Answer:
D.-
Explanation:
A control group is needed to carry out the experiment, that control group is the one that is not injected with anything. Ethanol and pesticide need to be injected into separated groups to document whether it is one or the other that is harmful
Answer:
1. Nerve impulse
2. Neurons
Explanation:
Neurotransmitters are compounds with low molecular weight. They are secreted by axon terminals of the neurons. The released neurotransmitters then bind to the receptors located on next neuron or on the surface of muscle cell.
The function of neurotransmitters is to carry the nerve impulse from presynaptic neuron to the postsynaptic neuron or from neurons to the effector organs such as muscles and glands.
For example, neurotransmitters are released into the synaptic cleft to transmit the nerve impulse between neurons.
Most of the marine animals have a stream lined body, which means, they have a sharp and pointed at the front. The pointed front of the organism allow to cut the resistance of the water. In case, the body is not pointed at the front and it is blunt, the water current and flow would resist the movement of the organism further. So, for the locomotion purpose, it is important to have a streamlined body. Further smooth and hair less body also decrease the resistance during the movement in the water.
The procedure by which the female gametes or ova are produced is known as oogenesis. The female gamete is known as an ovum. The process of oogenesis begins in the embryonic stage, the development of ovum takes place from the primary oocyte by maturation.
Each of the primary oocytes goes through the process of meiosis to generate one ovum. Thus, two primary oocytes will produce two ova after going through meiosis.
Protostomes develop a mouth first and then an anus. This is the difference between protostomes and deuterostomes.
In protostome development, there is a spiral radical and indeterminate cleavage. The blastopore becomes the mouth and the coelom forms from the mesoderm.
In deuterostomes development, radial and indeterminate cleavage takes place. The blastopore is the new anus and the coelom forms from budding off the wall of the archenteron.