Answer: bone marrow
Explanation: Bone marrow is the soft, spongy tissue that is located in the medullary cavities (centers) of certain large bones. Healthy bone marrow is an essential part of the body, as it contains stem cells that produce blood cells and the cells that make up the immune system.
The answer is D! I hope that helps
Answer:
population density
population distribution
age structure
Explanation:
if we look at this question; it looks glaring that it correlates with a fill in the blank type of question.
So, from the question:
Frank counts 56 maple trees living on a 20-acre tract of land, and the data allows him to calculate the <u>population density</u> of the maple trees on the land.
In an ecological succession, population density refer to species of a common genera in specific geographical setting. It helps to measure the exact number of organism inhabitant a unit area of a place.
He observes that most of the maple trees grow closely together in groups of 6 to 8 trees, which describes the <u>population distribution. </u>
Population distribution is the spread of organism over a region in a geographic ecological setting. The pattern of distribution of organism may be uniform , in some organism they are largely dispersed and in some they are clumped together.
The<u> age structure </u>of the maple trees shows the percentages of trees of different ages.
The age structure is also a term used in ecology which is normally use to predict the proportion of growth of organisms. Age structure of species in the environment speaks volume about their distribution of age.
In this kind of population, the make up of the population's gene pool will remain virtually the same as long as these conditions hold. In this kind of situation, no evolution can take place, all thing will remain the same. For evolution to occur, competition must exist.
