Overtillage can increase the rate of humus decomposition
INCOMPLETE DOMINANCE INHERITANCE:
<span>5. In Andalusian fowl, B is the gene for black plumage (head feathers) and B' (pronounced "B prime") is the gene for white plumage. These genes, however, show incomplete dominance. The heterozygous (BB') condition results in blue plumage. List the genotypic and phenotypic ratios expected from the following crosses: a) black x blue b) blue x blue c) blue x white</span>
<span>6. </span><span>In snapdragons, petal color is determined by a single gene locus with two alleles making the "red" allele (R) incompletely dominant to the "white" allele (r). Heterozygotes have petals, which are neither red nor white, but pink. a) If a true-breeding red flower is pollinated with pollen from a white flower: What fraction of the seeds (F1 generation) would be expected to produce red-flowered plants? What fraction of the gametes produced by the F1 plants would be expected to bear the R allele? b) If two pink flowered plants are crossed, what genotypic and phenotypic ratios are expected among the offspring (F1 generation)?</span>
Answer:
The placenta is a unique vascular organ that receives blood supplies from both the maternal and the fetal systems and thus has two separate circulatory systems for blood: (1) the maternal-placental (uteroplacental) blood circulation, and (2) the fetal-placental (fetoplacental) blood circulation. The uteroplacental circulation starts with the maternal blood flow into the intervillous space through decidual spiral arteries. Exchange of oxygen and nutrients take place as the maternal blood flows around terminal villi in the intervillous space. The in-flowing maternal arterial blood pushes deoxygenated blood into the endometrial and then uterine veins back to the maternal circulation. The fetal-placental circulation allows the umbilical arteries
Explanation:
