Unequal crossing over during Prophase I can result in one sister chromosome with a deletion and another with a duplication. A mutated form of hemoglobin, known as hemoglobin Lepore, is known in the human population. Hemoglobin Lepore has a deleted set of amino acids. If it was caused by unequal crossing over, what would be an expected consequence?
A) There should also be persons whose hemoglobin contains two copies of the series of amino acids that is deleted in hemoglobin Lepore.
B) Each of the genes in the hemoglobin gene family must show the same deletion.
C) The deleted gene must have undergone exon shuffling.
D) The deleted region must be located in a different area of the individual's genome.
Answer:
A) There should also be persons whose hemoglobin contains two copies of the series of amino acids that is deleted in hemoglobin Lepore.
Explanation:
The process of crossing over generates recombinant chromatids that carry the exchanged genetic segments. In case of unequal crossing over, a part of the genetic segment is missing from one recombinant chromatid of a homologous chromosome and is inserted into the recombinant chromatid of the corresponding homologous chromosome. The gamete that obtains the chromosome with an additional genetic segment would give rise to a person carrying the duplicated amino acids that are otherwise missing from the chromosome of the person expressing hemoglobin Lepore.
Answer:
The pancreas is an organ located in the abdomen, below and behind the stomach that has a double function:
Endocrine secretion: it produces hormones like insulin and glucagon, as will be seen in the topic of the endocrine system.
Exocrine secretion: produces pancreatic juice, which together with bile mixes with intestinal juice to form chyle.
The liver forms the bile that is stored in the gallbladder.
The bile does not contain enzymes, but bile sales that emulsify fats, leaving them as small droplets that can be attacked by digestive juices.
Answer:
Origin. 20 out of the 36 body plans originated in the Cambrian period, in the "Cambrian explosion", However, complete body plans of many phyla emerged much later, in the Palaeozoic or beyond.
Your nervous system guides almost everything you do, think, say or feel. It controls complicated processes like movement, thought and memory. It also plays an essential role in the things your body does without thinking, such as breathing, blushing and blinking.
The tiny hollow air sacs in the lungs where gas exchange takes place are the "a. alveoli". These are the "last stop" on the respiratory tree and are responsible for oxygen exchange.