The number of mitochondria per cell varies widely; for example, in humans, erythrocytes (red blood cells) do not contain any mitochondria, whereas liver cells and muscle cells may contain hundreds or even thousands. The only eukaryotic organism known to lack mitochondria is the oxymonad Monocercomonoides species.
Dominant' traits will actually disappear faster if they are disadvantageous.
Think about it: if everyone who has even a single copy of a particular allele is at a disadvantage (manifests the phenotype, in this case six fingers), then even single copies are selected against.
In the case of recessive traits, selection occurs only against homozygous carriers, who may be very rare if the allele itself is rare.
A concrete example would be something like Tay-Sachs disease. If the allele that causes this were dominant, every carrier would die before adulthood, and it would occur only as a very rare de novo mutation. But because it is recessive, it persists for now; heterozygous carriers have no disadvantage.
Explanation:
The enhanced greenhouse effect, sometimes referred to as climate change or global warming, is the impact on the climate from the additional heat retained due to the increased amounts of carbon dioxide and other greenhouse gases that humans have released into the earths atmosphere since the industrial revolution.
Answer:
The answer is Covection.
Explanation:
Convection current occurs where hot / warm air rises and cold air drops and replace it.
Facial expressions, body movement and posture, gestures, eye contact, touch, space, and voice.
