Answer:
<u><em>Phosphorus</em></u>
Phosphorus is a chemical element with the symbol P and atomic number 15. Elemental phosphorus exists in two major forms, white phosphorus and red phosphorus, but because it is highly reactive, phosphorus is never found as a free element on Earth.
Explanation:
Brainliest?
Answer:
Selection that acts, over evolutionary time, to enhance traits that increase an individual's ability to mate frequently or with quality partners is known as <u>sexual selection.</u>
Explanation:
Sexual selection : The process through which males and females attempt to maximise their chances of reproductive success is called sexual selection. It is a form of natural selection. Charles Darwin suggested sexual selection. Animals compete with others of the same species for the chance to mate.
<u>For example:</u> Male widow-bird grows exceptional long tail feathers, females lack tail feathers.
Answer:
The correct answer would be d. thymus.
The thymus is a specialized lymphoid organ of an immune system.
It serves as the site for training and maturation of T-lymphocytes or T cells.
It is composed two identical lobes each containing outer region termed as cortex and inner region termed as medulla.
T-cells are first trained and selected in the cortex region via positive selection. In this, T cells which are able to bind to foreign antigens are selected and rest are degraded.
The selected T cells then move in the medulla region where they are selected by negative selection. In this, the T cells which binds to self-antigens are degraded and rest survive to become functional T cells.
Answer:
reptiles
Explanation:
the reptiles is my favorite