Answer:
Ecology is defined as the scientific study of the complex interactions between organisms, and the environment of the earth. Ecologists study, and examine the features of biotic and abiotic factors of the environment.
Abiotic factors include non-living factors, the physical, and chemical attributes, for example light, water, temperature, and nutrients which helps to influence the abundance, and distribution of organisms.
Biotic factors include living factors, the other organisms which are part of a separate environment, similarly influence the abundance and distribution of life present on Earth.
Yellow [YY] And Green [yy] would be [Yy] (Still yellow)
Answer:
Action potential in a motor neuron triggers the release of acetylcholine (ACh) neurotransmitter.
Explanation:
Acetylcholine: It is a neurotransmitter released by motor neurons which bind to the receptors end plates of the motor. When an action potential travel down the motor neuron's axon, neurotransmitter release occurs resulting in an influx of calcium and altered permeability of the synaptic terminal membrane.
The Ca2+ ions allow synaptic vesicles to move and bind with the presynaptic membrane which is present on the neuron and released neurotransmitter from the vesicles into the synaptic cleft. Once it's released ACh diffusion occurs across the synaptic cleft to the motor end plate, and binds with ACh receptor. As the neurotransmitter ACh binds, these ions channel open and sodium ions cross the membrane into the muscle cells.
In this phase reduction of voltage inside and outside the cell occurs, which is known as depolarization. When ACh binds to the motor end plate this depolarization is known as end plate potential. Then depolarization spread with the sarcolemma and creating an action potential. This action potential moves the entire cell and creating a wave of depolarization.
Answer:
A serial dilution and the following plating experiment is done in order to determine the actual amount of bacteria/microbes in a specific volume of soil sample. As a standard test, a set volume of the lower dilution is obtained and positioned on a median plate and permitted to increase for the needed amount of time. The amount of colonies is evaluated and thus the overall Colony Forming Units (CFU) is determined by unit volume of the sample plated and therefore the volume of soil sample employed.
Therefore,
The calculation is done using:
CFU/ml = Number of colonies appeared × dilution factor / volume plated
Given,
Number of colonies appeared = 97
dilution factor = 10^(-6)
volume plated = 1/10 = 0.1
This will help us calculate it as:
CFU/ml = 97 * 10^(-6) / 0.1
= 97 * 10^(-7) CFU/ml
This CFU/ml helps determine the amount of bacterial colonies per unit volume of sample plated.
Given,
The original sample as 1g or 1000 mg of soil in its total volume.
Therefore,
The number of bacteria can be calculated using:
Amount of bacteria in original sample
= 97 * 10^(-7) CFU/ml × 1/ 1000 mg
= 9.7 * 10^(-3) CFU/mg
Answer:
The correct answer is: Eccentric phase.
When talking about movement, we are talking about the activation of muscle fibers in order for this process to happen. In order for this to happen, motor neurons must activate the phases of muscle excitation, contraction and relaxation, so that the sarcomeres, and thus the fibers, can generate movement.
In essence, there are three stages, or phases, to complete muscle movement: the concentric phase, which is when the muscle fibers are excited and begin the process of contraction. This means the muscle fibers will contract and generate movement, generating a shortening. Then we have the isometric stage, a moment in which there is no longer any more shortening of the muscle fibers, so basically, the movement is held and there is no further contraction, but neither is there relaxation of the muscle fibers. Finally, we have the eccentric phase. This phase is characterized precisely because it is the moment when the muscles begin to return to their resting position.
