Answer:
every muscle cell of the motor unit is stimulated to contract.
Explanation:
Stimulus in biology can be defined as an obvious change in either the chemical or physical structure of an organism' environment (either external or internal). Thus, all living organisms (both animals and plants) respond to changes in their environment and consequently, an appropriate response or reaction is made. Also, stimulus arising from within the organism is known as internal stimulus while those from its environment are known as the external stimulus.
In organisms, the specialized cells that detect stimulus are generally known as sensory receptors while a group of these receptors is referred to as sense organ. Therefore, the senses are necessary for behavior because stimuli must be sensed in order to respond.
Stimulus control can be defined as a phenomenon that arises when a living organism responds or behaves in the presence of a stimulus and in another way in the absence of a stimulus.
For example, opening the door of a microwave oven as soon as its timer beeps.
Example II; When your body touches a hot object, you quickly move away and feel some pain subsequently.
Action potentials generates the nerve impulse in a motor neuron.
When an action potential is generated within a motor neuron, every muscle cell of the motor unit is stimulated to contract.
Answer: A recessive allele is only expressed if the individual has two copies and does not have the dominant allele of that gene.
Explanation: Recessive alleles are represented by a lower case letter, for example, a. The allele for blue eyes is recessive.
Answer:
they give the nutrients to the primary consumers.
Explanation:
producers are like-plants that are consumed by deer/bunnies etc. All those nutrients will decrease at the upper levels at the food chain so they have to have enough nutrients to keep the animals alive and healthy. When the lion eats the deer ( it was an example) some of the nutrients and minerals that the deer ate from the plant will be consumed by the lion while its being eaten.
<em>Hope this helps:)</em>
Answer:
C
Explanation:
When two species share a common niche, then one is bound to exclude the other. This is due to the stiff competition for resources. The species with a slight advantage in acquiring the resources will edge out the other species from the environment. This has been demonstrated by George Gauss using two Paramecium species grown in the same media in the lab. <em> P. aurelia</em> outcompetes <em>P. caudatum</em>
Answer:
In a particular case of secondary succession, three species of wild grass all invaded a field. By the second season, a single species dominated the field and the other two species had a lower relative abundance. A possible factor contributing to the abundances of these species in this example of secondary succession is <u>inhibition</u>.
Explanation:
Trees are great examples of allelopathy in plants. Some use their allelochemicals to inhibit germination or impede development of nearby plant life. Most allelopathic trees release these chemicals through their leaves, which are toxic once absorbed by other plants. Black walnut is a prime example of this.