How can a presynaptic neuron increase the intensity of the signal it is transmitting?
(a) increase the amount of neurotransmitters secreted
(b) change the type of neurotransmitter released
(c) increase the frequency of the action potential
(d) initiate a passive spread signal

The correct answer is option (a) "Increase the amount of neurotransmitters secreted".

Explanation:

Presynaptic neurons are helpful cells at chemical synapsis because they increase the intensity of the transmitted signals by increasing the amount of neurotransmitters secreted. The neurotransmitters are the carriers of information from the pre-synaptic—sending—neuron to the post-synaptic—receiving—cell, which results in an action potential.

answer: angiosperms

dicots

angiosperms are highly evolved plants, they produce seeds which are enclosed within in a carple. these are the largest group of plants on earth. they include trees, shrubs, herbs and small flowering plants. angiosperms exhibit a flowering stage in their life cycle. the flower serves the function of reproduction and fruit formation in majority of angiosperms. dicot is the term used to describe flowering plants that have two seed leaves. dicots are plants which develop seeds which split into two parts called cotyledons. each cotyledon contains one embryo.

here, a small purple flower development indicates that the plant belongs to angiosperms and having two embryonic leaves indicates it belongs to dicots.  

just finished the test, the answer is d, greg is the least cost-effective because he charges the most for the project