Answer:
Neurotransmitters are endogenous chemicals that are released by axon terminals of neurons into the synaptic junctions and act locally to control nerve cell functions.
•Imbalance of neurotransmitters such as serotonin,norepinephrine and dopamine have been linked with depression.
•Abnormal levels of neurotransmitter glutamate leads to changes in the level of Dopamine which can cause transition into psychosis.Dopamine has been implicated as possible cause of schizophrenia.
•Several transmitters are involved in analgesia system (pain suppression),especially involved are enkephalin and serotonin. When Serotonin are released and this causes local cord neurons ti secrete enkephalin,which is believed to cause both presynaptic and postsynaptic inhibition of pain fibres.
•Parkinson's disease also known as paralysis agitans results from widespread destruction of that portion of substantia nigra that sends dopamine-secreting nerve fibres to caudate nucleus and putamen this leads to decrease in dopamine.
•Acetylcholine is responsible brain arousal and muscle contraction.
Answer:
C. Cnidarian tentacles have stinging cells, but Bryozoan tentacles are covered with cilia.
Explanation:
Cnidaria and Bryozoan, both teh phylum are classified under kingdom Animalia that contain aquatic animals found both in freshwater and marine environments.
They both use tentacles for feeding but there is diffference between there tentacles and feeding process.
Cnidarians tentacles are conist of stinging cells in the tips, which are called cnidocytes and a coiled thread-like stinger, called nematocyst. These stinging cells and nematocyst helps to capture and subdue prey. They feed over plankton or animals larger then them.
Bryozoan tentacles are covered with cilia and form an "O" or "U" shaped fold called lophophore, which helps to feed by sweeping the surrounding water. They generally feed on plankton, nudibranchs (sea slugs) and sea spiders.
Hence, the correct option is C.
Answer:
mutation rates can be used to design molecular clocks in order to estimate divergence times among species
Explanation:
In evolutionary biology, the substitution rates (also known as mutation rates) are used for the development of 'molecular clocks' which allow estimating the divergence times among species or among taxonomic groups. Molecular clocks can be designed by estimating the divergence rate of nucleotide sequences (either DNA or RNA) and amino acid (protein) sequences. These substitution rates can also be used to track how quickly viruses evolve (for example, in a pandemic situation).
Plants use energy from sunlight to turn water and carbon dioxide from what they get into an energy-rich sugar called glucose. This process is called photosynthesis, which means “making things with light”. In photosynthesis, the energy in light is absorbed by photopigments.
