Aparticle can infect humans and make them sick. it attaches to a host cell and injects its dna, which the host uses to make proteins for the particle. this particle cannot reproduce on its own and can only copy itself by using the machinery of the host. which explains whether the particle described is a virus or a cell?

Agroup of students is studying convection current. they fill two identical balloons with the same amount of helium. one balloon is placed in a freezer and the other is in an area with warm air. after 10 minutes, the balloon are released from a height of 1 meter. which of the following to the students most likely observe? a) the warm balloon expands and rises. the cold balloon shrinks and sinks b) the balloon both rise. the cold balloon is larger than the warm balloon c) the cold balloon expands and rises. the warm balloon shrinks and sinks d) the balloon rise at the same rate. both balloons are the same size

Chromosome 17 is made of over million base pairs.

Why do oxygen have a strong attractive force for electrons