This happens even when not crying. The eye is not red and the eyelid is not swollen. Both sides are blocked in 30% of these children. Caused by blockage of the lacrimal duct. This duct carries ...

By contrast, adaptive immunity, which involves lymphocyte-like cells and the antigen-binding receptors they express, is restricted to vertebrates. A major departure in adaptive immunity is evident ...

Model vertebrates are extensively studied non-human vertebrates (species with a notochord, or vertebral column) chosen for the ease of investigating particular biological phenomena in areas such ...

The Little Mountain fire erupted Wednesday in San Bernardino County. (San Bernardino County Fire Protection District) ...

This protects their body a bit like a suit of armour. Vertebrates have a backbone inside their body. They include mammals, birds, fish, amphibians and reptiles.

Classification is putting things into groups. Living things can be divided into these groups or 'classified' by looking at similarities and differences between the way they look and behave. Have a ...