Answer:
Replicated chromosomes at metaphase I = 66
Sister chromatids at metaphase I = 66 x 2 = 132
Sister chromatids at prophase II = 66
Chromosomes in each sperm cells = 33
Explanation:
Metaphase I of meiosis I would have 66 replicated chromosomes in the testicular cells of the bird. Each of the replicated chromosomes would have two sister chromatids. So, a total of 66 replicated chromosomes would have 66 x 2 = 132 sister chromatids.
Due to segregation of homologous chromosomes towards opposite poles in anaphase I, each daughter cell formed by the end of meiosis I would have 33 replicated chromosomes. So, each of the daughter cells would have a total 33 x 2 = 66 sister chromatids at prophase II.
Since meiosis II maintains the chromosome number, each sperm cell formed by the end of meiosis II would have 33 chromosomes.
Answer:
Antibiotic resistance can evolved in bacterial population in the following ways:
Explanation:
- In response to constant exposure to antibiotics some members of a bacterial population develop some beneficial mutations in some essential genes that gives them survival advantage in terms of food and space over the sensitive bacterial strains and hence they are capable of out-competing the sensitive bacteria.
- This happens due to the process of Natural Selection.
- These genes are called antibiotic resistance genes and bacteria usually carry them on plasmids in form of cassettes where genes resistant to multiple drugs are incorporated. These plasmids are called the MDR or Multi-Drug Resistance Plasmids.
- These resistant plasmids can be easily transferred among bacterial populations by conjugation, transformation or transduction or direct plasmid transfer.
- The resistant genes encode for proteins that render the drug ineffective by promoting their efflux from the cells, preventing their entry into the cell, chemically modifying them such that they become non-functional or altering the target site of the drug.
Answer:
Air temperature
Explanation:
These variations in air pressure are due to temperature differences caused by variations in solar energy received at the surface of the earth
<span>d. neither of these will cross a plasma membrane.
Glucose cannot diffuse across a plasma membrane as it is polar. Since the question doesn't specify the type of diffusion, simple diffusion is assumed.
If you count facilitated diffusion, then A is the answer.</span>
The answer is A. Air
because our sound travel in the air so bat`s waves should travel in the air to find the insects that are flying in the air! :)))
i hope this is helpful
have a nice day
