I really need help on these questions. someone please help!!

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

Lymphatic vessels remove excess fluid from tissues. often after mammexront( the surgical procedure to remove of all or part of a breast) the lymphatic vessels draining the arm are damaged. explain a consequence of this damage. what can be done to reduce the symptoms?

(amoeba sisters video recap: pedigrees and need