Answer:
3. An even number of chromosomes are required for synapsis during prophase I and proper pairing during metaphase
Explanation:
Mules are hybrids of a cross between a female horse and a male donkey. Horses contain 64 chromosomes while donkeys contain 63 chromosomes in their somatic cells respectively. This means that they each produce 32 and 31 chromosomes respectively during meiosis. A mule, hence, contains 32+31= 63 chromosomes in their somatic cells.
This chromosome number in mules are uneven for meiosis to occur because meiotic division requires that an even number of homologous chromosomes pair together in a process called SYNAPSIS during prophase I of meiosis I. This is impossible in a mule because of the uneven number of chromosomes in its cells.
Also, during metaphase of meiosis, the homologous chromosomes need to be properly aligned at the equator for separation to occur. This is also impossible in a mule considering the number of chromosomes that don't add up.
Due to this reason of unevenness in the number of chromosomes present in a mule, meiosis will not occur and if meiosis (gamete formation) does not occur, reproduction cannot take place. Therefore, the mule is a sterile species i.e. cannot produce offsprings via sexual reproduction.
Answer:
Electromagnatic waves.
Explanation:
The energy from the sun is transferred to the earth surface in the form of heat and light. This done through radiation and convection methods heat from the sun is transported to the earth surface through radiation and convection techniques while the light is being transferred.
Answer:
Thelarche
Explanation:
In females, thelarche represents the start of puberty and as such it marks the beginning of the secondary development of the mammary glands known as breasts. This pubertal development usually occur in females that are between the ages of 8 years and 12 years due to the secretion of hormones such as estrogen.
In this scenario, Emily's body starts to develop secretory glands at the end of the milk ducts in the breasts. Based on the given information, we can say that Emily is most likely to be in the thelarche stage because she is beginning to experience breast budding.
A group of subjects closely followed up together , also has mat variables
The answer should be Groundwater.
