Common parts of a cell
The cell is the building block of an organism, its smallest living unit. By definition, all cells have the following:
<span>A cell membrane: As a barrier between the cell and its environment, the membrane provides structure, protection and control over the movement of materials in and out of the cell.Cytoplasm: This refers to the contents of the cell membrane excepting the nucleus. One of its main components is cytosol, a jelly-like substance which acts as protection and support for the remaining contents.<span>DNA: Each cell contains genetic material. However, the way it is stored is one of the distinguishing factors between a eukaryote (a plant or animal cell for example) and a prokaryote (like a bacterium). These represent the two main types of cells. The former has a nucleus — for its DNA — as well as other organelles while the latter does not. Organelles are parts of a cell that have a specialised function and their own membranes.</span></span><span>Nucleus</span>
Answer:
Black
Explanation:
In the mouse a certain colorless pigment precursor exists.
- If the B allele is present: precursor is converted into black pigment.
- If the genotype is bb: albino
In addition:
- If the A allele is present: black pigment is converted to brown pigment
- If the genotype is aa: black pigment is not converted and mouse remains black
If the mouse has a genotype aaBB, the colorless pigment is converted to black (because there is at least one B allele) but the black pigment cannot be converted into brown (because there's no A allele), so the mouse will have black fur,
Nitrogen is fixed or combined, in nature as nitric oxide by lightning and ultraviolet rays, but more significant amounts of nitrogen are fixed as ammonia, nitrites, and nitrates by soil microorganisms.
The lymphatic trunk trains the lymph fluid into two lymph ducts: The thoracic lymph duct and the right lymphatic duct.
The thoracic lymph duct takes the lymph from the lower left halves of the body. It is the largest lymph vessel. It carries the lymph and chyle (emulsified fatty acids) back into the bloodstream. It drains lymph into the circulatory system via the left brachiocephalic vein.
The right lymphatic duct on the other hand gets lymph from the right and upper halves of the body. It drains lymph from the right upper limbs, right part of the thorax and the right half of the head and neck.
Answer: The correct answer is option C
Explanation:
Bombay phenotype refers to a rare genetic trait in which a person appears as blood group O even in presence of functional A, B, or AB alleles.
It is because of recessive mutation that occurs in other locus, that is, FUT1 gene. Normal gene produces H antigen or protein in the cell. This antigen is essential for the final expression of the ABO alleles.
If a person is homozygous recessive then he or she is not able to produce H antigen due to which the blood group appears as O.
However, if a person carries even a single functional copy of FUT1 gene, that is, heterozygous or homozygous then he or she can efficiently produce H antigen and then ABO alleles are expressed accordingly.
Thus, option C contains incorrect statement.
