Psychologist is interested in how early childhood nutrition affects height. To research this subject he tracks the nutritional consumption and growth of the same group of infants from age 1 through age 6. This research technique is utilizing a design

Longitudinal Design of research.

Explanation:

The psychologist is comparing the effects of nutrition on height and so he tracks the nutritional consumption and growth of same group of infants from age 1 to age 6. This means that he made repeated observation for the same variable in  same sample in order to trace the growth rate.

This design of research according to which a conclusion is derived after making repeated observation of same variable, is classified as Longitudinal design of research.

interphase

the period of cell growth when the cell synthesizes new molecules and organelles. the cell is not dividing and it constitutes the majority of the time spent in the cell cycle

prophase

changes occur in the nucleus and cytoplasm. the chromatin condenses to form structures (sister chromatids) visible with a light microscope and the mitotic spindle begins to form, but the nucleus is still in tact

prometaphase

the nuclear envelope fragments and the spindle microtubules attach to the kinetochores of the sister chromatids

metaphase

all the cell's duplicated chromosomes are lined up at an imaginary plane equidistant between the poles of the mitotic spindle

anaphase

begins when sister chromatids separate from each other and ending when a complete set of daughter chromosomes arrives at each of the two poles of the cell

telophase

the daughter nuclei form at the two poles of a cell

cytokinesis

the division of a cytoplasm to form two separate daughter cells. usually occurs during telophase during mitosis. this and mitosis make up to mitotic (m) phase of the cell cycle