Answer:
<h3>Biologists study humans, plants, animals, and the environments in which they live. They may conduct their studies--human medical research, plant research, animal research, environmental system research--at the cellular level or the ecosystem level or anywhere in between.</h3>
Answer:
Autotrophs are organisms that use light energy or energy stored in chemical compounds to make their own food.
1st order heterotrophs are organisms that eat only plants
2nd order heterotrophs are organisms that eat herbivores
3rd order heterotrophs: organisms that eat herbivores and other carnivores
Top group: carnivores
Explanation:
Producers are named as such because they produce their own food either by photosynthesis or chemosynthesis. These organisms are called autotrophs and include plants.
There are various levels of consumers. The first is first order heterotrophs, which feed on the producers. These are herbivores and include, for example, a deer feeding on grass.
The next is second order heterotrophs, which feed on the first order heterotrophs. E.g. an owl eating a mouse. These are carnivores
The next layer are also carnivores, third order heterotrophs which eat second order heterotrophs, for example a lion eating a zebra.
Answer:
b) At equilibrium, the species composition of an island will not change.
Explanation:
The Theory of Island Biogeography written by Robert H. MacArthur and Edward O. Wilson (1967) is an essential book for any professional working in biogeography, biodiversity, ecology, conservation and related fields. The theory of island biogeography states that species diversity on islands tends to approach a dynamic equilibrium due to the balance between colonization (inmigration), speciation and extinction. At equilibrium, the species composition of an island will change, precisely at the time that immigration and extinction processes maintain the number of species in a dynamic equilibrium, thereby maintaining species diversity. In this case, the colonization rate represents a function of distance to the continent (or other islands), the extinction rate is a function of the size of the island and habitat heterogeneity, and speciation is a function of time. This book also contains a series of useful considerations: 1-the number of species in an area is directly associated with the size of the area; 2-large islands support more diverse communities than small islands; 3-the viability of populations on island systems can be considered as a function of the island size and its proximity to the mainland (or other islands); and 4- when a habitat is lost the remaining fragmented area may lose some of its important species.
Genetic information from DNA to RNA is called transcription which involves the enzyme RNA polymerase. The DNA is read from 3' to 5' in direction and produces an mRNA (messenger RNA) which contains the genetic data from the DNA. This mRNA strand is further processed in the nucleus (capping and adding a poly-A tail) before being transported to the cytoplasm.
The information contained in mRNA is used to make a polypeptide chain is called translation. This involves the use of ribosomes in the cytoplasm which attach themselves to the mRNA strand then using tRNA (transfer RNA) to add amino acids to the elongating polypeptide depending on the codon in the mRNA.