11. bill has iron flakes, salt, and water. he puts some of the iron and salt together in a cup and mixes them
together. he makes a table to describe all the different substances he has.
write an x in the boxes in the table that correctly describe each substance. some substances may have
more than one x.
made of made of
substance appearance
atoms molecules
element compound
pure
substance
iron (fe)
black
powder
salt (nacl)
white
powder
water (h,0)
clear
liquid
iron and
salt mixture
black and
white
powder

What is an endocrine function? (apex) a.esophageal glands release mucus into the esophagus b.salivary glands release saliva into mouth c.swear glands release sweat to the skin d.the pineal gland releases melatonin into the bloodstream

What goes in and out of a cell respiration?

Astudy by solloch and et. al., in 2017, gives the map above which shows the frequency of alleles with a ccr5-delta32 mutations over 87 different countries. this mutation deletes the presence of a co-receptor (ccr5) on the outside of human t-cells (lymphocytes). some viruses, such as the one responsible for the black death and human immunodeficiency virus (hiv), require this receptor for attachment to host cells during the infection process. the black death was an epidemic that passed over northern europe during the 14th century killing nearly 60% of europeans. according to this information, which explanation best explains why northern europeans show a greater immunity for hiv than some other parts of the world?