Answer:
During Anaphase stage
Explanation:
Meiosis is the type of cell division employed during gamete formation when each resulting gamete (daughter cell) has their chromosomal number reduced by half. Meiosis occurs in a two step division; Meiosis I and II. Meiosis I involves the separation of homologous chromosomes (similar but non-identical chromosomes received from each parent) while Meiosis II involves separation of sister chromatids (replicated chromosomes).
Alleles are present on the chromosomes which segregate or separate during the anaphase stage. Alleles received from each parent are separated in Anaphase I of meiosis I, which the identical replicated alleles are separated in anaphase of meiosis II.
<h2>Down Syndrome</h2>
Explanation:
Down syndrome is a genetic disorder caused when abnormal cell division results in an extra full or partial copy of chromosome 21
- Down syndrome is a genetic disorder caused when abnormal cell division results in an extra full or partial copy of chromosome 21
- Down syndrome is usually caused by an error in cell division called nondisjunction which results in an embryo with three copies of chromosome 21 instead of the usual two
- Prior to or at conception, a pair of 21st chromosomes in either the sperm or the egg fails to separates
- With development in embryo the extra chromosome is replicated in every cell of the body;this type of Down syndrome which accounts for 95% of cases is called trisomy 21
- Maternal age is the only factor that has been linked to an increased chance of having a baby with Down syndrome resulting from nondisjunction;here environmental agents such as drugs, chemicals, and radiation act as mutagens which induce mutation in the fetus
5 desert animals are camel, sand cat, desert tortoises, desert lizards and the great road runner.
<u>Explanation:</u>
- Camel has several physiological and behavioral adaptations that help them survive the extreme conditions of the desert. They have flat feet to help them spread their weight in the sand.
- They have thick eyelashes and closeable nostrils to prevent the entry of sand. They store fat on their humps that supplies energy during long journeys and has a long large intestine which increases water reabsorption.
- Sand cat is similar to the domestic cat in basic appearance but has several adaptations enabling it to survive in the desert. Their paws are covered with thick and long hairs to protect the feet from the heat. They have thick fur that acts as an insulting surface during hot days and cold nights.
- Desert tortoises have excellent water storage capacity. Their bladders are larger than normal and can carry extra water. They have strong feet which helps them to dig holes in the sand and access rainwater.
- Desert lizards can drink water through skin. They do it by a process called cutaneous water acquisition and it helps them to gather water obtained from rainfall, damp sand and pools.
- Great roadrunner has peculiar adaptations. The digestive system of the bird retrieves water from the feces as it is in the excretory canal.
E.coli because e coli is a bacteria.
