The type of chemical that attracts males, even from a distance is called a pheromone, and these chemicals are used by a variety of animals.
ribosomes, cytoplasm, and cell membrane
Answer:
All of the statements are true.
The X chromosome is one of the two sex chromosomes of humans and some animals (the other sex chromosome is the Y chromosome). Men have a single X chromosome and women two X chromosomes.
Diseases whose gene is localized on the X chromosome are most often transmitted in the X-linked recessive mode; some are transmitted on the dominant mode related to the X.
In this mode of inheritance, the morbid allele behaves like a recessive trait.
Women heterozygotes are not affected but can transmit the disease; they are aid to be conductive of the disease.
The disese is only manifested in male subjects (XY) with only one copy of the gene (hemizygous subjects)
Answer:
4: epistasis
Explanation:
<em>Epistasis is a form of gene interaction in which a gene on one locus modifies or suppresses the effects of another gene on a separate locus. </em>
Epistatic gene interaction can be dominant, recessive, duplicate recessive, duplicate dominant, or polymeric gene interaction.
- Recessive epistasis occur when a recessive allele at one locus suppresses the expression of alleles on separate locus/loci.
- Dominant epistasis occur when a dominant allele at one locus suppresses the expression of alleles on separate locus/loci.
- Duplicate recessive epistasis occur when recessive alleles at either of two loci suppress the expression of dominant alleles at the two loci.
- Duplicate dominant epistasis occur when dominant alleles t either of two loci suppress the expression of dominant alleles at the two loci.
- Polymeric gene interaction occur when two dominant alleles which have similar effect individually produce enhanced effect when they come together.
<em>In this case, the expression of gene is controlled by the presence/absence of gene N on a separate locus. In homozygous recessive form, gene N suppresses the expression of gene S, a clear case of recessive epistasis.</em>
The correct option is option 4.