Acactus with long spines protects itself from animals better than a cactus with short spines. according to natural selection,

How far down have geologists drilled holes ? (science) a: 3.8 km b: 12 km c: 100 m d: 1200 km

When are the centromeres broken in meiosis?

Which of the following is the smallest unit that would contain a complete copy of the entire human genome? a) one human somatic cell b) one human chromosome c) all of the dna of one human d) one human gene