”, each benefiting from the relationship; therefore, it’d be A.}
Answer:
Darwin's theory of natural selection lacked the physical proof of the intermittent species as suggested by him. The fossils of such species had not been discovered by the time he wrote his book 'Origin of species'. In order to defend his theory, he pointed out the non-reliability on fossils.
Explanation:
The field of geology was just evolving at the time Darwin wrote his book, and no fossils supporting his theory has been discovered yet. He defended his theory by saying that the fossils cannot be depended on for the proof of evolution as the the process of fossilization depends on many factors, and the available fossils are very rare. The irregularities in the geological records, also suggested that the fossil records are not perfect.
Defending his theory, he shows how, if available. the fossil records can support his theory. The fossils should show the features of both the extinct (parent species ) species and the present species, as the species present in today's world have evolved from the ones that existed long before them through the process of natural selection.
The discovery of the Archaeopteryx in 1861 supported his theory and the process of evolution as it showed the features of both the reptiles and birds.
The answer is B.
These elements are among the most important elements in life. Most of these elements are also non-metals. Elements life sulfur and nitrogen combine with carbohydrates to form among acids rings like cysteine. Carbohydrates combine with phosphorus to form molecules such as the DNA backbone chain.
The answer is B. 25°C.
A temperature of 25°C can be considered as a room temperature. It is an optimal temperature for the most living beings which cell potential is considered as standard. It is known that at 100°C water boils, so this temperature cannot be standard, cells will degrade at this temperature. Similarly 0°C and –273°C are too cold, water of the cells will freeze, cells will freeze, and cell potential will not be optimal.
