Answer:
Explanation:
If the disorder is recessive, neither parent has to have the disorder because
they can be heterozygous. The characteristic features of autosomal recessive inheritance is as follows:-
•Appears in both sexes with equal frequency
• Trait tend to skip generations
• Affected offspring are usually born to unaffected parents
• When both parents are heterozygous approx. 1/4 of the progeny will be affected
• Appears more frequently among the children of consanguineous marriages.
The given pedigree follows these features. So the correct option is 'Autosomal recessive trait'.
Please correct me If I am wrong :)
Answer:
a) Teeth arose from the rough scales of ancestral sharks.
b) Skeletal developments leading to the amphibian movement onto land probably evolved from lobe-finned fishes.
d) The anterior gill arch formed the basis for the evolution of the vertebrate jaw.
Explanation:
The animals we know today have physical characteristics that are evolutionary adaptations of characteristics of their ancestors, which have undergone a series of evolutions and modifications over the years giving rise to new species that have resulted in the species we know today. This process of evolutions and adaptations also happened with the ancestral species of fish, which allowed that today, they had characteristics such as teeth and jaws. Many of these evolutions occurred even in different species, such as the evolution that allowed the amphibians to have a skeleton, which evolved from the spine fins of fish.
Every time I would say, but often is the answer as theory should be revised, and also done practically so that you don’t forget the concepts