Answer:
space
Explanation:
they figured it out going to space and since a star is a small peice of the sun they can't touch it it's impossible without getting heat burns or dying so they ither observe a star using a telescope or went to space for days
Answer:
Phospholipids are able to form cell membranes because the phosphate group head is hydrophilic (water-loving) while the fatty acid tails are hydrophobic (water-hating). They automatically arrange themselves in a certain pattern in water because of these properties, and form cell membranes.
Explanation:
I believe the biosphere is fragile, because over time all of the pollution us humans have made; If its from air pulloution, acid rain or even water pollution. the toxic acids over time have made the biosphere and the ozon layer weaker and more thin. which causes the biosphere to become weaker.
Quick answer: Food enters the human digestive system through the mouth before then moving through the pharynx, esophagus, stomach, intestines, rectum and anus.
Both answers C and D are correct, however, answer D makes more sense.
