What combination of sex chromosomes is shown in the image?

Will someone me with this.. specialized cells which perform a particular function form: tissues organs or organism

This rapid change in species that rarely leaves behind fossil evidence is referred to as

The serengeti plains are part of the african savanna ecosystem and are home to a variety of different species of plants and animals. the serengeti plains experience a seven-month period of seasonal drought each year, during which the ecosystem receives only four inches of rain and the availability of some resources becomes very scarce. which type of limiting factors does the seasonal drought in the serengeti plains affect?