Parasitism is when one organism benefits at the cost of it's host. Like fleas on a dog or intestinal parasites to livestock. Fleas and intestinal worms get food and a nice place to livr, while the dogs and the livestock are being leeched off of and malnourished.
Commensalism is when one organism benefits, while the host is left unharmed- but also doesn't really get anything in return, unlike mutualism. Like a shark and remoras (those fish with suction-cup heads & hitchhike). Sharks aren't hurt, but the remoras get free transportation and access to food scraps.
Hope this helps!
Answer is <em>A.) Females inherit the trait from their fathers</em>.
About 95% of the time down syndrome is caused by “trisomy 21.”the person has three copies of chromosome 21, instead of the usual two copies, in all cells. This is caused by abnormal cell division during the development of the sperm cell or the egg cell.
The phrase anatomical position is defined for human anatomy. It is body s<span>tanding upright, facing forward, arms at sides, palms forward, thumbs outward and toes forward.</span>