Babies with very low or very high birth weight are less likely to survive. Observe a graph of the data. mc025-1.jpg Which statement is a valid claim that could be made using the data in the graph? Directional selection is occurring because the graph favors an extreme. Stabilizing selection is occurring because the average is favored. Disruptive selection is occurring because the two extremes are favored. Biodiversity selection is occurring because of the greater variation.
Answers
The weight of the new born baby directly affects its chances of survival. In general an under weight baby would be around 3 pounds in body weight. The same is the case with babies that are over weight at the time of birth.
You need to keep in mind that this condition is very rare and occurs in only around 1.5 percent of new born babies. This condition can also get more prevalent in mothers who give birth to more than one baby at the same time.
These babies look very smaller or bigger in size as normal and the flow of the blood in the vessels is also affected on account of this condition leading to risk for their survival.
Complications for premature babies
In general, babies who are born under 36 weeks’ gestation will be admitted to a neonatal unit. Very preterm babies (under 30 weeks’ gestation) and those who require help with breathing will need to be cared for in a NICU.
Larger preterm babies who do not develop breathing problems will be cared for in a special care nursery.
Some of the complications for a premature baby might include:
Lung disease – premature babies often need oxygen via a ventilator or in an incubator until their lungs are fully matured.
Feeding difficulties – premature babies are often unable to suck and need to be fed via a tube into the stomach until the sucking and swallowing reflex is developed.
Temperature control difficulties – the ‘temperature control centre’ in a premature baby’s brain is immature. Babies are therefore cared for under special overhead heaters or in enclosed incubators until they are mature enough to be cared for in a normal cot.
Apnoea – this is when the baby’s breathing stops for a short period of time. Breathing is controlled by a part of the brain called the respiratory centre, which is immature in premature babies.
Bradycardia – is a slowing down of the heart rate, usually caused by apnoea.
Jaundice – the skin takes on a yellow colour, due to a compound in the blood called bilirubin, which breaks down red blood cells. A premature baby’s liver is too immature to process the bilirubin properly, so phototherapy lights are used.