Trisomy 21, as illustrated by the karyotype, is caused by nondisjunction. This occurs when chromosomes do not separate properly during meiosis.
Answer is D) nondisjunction
Answer:
A pea plant that has round seeds has the genotype Rr. It is crossed with a pea plant that ... Gregor Mendel used pea plants that were heterozygous for each of two traits- seed colour and seep shape- to generate a dihybrid cross. The phenotypic ratio of the resulting offspring was nine with round and yellow seeds,
Answer:
Ossification, or osteogenesis, is the process of bone formation by osteoblasts. ... The development of bone from fibrous membranes is called intramembranous ossification; development from hyaline cartilage is called endochondral ossification. Bone growth continues until approximately age 25.
Explanation:
The beginnings of a brain first become apparent around four weeks after conception when the neural plate folds to form the neural tube
