The randomness in the alignment of recombined chromosomes at the metaphase plate, coupled with the crossing over events between nonsister chromatids, are responsible for much of the genetic variation in the offspring. To clarify this further, remember that the homologous chromosomes of a sexually reproducing organism are originally inherited as two separate sets, one from each parent. Using humans as an example, one set of 23 chromosomes is present in the egg donated by the mother. The father provides the other set of 23 chromosomes in the sperm that fertilizes the egg. Every cell of the multicellular offspring has copies of the original two sets of homologous chromosomes. In prophase I of meiosis, the homologous chromosomes form the tetrads. In metaphase I, these pairs line up at the midway point between the two poles of the cell to form the metaphase plate. Because there is an equal chance that a microtubule fiber will encounter a maternally or paternally inherited chromosome, the arrangement of the tetrads at the metaphase plate is random. Thus, any maternally inherited chromosome may face either pole. Likewise, any paternally inherited chromosome may also face either pole. The orientation of each tetrad is independent of the orientation of the other 22 tetrads.
Explanation:
High pressure. Clouds form due to air rising so if the pressure is high, it pushes down on the air which prevents cloud formation.
Answer:
1. Circulatory System
2. Respiratory System
3. Endocrine System
4. Nervous System
5. Urinary/ Excretory System
Explanation:
1. Circulatory System- The heart pumps blood and blood vessels such as arteries and veins, transports the blood to every part of our body providing organs and muscles with nourishment.
2. Respiratory System- This system maintains our breathing. It supplies the body with oxygen for cellular respiration.
3. Endocrine System- The glands of the endocrine system secrete chemicals called hormones that regulate most of the processes in our bodies like growth, reproduction, metabolism, etc...
4. Nervous System- The entire nervous system controls all of the other systems of the body and it also transmits information to the brain, such as pain and external sensations.
5. Urinary/Excretory System- This system is responsible for eliminating waste products of metabolism and other materials from the body that are of no use.
Answer:
The frequency of individuals with the dominant phenotype is 0.83.
Explanation:
We are provided with:
Black allele has completed dominance over brown allele
T. no of dogs (dominant)= 2000
No. of black dogs (dominant) = 1660
From Hardy-weinberg equilibrium
Frequency of individual - (individual/ Total population)
Frequency of black dogs = 1660/2000 =
0.83
So, The frequency of individuals with the dominant phenotype is 0.83
By spreading the seeds of other plants with others, effectivly creating the first pesticides
LOL Hope this helps!<span />
