Answer: B. secrete enzymes that kill bacteria
Explanation:
Paneth cells, so-called because they were first described by Dr. Josef Paneth in 1888, are pyramidal cells, with the nucleus in the basal position, and with large granules in the apical position. Its first isolated specific product was the lysozyme, a bactericidal substance, by Alexander Flemming. These cells play an important role in innate immunity in the small intestine, producing a wide diversity of antimicrobial peptides and enzymes such as lysozyme itself, cryptidines, defensins and a lectin with bactericidal properties.
Answer:
The human respiratory system contains the organs that allow us to get the oxygen we need and to remove the waste carbon dioxide we do not need. It contains these parts: two lungs. ... various structures in the chest that allow air to move in and out of the lungs.
Answer:
C) Through genomic imprinting, methylation regulates expression of the paternal copy of the gene in the brain.
Explanation:
The pattern of gene expression wherein either paternal or maternal gene is expressed in specific cells while the other one is prevented from expression is known as genomic imprinting.
In the given example, the maternal copy of the gene on chromosome 15 is expressed in brain cells while its paternal copy is not expressed in these cells. Hence, the pattern of expression of this gene is regulated through genome imprinting. One of the mechanism is methylation of cytidine residues of CpG islands of the DNA that are more frequently present within promoters of the genes.
When the cytidine residues of these sequences are methylated into 5-methylcytidine, the transcription factors do not bind to these promoters preventing the expression of these genes.
Hence, methylation of cytidine residue in CpG islands of the promoters of the gene present on chromosome 15 could have silenced its expression in brain cells.
Hello!
I believe the answer is the Gulf Coast toad.
Hope this helps! ☺♥
