The mechanisms of reproductive isolation prevent the reproduction of two individuals from different species. The prezygotic mechanisms disrupt the stages of reproduction before the forming of the zygote or prevent the mating at the start, and the postzygotic mechanisms affect the stages of reproduction after the forming of the zygote.
So, the first and the third example (the urchins and the grasshoppers) show the prezygotic mechanism, as the two individuals are not able to mate or form a zygote.
The second and the fourth example ( zonkey and the death of a zygote) show the working of the postzygotic mechanisms, as the zygote is formed, but it seems to be inviable, and the zonkeys are sterile, preventing the individual to reproduce.
Answer:
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Explanation:
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Answer:
<u>Pro:</u>
May hold answers to cure various diseases including Alzheimer's and Parkinson's - these may be answers to various diseases that are not able to cure.
Requires a small number of cells because of the fast replication rate - these are able to produce a high amount of cells in the lab as they are able to replicate faster.
Medical benefits such as regenerating organ tissue and therapeutic cell cloning
<u>cons:</u>
ethical controversy over use of stem cells from lab fertilized human egg - there is an ethical controversy around the use of lab fertilized human egg
unproven treatments often come with high rejection rates - these researches provide uncertain results and not tested and easily affected so the rate of rejection is high
The cost can be prohibited for many patients - these require high cost and can not be in the budget of every patient.
Answer:
C. Primary, secondary, and tertiary structures would be altered
Explanation:
Frameshift mutations refer to the mutations that change the reading frame of the gene. Frameshift mutations are mostly caused by insertion or deletion of nucleotide since addition or loss of nucleotide alters all the codons present downstream of the point of the mutation site. If frameshift mutation occurs at the beginning of the protein sequence, all the downstream amino acids would be altered.
The changed amino acid sequence would alter the primary structure of the protein. Since the secondary and tertiary structure of proteins is determined by interactions between the R groups of amino acids, their polarity, charge, etc., the altered amino acid sequence would also alter secondary, and tertiary of the protein.
Is the matter we take in when we eat only used for cellular respiration?
Answer: Food is your body's only supply of energy. However, this energy must be converted from the apple (or any other food you eat) into an energy source that your body can use. The process of getting energy from your food is called cellular respiration.
