Differentiate between density-dependent and density-independent factors affecting population growth. Provide two
examples for each, along with a brief explanation. What will be an ideal response?
Concepts to Consider: Density-dependent factors are those whose influence on the growth
of a population reflects the population density. As the population density increases, the
impact of these factors increases and contributes to a slowing of the growth rate through an
increase in the death rate or a decrease in the birth rate. The converse is also true. Examples
of density-dependent factors include predation, disease, and competition. Densityindependent
factors tend to be abiotic, are not influenced by population density, and may
have unpredictable effects on the population. Examples of density-independent factors
include unusual weather events such as early freezes, floods, fires, and hurricanes.
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When you look at a phylogenetic tree of reptile classes, turtles, lizards and snake, and crocodiles are grouped together and birds are set off to the side but with a common ancestor for both groups. This would
A. be a monophyletic tree. B. be a paraphyletic tree. C. be a polyphyletic tree. D. have the taxonomy wrong because birds should be included with the others to make it a monophyletic tree. E. be a paraphyletic tree but the taxonomy wrong, because birds should be included with the others to make it a monophyletic tree.
Red blood cells originate from the bone marrow.
a. true b. false
________ is a polymer of glucose.
A. Triglyceride B. Cellulose C. DNA D. Protein E. RNA