Question

(i) Food chain
(ii) Growth hormone in human.

Hint:

In a food chain, energy flows from producers to consumers, with energy being lost at each trophic level.

Answer 1

A food chain represents the sequence of organisms through which energy and nutrients flow in an ecosystem. Each organism in a food chain occupies a specific trophic level, starting with producers (usually plants) and moving up to primary, secondary, and tertiary consumers. - Producers: These are organisms that produce their own food through photosynthesis, such as plants and algae.
- Primary consumers: Herbivores that feed on producers.
- Secondary consumers: Carnivores that feed on primary consumers.
- Tertiary consumers: Apex predators that feed on secondary consumers.
The energy from the sun is transferred through the food chain, with energy decreasing as it moves up trophic levels. When an organism dies, decomposers break it down, recycling nutrients back into the ecosystem. (ii) Growth hormone in human.
The growth hormone (GH), also known as somatotropin, is a peptide hormone secreted by the pituitary gland. It plays a critical role in growth, metabolism, and body composition.
- Functions: Growth hormone stimulates the growth of bones and tissues, increases protein synthesis, promotes the breakdown of fats, and helps regulate the body's metabolism.
- Effects on growth: GH stimulates the growth of long bones, particularly during childhood and adolescence. It works by promoting the production of insulin-like growth factor (IGF-1) in the liver, which stimulates growth at the cellular level.
- Disorders: Abnormal levels of GH can lead to disorders such as gigantism (excess GH in childhood) or dwarfism (insufficient GH).
In adulthood, GH helps maintain healthy muscle mass and bone density, while also supporting the body's metabolism.