Almost all cacti are native to the americas, but there is a small, relatively uncommon group of plants closely related to cacti native to tropical western africa. how can we explain this given the information in this chapter?
a) the plants might have floated across the atlantic
b) this might have been caused by divergent evolution.
c) the continents were once connected.
d) all of the above are true.

C) The continents were once connected.

Explanation:

All the continents were once part of the super-continent called Pangaea. Continental drift split it into fragments and led to the formation of the present-day continents. Since all the continents were connected, some of the cacti native to tropical western Africa must have been carried to present-day America.

The cacti populations present in America and tropical western Africa accumulated genetic variations to get adapted to the prevailing environmental conditions. Separation of continents by continental drift led to their geographical isolation and prevented any interbreeding between the populations. Over generations, the cacti present in two continents evolved into separate species.

hey there!

so, when you eat, your teeth chew and grind food into smaller pieces. this is mechanical digestion. then reactions aided by digestive enzymes break down large food molecules into smaller molecules. this is chemical digestion. the two processes change the food into simpler substances that can be used by the body for raw materials and energy.

hope this

tobey

1. a tropical dry forest carries out more rapid nutrient cycling