When that situation happens then it can stimulate a cytotoxic T cell. This types of cells are the ones directly responsible for cellular immunity. Cytotoxic T cells can attack target cells by secreting a cytokine that triggers apoptosis which is <span>the death of cells which occurs as a normal and controlled part of an organism's growth or development.</span>
Mid ocean ridges occur where two tectonic plates diverge or move away from each other. This separation occurs under the ocean.The Mid-Atlantic Ridge is such an example and is where the North and South American plates pull away from the Eurasian and African plates. Mid ocean ridges are usually a combination of divergent and transform plate boundaries. At transform boundaries plates slide past each other in opposite directions.
The given blank can be filled with Cones.
The visual acuity can be defined as the clarity of the vision, it is related to the sharpness and the clearness of the image formed. The vision acuity is determined by the optical and the neural factors, it is dependent on the retinal focus and the sensitivity of the nerve cells and the brain.
The cones are the pointed, thick and short sensory receptors, present in the eye. They are responsible for the color vision and the sharpness or the acuity of the image. They work better in brighter light.
Correct answer: B). Shelter wood cutting takes place over several years
Shelterwood cutting is the progressively cutting of the forest, in order to establish the growth of the new generation of the seedlings of a particular species without planting.
It is a method of natural tree reproduction under the shelter of old trees, which are removed successively by cutting the tree in order to provide the increased amount of light to the new seedlings. It is a slow process and takes lot of time.
One disadvantage of having a large surface area to volume ratio is the heat loss. An organism that has larger surface area has high rate heat gain and heat loss. Therefore they need to eat or acquire nutrients faster in order to sustain life.