Answer:
More than 7000 chemicals are present in tobacco smoke.
Explanation:
In these 7000 chemicals, 250 are harmful to the human body such as carbonmonoxide, ammonia and hydrogen cyanide etc. There are some chemicals that are found in tobacco smoke which causes cancer disease in human. About 69 chemicals out of 250 are present in tobacco smoke that causes cancer disease. So its consumption is dangerous for health.
D.8 should be the correct answer
Answer:
Epidermal cells secrete the waxy hydrophobic substance cutin that polymerizes on the surface, forming a barrier to water evaporation. Epidermal cells are transparent because their plastids remain small and undifferentiated; hence light readily penetrates through to the photosynthetic tissues beneath the epidermis.
Explanation:
Answer:
Answered below
Explanation:
On piercing his foot, the pain receptors called nociceptors, found in the skin, are activated. Nociceptors exist at the nerve endings of the primary afferent neurons. Signals travel along the first order neurons which have cell bodies within the dorsal root ganglia of the spinal cord. In the dorsal root ganglia, the signals are taken up at the synapse with the second order neurons which have cell bodies in the nuclei of the cranial nerves within the brainstem. These neurons ascend cranially in the spinothalamic tract to the thalamus. The third order neurons lie within the ventral posterolateral nucleus of the thalamus. They terminate at the somatosensory cortex where the signals are being processed and returned as a sensation of pain.
1. The study of all life or living matter.
2. The living organisms of a particular region.
3. The structure, function, and behavior of an organism or type of organism.
