DEFINITIONS & KEY POINTS FOR OBJECTIVES
DEFINITIONS & KEY POINTS FOR OBJECTIVES TERMS DEFINITIONS Cutely In this case, numbers of cells are constant in the entire animal and in each given organ in all…
DEFINITIONS & KEY POINTS FOR OBJECTIVES TERMS DEFINITIONS Cutely In this case, numbers of cells are constant in the entire animal and in each given organ in all…
FURTHER PHYLOGENETIC CONSIDERATIONS The aschelminths are diverse animals. They have common cuticle, pseudocoelom, muscular pharynx and adhesive glands. But no distinctive features in every phylum. 1. Origin of Rotifers The…
PHYLUM PRIAPULIDA (priapos, phallus, Creek god of reproduction symbolized by the penis) 1. Habitat: The priapulids are a small group. It has only 16 species of marine worms found in…
PHYLUM LORICIFERA (Lorica, clothed in armor + ferro, to bear) The phylum Loricifera is a recently described animal phylum. Zoologists have described !about 14 species of Loriciferans. Its first members…
PHYLUM ACANTHOCEPHALA (akantha, spine + kephale, head) 1.Habitat: Adult acanthocephalans are endoparasite in the intestinal tract of vertebrates (especially fishes). They complete their life cycle in two hosts. The juveniles…
PHYLUM NEMATOMORPHA(nema, thread + morphe, form) Nematomorphs are a small group of about 250 species. They are elongated worms. They are commonly called horsehair worms or Gordian worms. Habitat: The…
(a) cnidarians' (b) platyhelminths (c) nemerteans (d) nematodes and (e) annelids. (a) Cnidarians The nerve cells of Hydra contain a growth promoting hormone that stimulates budding, regeneration, and growth. For…
Steroid hormones stimulate the protein synthesis, because steroid hormones pass easily through the plasma membrane, their receptors are inside the target cells. After being released from a carrier protein in…
Hormones modify the biochemical activity of a target cell or tissue. Two basic mechanisms are involved. Fixed - Membrane - Receptor Mechanism The fixed - membrane - receptor mechanism, applies…
At the cells of the target organ, the hormone acts as a "first or extracellular messenger", binding to a specific receptor site for that hormone on the plasma membrane. The…