6. The diagram shows the structures involved in a reflex action. hot pan
Which show the sequence in which these structures become involved?
(A) P→Q →R →S
(B) P→S → R→ Q
(C) Q → R→S→ P
(D) Q → S→ P→ R

the core of the sun is so hot and there is so much pressure, nuclear fusion takes place, hydrogen is changed to helium. nuclear fusion creates heat and photons. when the heat reaches the earth it warms the molecules of the atmosphere, and they warm other molecules and so on.

answer : haversian

[explanation: -(compact bone is organized as parallel columns, known as haversian systems, which run lengthwise down the axis of long bones. these columns are composed of lamellae, concentric rings of bone, surrounding a central channel, or haversian canal, that contains the nerves, blood vessels, and lymphatic system of the bone)]

a covalent bond, specfically triple bond