The correct answer is option A, that is, jaw or jawless fishes.
Agnatha refers to the superclass of jawless fish in the phylum Chordata, subphylum Vertebrata, comprising of both the extinct (conodonts and ostracoderms) and present (cyclostomes) species. It comprises the group of all vertebrates with jaws, that is, gnathostomes.
On the other hand, there are two categories of living fish with jaws. The Osteichthyes (the bony fish) and the Chondrichthyes (the cartilaginous fish). Both the categories of fish comprises of two pairs of lateral fins and a finned tail for impulsion in water.
brain is the organ which does play a role in mechanical or chemical digestion
Answer:
photosynthesis, the process by which green plants and certain other organisms transform light energy into chemical energy. During photosynthesis in green plants, light energy is captured and used to convert water, carbon dioxide, and minerals into oxygen and energy-rich organic compounds.
The roots absorb water and minerals from the soil and anchor the plant in the ground. The stem supports the plant above ground, and carries the water and minerals to the leaves. The leaves collect energy from the Sun and make food for the plant, using an amazing process called photosynthesis.
Explanation:
Heterozygous- a certain gene that can carry two different alleles
Homozygous- a certain gene that carries two copies of the same alleles
Answer:
a. The maternal copy of UBE3A is expressed and the paternal copy is silenced.
Explanation:
When UBE3A chromosome is in neurons, paternal allele is silent and maternal allele is expressed in process of genomic imprinting. In some cases UBE3A is expressed from both paternal and maternal chromosomes. The paternal chromosome is blue whereas maternal chromosome is magenta.
