If a person has memory b cells against a certain pathogen, the person is.. a) likely to develop that disease b) much less likely to develop the disease a second time c) able to spread the disease to others through physical contact d) probably still sick with the disease

Plz plz plz quick! 49 points for whoever which of the following statements about greenhouse effect is true? *life on earth is suffering because of greenhouse effect *the greenhouse effect is caused by human activity *all greenhouse gases are harmful *life on earth would not exist without the greenhouse effect

What have we learned from fossil evidence about evolution? a) it is an abrupt change. b)the process is observable. c) it takes place during one lifetime only. d)the most complex traits are always selected.

Look at the photo of the leaf. which term best describes this leaf?