Answer:
Due to presence of these structures in ancient as well as modern organisms.
Explanation:
Homologous and vestigial structures are the evidences that show evolutionary relationships between organisms because these structure were also present in the ancient ancestor of that organism. These homologous and vestigial structures shows the relationship between the ancient and the modern organisms. Some structure has a purpose and function in the body of ancient organisms but with the passage of time those structure are useless and have no function in the body but these structure shows connection between modern and ancient organisms.
Answer:
A. The heartbeat can be heard
Explanation:
After the first trimester, during the fourth month, the heartbeat of the fetus becomes loud enough to be heard with the help of a stethoscope placed on the abdomen of the mother.
From fifth to the seventh month of the development, kicks and jabs are felt by the mother as the fetal legs grow and develops. Languo, a wrinkled pink colored skin covers the fetus.
Languo is in turn covered with a white greasy substance called vernix caseosa.
From eighth to ninth months, rotation of the fetus places its head pointing towards the cervix to facilitate childbirth later.
The development of testes takes place in the seventh month while the body hairs become disappeared in the eighth month.
It is called a Punnett Square
Answer:
D
Explanation:
Hormones are bigger than the cell pores hence cannot pass through the cell membrane to influence biochemical processes. Therefore, hormones (such as glucagon and insulin) bind onto receptors on the cell membrane, then transmembrane proteins, such as the G-protein, change conformation activating the secondary messengers inside of the cell. Cyclic- AMP is a major secondary messenger significant in activating protein kinases.
