Molluscus - hormones in growth and reproduction, Biology

Molluscus - Hormones in Growth and Reproduction

We know quite well about the endocrine mechanism of growth and reproduction in the freshwater snail Lymnaea stagnalis. This is a gastropod, and such as other gastropods, Lymnea is protandric hermaphrodite. That means, in these groups of animals, male gonads mature first and this is followed through the maturation of the female gonad. The dorsal bodies produce hormones that promote development of both male and female phases of reproductive organs. In the female phase these glands generate pronounced effects. They stimulate maturation, yolk deposition in the eggs, ovulation and oviposition. They as well stimulate growth and differentiation of the female accessory sex organs. In this animal, specific groups of neurosecretory cells of the cerebral ganglia produce a hormone (growth hormone) that stimulates growth and differentiation of the female accessory sex organs. In this animal, specific groups of neurosecretory cells of the cerebral ganglia produce a hormone (growth hormone) which stimulates growth of the body. Conversely the lateral lobes attached to the brain produce a growth-retarding hormone. This hormone not only retards growth of the body but as well causes an increase in egg production. The optic glands of the cephalopod mollusc Octopus control reproduction in the male and female. The glands secrete a gonadotropic hormone at the onset of sexual maturity. This stimulates development of the genital ducts and maturation of germ cells.

Posted Date: 2/4/2013 8:05:13 AM | Location : United States







Related Discussions:- Molluscus - hormones in growth and reproduction, Assignment Help, Ask Question on Molluscus - hormones in growth and reproduction, Get Answer, Expert's Help, Molluscus - hormones in growth and reproduction Discussions

Write discussion on Molluscus - hormones in growth and reproduction
Your posts are moderated
Related Questions
What is the plant hormone remarkable for stimulating flowering and fruit ripening? What are the uses and practical inconveniences of that hormone? The plant hormone notable for

PITUITARY GLAND (HYPOPHYSIS CEREBRI) - It develops from ectoderm of the embryo. The pituitary gland is located just below the hypothalamus. The pituitary gland is situate

Explain Night Blindness - micronutrient deficiencies? Night blindness is the earliest symptom of Vitamin 'A' deficiency. The reduction in the supply of vitamin A aldehyde i.e.

Define the factors effect the Quantity of Human Milk? A large healthy baby who can vigorously suck will induce and obtain much more milk from its mother than a small, sickly or

How do calcium ions participate in muscle contraction? Why do both muscle contraction and muscle relaxation spend energy? In the muscle cells calcium ions are kept within the s

What are the examples of Law of Minimum?

Define the Food and Nutrition Security? In the previous section, we learnt about the trends in production of food grains in the country and their relationship to population gro

Explain the Pregnancy and Obesity? Obesity is associated with increased risk for gestational diabetes, hypertension, pre- eclampsia, perinatal mortality and the need for induce

i need help with to do a pedigree charts.

Compare the modes of intercellular communication used by the endocrine and nervous systems and discuss the functional significance of the differences between the two systems.