A student wants to prove that amphibians appeared on earth before birds. The student should use the fossil findings as evidence to provide the most reliable information about the periods when amphibians and birds appeared on earth. Fossils would throw light on the internal body structures that bear the closest similarity to either the amphibians or the birds. The radiocarbon dating of the fossils will reveal its age. This can be used to figure out the time of divergence of the two types.
Answer:
I think the answer is option 3
Ethonal is produced during b. Alcohol fermentation that converst sugars into ethanol.
Answer:
The human population is yet to reach its carrying capacity. However, the following will suggest that humans have reached their carrying capacity.
1. When humans are unable to increase food production which is expected to sustain a larger population.
2. When humans' use of resources, in general, is greater than resource availability.
Explanation:
The human population is yet to reach its carrying capacity. However, the following will suggest that humans have reached their carrying capacity.
1. When humans are unable to increase food production which is expected to sustain a larger population.
2. When humans' use of resources, in general, is greater than resource availability.
Answer:
Answer is option A.
Orchid bees are to Brazil nut trees as breezes are to pine trees.
Explanation:
In Brazil nut trees, the female orchid bees act as pollinators that help in pollination. In pine trees, wind or breeze helps in pollination.
Pine trees are gymnosperms and so they do not have flowers to attract pollinators like bees or butterflies or birds. They are wind-pollinated. Pine trees are monoecious i.e., both male and female reproductive structures (pine cones) are present on the same tree.
The male cones (catkins) produce pollen grains that are lightweight, less sticky and have air bladders or small wing-like structures. As a result of these features, the pollen grains can be easily carried and dispersed by the breeze. In order to prevent self pollination (pollen falling on the female cones of the same tree), the male cones are normally located on the lower branches of the pine tree.
The female cones are located on the upper branches of the tree and the center of the cone contains eggs or ovules. The pollen grains that are carried by the wind, fall on the female cone of another pine tree. Each pollen grain grows a pollen tube into the center of the cone and the nucleus cell of the pollen travels through the tube and reaches the egg, where it combines with the egg to form an embryo. The embryo eventually grows into a seed. The seeds of pine trees are then dispersed by wind or animals such as squirrels.
