Because they are marine mammals and they need them to breathe out of
1) Ecology is the scientific study of the distribution and abundance of organisms, the interaction among organisms, and the interactions between organisms and their abiotic environment. Ecologists try to understand the inner workings of natural ecosystems and the species they contain.
2) Ecosystems have no particular size. An ecosystem can be as large as a desert or a lake or as small as a tree or a puddle. If you have a terrarium, that is an artificial ecosystem. The water, water temperature, plants, animals, air, light and soil all work together.
3) The biotic factors of an ecosystem include all the populations in a habitat, such as all the species of plants, animals, and fungi, as well as all the micro-organisms. Also recall that the nonliving factors are called abiotic factors. Abiotic factors include temperature, water, soil, and air.
4) For aquatic ecosystems, these factors include light levels, water flow rate, temperature, dissolved oxygen, acidity (pH), salinity and depth.
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Answer:
C. Organs are composed of tissues , which are composed of cells .
Answer:
C. A-T rich; initiator
Explanation:
Replication origins have A-T rich DNA sequences that attract initiator proteins.
Replication origin is the DNA sequence where replication is initiated in a genome. The replication origin sequences is rich in adenine (A) and thymine (T) bases because it is easier to break the bonds between the bases compared to the bonds between guanine and cytosine. adenine (A) and thymine (T) bases have two bonds joining them as against three bonds between guanine and cytosine
The initiator proteins recognizes DNA sequences in the replication origin and helps to initiate DNA replication.
Answer:
how meiosis affects chromosome number
