Answer:
The chance of a normal couple having a child with down syndrome is 1 to 600 births.
Explanation:
Down syndrome is a genetic flaw that occurs when the fetus is being formed.
A human cell considered normal has 46 chromosomes, divided into 23 pairs. For some unknown reason, an error may occur at the beginning of embryonic development and an extra chromosome is created, which binds to par 21. The result is cells with 47 chromosomes. This causes the said syndrome.
It is important to know that this failure happens at random. It is nobody's responsibility. It has not been proven to date that lifestyle, actions during pregnancy, smoking, drinking, medicines, environmental factors or kinship between the couple can influence this occurrence. She is not contagious either. The likelihood of a normal couple having a child with the syndrome is approximately 1 to 600 births.
Answer:
At the base of Actinopterygii
*This is a unique characteristic of this group.
Explanation:
A peculiar characteristic organ observed in ray-finned fish (as well as in Sarcopterygii, or lobe-finned fish) but not in cartilaginous fish like shark is the swim bladder.
This organ is often described to be a sac containing gas. It helps these set of fish adjust its buoyancy and its position in the water by regulating the concentration of gas present in it.
The swim bladder is formed as a pouch coming off the embryonic digestive tract, and in chondrosteans and holosteans, with a set of teleosts e.g. the eels, it maintains an open pathway to the esophagus. In majority of the bony fish, the swim bladder is totally sealed off, as gas levels in their swim bladder are regulated by producing gas into the bladder via a network of capillaries, the rete mirabile (Latin word for "marvelous net").
The swim bladder is homologous to the lungs of tetrapods. Since they are formed in the same vein. Few fishes that have an open swim bladder employs it as a breathing organ.
A complementary process in nature either adds (options 3, 6, and 7) or removes ( options 4 and 5) carbon dioxide from the atmosphere.
<h3>Complementary processes and it's benefits</h3>
The processes that leads to the addition of carbondioxide back to the atmosphere include the following:
- The eruption of volcanoes.
- Cellular respiration carried out by organisms to release energy from food molecules.
- The use of gasoline to power cars
The processes that leads to the removal of carbondioxide from the atmosphere include:
- The production of energy-rich carbon compounds through photosynthesis.
- The dissolution of carbondioxide in rainwater.
Learn more about photosynthesis here:
brainly.com/question/19160081
Answer:
B There will be blue colonies only
Explanation:
This screen in called the blue white screening. This is a rapid test that allows scientist to check for their insert of choice in the colonies at a glance. The concept is that where the insert is located the <em>lac Z </em>gene in the vector is interrupted and therefor Xgal, a reporter can be produced. Where there are blue colonies being formed the plasmid has self-ligated and the <em>lac Z</em> gene is not interrupted and the X-gal can be formed rendering a blue color.
I think the answer for Q2 is D but i could be wrong. sorry if i am
