2007-01-08 12:10:41 · 5 answers · asked by STORMY K 3 in Science & Mathematics ➔ Botany
Self-preservation
2007-01-08 12:13:36 · answer #1 · answered by Joe D 6 · 0⤊ 0⤋
Regular plants such as roses have a solid apendage called a thorn to protect themselves and cacti have a hollow apendage called needle to not only protect themselves but also to store water for hydration.
2007-01-08 12:15:43 · answer #2 · answered by ru2tipsy2c 3 · 0⤊ 0⤋
Cacti ARE plants.
Thorns, needles, and other structures are adaptations for protecting the plant from predators.
2007-01-08 12:14:11 · answer #3 · answered by ecolink 7 · 0⤊ 0⤋
for protection from getting eaten, its the same reason porcupines have they're needles, and some lizards are poisonous.
2007-01-08 12:16:02 · answer #4 · answered by aaron m 1 · 0⤊ 0⤋
thorns are modified branches; spines are modified leaves
2007-01-08 12:25:10 · answer #5 · answered by ivorytowerboy 5 · 0⤊ 0⤋