Answer:
By performing a test cross i.e. a cross with a recessive trait
Explanation:
According to the question, hairlessness is a recessive trait, meaning that it will only be expressed in a homozygous condition i.e. when there are two recessive alleles in the genotype. Presence of hair is dominant, meaning that it will mask the phenotypic expression of hairlessness allele in a heterozygous state. Hence, a dominant phenotype can either be homozygous (same dominant allele) or heterozygous (combination of dominant and recessive alleles).
In order to determine which of these genotypes the dominant phenotype possess, we perform a test cross. A test cross is a cross performed to determine the genotype of the dominant organism by crossing it with a homozygous recessive genotype.
Ideally, the offsprings resulting from the cross will all be phenotypically dominant if the organism in question is homozygous dominant but if the organism is heterozygous dominant, the offsprings will occur in an equal ratio of dominant to recessive phenotypes.
So in this case, all of offsprings of this cross between the rat terriers will possess hair if the dominant rat terrier dog is homozygous, but if the dominant rat terrier dog is heterozygous, an hairless offspring will be produced.
Answer:
Mammalian dentition is characterized by heterodonty, in which both the upper and lower teeth are differentiated morphologically into four types: flat, chisel-shaped incisors, conical canines, bicuspid premolars and multicuspid molars in the mesiodistal direction.
Explanation:.
- <u>The mesiodistal crown:</u>dimension is the smallest of any maxillary teeth.The mesiodistal measurement of the pulp chamber is wider compared to the labiopalatal one. The periphery of the socket often dips down palatally, labially, mesially and distally to accommodate the shape of the root.
- <u>Maxillary central incisor:</u>The general shape is similar to maxillary central incisor except that they are shorter and narrower. It has the most cervically located contact area of any incisor. The mesioincisal and distoincisal angles are more rounded than the corresponding angles of maxillary central incisor.
- <u>Permanent mandibular central incisor:</u>The crown dimensions are the smallest of any tooth, it has bilaterally symmetrical crown, and the line angles are the sharpest of any tooth.It shows the shallowest labial developmental grooves, smoothest lingual surface contour and the least developed cingulum.
<span>Streptococcus is a genus of coccus (spherical) Gram-positive bacteria belonging to the phylum Firmicutes[3] and the order Lactobacillales (lactic acid bacteria). Cell division in this genus occurs along a single axis in these bacteria, thus they grow in chains or pairs, hence the name—from Greekstreptos, meaning easily bent or twisted, like a chain (twisted chain). Contrast this with staphylococci, which divide along multiple axes and generate grape-like clusters of cells.)</span>