Answer:
There are different evidences for evolution that includes anatomy, fossils, molecular biology and biogeography.
Molecular biology uses DNA and protein sequences that the genetic code reflect the shared ancestry of life. DNA comparisons used for the anatomical evidence.
All living cells are organized in the same basic DNA and use the same genetic code. Proteins derived from genes, all originate from the same set of amino acids. Comparing parts of DNA in various species has shown that even very different organisms still have significant parts of similar DNA. For example, in chimpanzees and humans have some precent of same genetic structure. In the amino chain, chimpanzees and humans have only one position, while humans and moths have 31 different positions.
<u>There are different advantages and disadvatages of each type of evidences are:</u>
Advantages:
- Anatomy share information about the similar physical structures shared by common ancestor (homologous structures)
- Fossils provide information about the extinct species.
- Molecular biology provide genetical relationship between organisms.
- Biogeography share global organism distribution and island species unique characteristics reflect evolution and geologic change.
Disadvantages:
- some of the structures such as forelimbs of human and birds seems homologous in structure as per comparative anatomy but they have evolved independently in each species.
- Fossils are impressions of past living organism and buried in earth surface rom long geological past, hence during this geological time there can be many changes in the fossil structure and can manipulate the evidences.
- Molecular biology has disadvantage of lack of assay specificity and sensitivity.
- organism can evolve and adapt according to different condition, hence Biogeography can not exactly tell the exact changes in the characteristics of organisms on the basis of particular geology.
I think it’s will be A but not sure
Answer:
- Pesticide 1: Induces transition mutations. Rat liver enzymes convert it into a nonmutagenic product. Does not induce frameshift mutations.
- Pesticide 2: Does not induce transition mutations. Rat liver enzymes convert it into frameshift mutagen.
- Pesticide 3: Induces transition mutations. Rat liver enzymes don't have ability to convert compounds into mutagens. Does not induce frameshift mutations.
Explanation:
The Ames test is a technique widely used to evaluate the mutagenic potential of a particular chemical compound. The Ames test uses <em>Salmonella typhimurium</em> strains with a defective mutation that makes them unable to synthesize histidine. When the mutation is reversed, then the revertant strains can grow on a medium lacking histidine. A positive test shows that the chemical is mutagenic because its activity is associated with the reversed mutation and thereby the mutant gene regains its function. In humans, as well as in other mammals, many chemicals don't have mutagenic effects themselves but they may become converted into mutagens when are metabolized by the body. For that reason, rat liver enzymes are added to replicate the metabolic effects of the chemical compound being tested. Nowadays, current tests can express recombinant human proteins instead of rat liver enzymes, thereby enabling a better correlation between mutagenic activity and human metabolic processes.
Answer:
a) It must occur before a cell can divide
Explanation:
A
Explanation:
Cellulose is insoluble most animals can't digest