Answer:
* They have xylem and phloem.
* They have true roots.
* They grow near water.
Explanation:
Since horsetails are vascular they have vascular tissue (xylem & phloem) and true roots, stems, and leaves. They grow in marshy areas in or near water and can be several feet in height.
1s orbital
Explanation:
The electron has to go into the first energy level, in the 1s orbital. Helium, with two protons, will have two electrons. These are placed one at a time into the 1s orbital. This makes helium a very contented atom.
Answer:
The advantage of shedding broad leaves in the winter is to conserve the energy that needs to expand in order to provide heat to each part of the plant including leaves as in winters it becomes very dry and cold. If they do not shed their leaves they have to spend more energy to spend energy on leaves.
Needles like leaves have a thick cuticle layer that prevents from losing water in dry conditions or conditions with a limited amount of water in the soil. These leaves also help in photosynthesis by capturing more sunlight as they have a larger surface area. These adaptions can live in poor soil, rain and snowy conditions.
The platypus , brown bear , lion and house cat are related cause they are all mammals , but the lion and house are the same family .. hope this helps :)
Answer: (B) Pre-zygotic; post-zygotic.
Explanation:
Prezygotic isolation occurs before fertilization of eggs. It occurs between the two sex gametes and deter sexual reproduction between different species.
However, individuals are considered to be diverge on the phylogeny tree and different species, when they cannot reproduce.
Mechanisms of prezygotic isolation include habitat isolation, gamete isolation, mechanical isolation, behavioral isolation, and mating seasons.
Whereas, postzygotic isolation prevents the formation of fertile offspring. This phenomenon leads to production of an hybrid offspring from different species and this is a form of speciation in nature.
Mechanisms of postzygotic isolation include hybrid inviability, hybrid breakdown, and hybrid sterility.
