All species have genetic variation.
North American Houde Sparrow

Where do homologous chromosomes exchange genetic material through crossing over?               a.  chlorophyll    b.  centrosomes    c.  centromeres    d.  chiasma

Which best describes how the common cold spreads in the human body? a bacteria burst out of normal cells killing them b viruses replicate inside respiratory cells c bacteria inject dna into normal cells d viruses insert dna into bacteria

Last week i was assigned a thematic. we have groups of three but the people i was assigned with haven't been in school for days. i would appreciate if anyone can me with my thematic . i highlighted most of the important steps and i circled my thematic topic. in desperate need : ( its due on february 19