Explanation:
a) True. The bigger the difference, the steeper the concentration gradient and the faster the molecules of a substance will diffuse.
b) True. Active transport requires cellular energy to achieve this.
c) False. Diffusion is the net movement of molecules from an area where they are at a higher concentration to areas where they are at a lower concentration.
d) True. For diffusion to work, the particles must be able to move around.
e) True. Osmosis requires energy from respiration to be carried
out.
f) False. Partially permeable membranes allow only water but not other dissolved substances to pass through.
B) Many animals are captured or killed by poachers, significantly reducing their numbers.
C) Viral epidemics that break out in human populations spread to animals in the ecosystem.
D) Factories cause a significant rise in temperature in the forests, endangering many species.
Answer: A) Urbanization leads to deforestation and loss of habitat for many species.
Explanation:
Urbanization is the main reason for the exploitation of the rain forests which has lead to the extinction of species used to be residing in the forests ecosystems. Following are the factors which are responsible for such disaster with the expension of urbanization:
1. Infrastructure: The land is the main requirement which is responsible for the exploitation of rain forests. The large area is required for the accommodation of the large human population, construction of roads, highways and bridges. This has replaced many habit-ant animals from their native land and also leads to extinction due to ecological disturbance.
2. Increasing needs of food, herbs and wood: Many species of wooden trees could be found in the rain forests which have now extincted due to increasing demand for wood. The herbs have been wiped up for the preparation of medicines and drugs. The large number of tree populations are also exploited due to availability of fruits, and vegetables.
3. Wildlife trafficking and hunting: Some of the animal species have been included in the list of endangered species due to their use for commercial selling of horns, hives and other valuables.
Answer:
A "Pacemaker" can be external or internal and usually generates electrical stimuli to the heart muscle with anelectrode.
Explanation:
Pacemakers allow you to perceive when the heart is beating irregularly or very slowly. This small device sends an electrical signal or electrical impulses to the heart, which makes it beat at the normal rate, because the electrical impulses are transmitted to the heart muscle; by means of an electrode that connects the device with the heart muscle functionally thus an adequate functionality of the heart.
The pacemaker is able to detect heartbeat failures and, at that time, sends an electrical signal through the wires (electrodes) so that the heart contracts.Pacemakers may have more than one electrode depending on the number of areas of the heart that we need to stimulate.
c. dorsal fin
b. gill slit
d. zygote
A hydrogen bond is the electrostatic attraction between polar groups that occurs when a hydrogen (H) atom bound to a highly electronegative atom such as nitrogen (N), oxygen (O) or fluorine (F) experiences attraction to some other nearby highly electronegative atom.