C.
Every change in a species is coded within the DNA. But the bird had lost a toe an accident. So the toe-loosing-option isn't true because not every bird looses his toe.
(Example: If a women gets bitten by a snake on the arm and gets the arm removed from her body and then in a year or so has a baby with her new husband. The baby won't be born with one arm because his/her mother lost her arm.) <span />
Answer:
No to feel nervous is too feel the sense of feeling scared and has nothing to do with the nerves in your body
Answer:
Option (a) and (d).
Explanation:
The breaks in DNA molecule may occur due to replication error and oxidizing agent. The double-stranded breaks in DNA can be corrected by Homologous end joining and non homologous end joining.
Homologous end joining is used to repair the DNA present in G2 nad S phases of the cell cycle. The homologous sequences of DNA is used to repair the DNA. Non homologous end joining occurs in the cell present at G0 and G1 phase of the cell cycle. The DNA broken ends are juxtaposed and later rejoin together by DNA ligase.
Thus, the correct answer is option (a) and (d).
Answer:
Example of natural active immunity is fighting off cold and artifical active immunity is building up a resistance to a disease due to immunization and allergic reaction is an response to antigen resulting from active immunity
Answer:
Absorption
Thousands of pores on the surface of the skin can absorb vitamins, acids, water and oxygen in order to provide moisture and nourishment to our skin.
Excretion
The skin is the body’s largest waste removal system. Toxins are released through the sweat glands and pores.
Secretion
The skin secretes sebum, a mixture of oils that keeps the skin soft and supple. The layer of sebum on the outermost layer of the skin is known as the acid mantle. When intact the acid mantle has a PH that ranges from 4.5-5.5. The acid mantle is acidic in nature to protect the skin from outside invasion.
Regulation
The skin regulates the body’s temperature by sweating; when water from sweat on the skin evaporates it gives off heat and cools the body. The body’s temperature increases or by shivering or getting goosebumps when the body is cold. The contraction of muscles releases energy that warms the body.
Sensation
The skin contains millions of nerve endings that transport stimuli. These nerve endings allow humans to detect sensation such as heat, cold, pain and pressure.
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Sources: Salon fundamentals Esthetics Textbook: The Integumentary System