<span>There are two major theories that will explain on research on colour vision. They are 1. the trichromatic theory also known as the Young-Helmholtz theory 2. opponent-process theory. These two theories explain processes that operate at different levels of the visual system.</span>
Answer:
The options are not given but they are gotten from another websites.
A. Capillaries surrounding the brain have no pores and are surrounded by membranes of astrocyte cells.
B. Capillaries surrounding the brain have pores and are surrounded by membranes of astrocyte cells.
C. Capillaries surrounding the brain have no pores and are not surrounded by membranes of astrocyte cells.
D. Capillaries surrounding the brain have pores and are not surrounded by membranes of astrocyte cells.
The correct answer is option A.
Capillaries surrounding the brain have no pores and are surrounded by membranes of astrocyte cells.
Explanation:
Capillaries surrounding the brain have no pores and are surrounded by membranes of astrocyte cells because
Capillaries are tiny blood vessels in the circulatory system that connect aterioles to venules. They are the most abundant or they are much blood vessels. They can penetrate the tissues of the body which allow passage of food nutrients, oxygen in the body thereby allowing exchange of nutrients and oxygen between the body tissues and the blood.
Capillaries surrounding the brain have no pores and are surrounded by membranes of astrocyte cells while capillaries in the periphery Capillaries surrounding the brain have pores and are not surrounded by membranes of astrocyte cells.
The decay of uranium isotopes is used to provide information about the age of Earth.
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Explanation:</h3>
Isotopes of Uranium U-232, U-233 , U-234 , U-235 , U-236 , U-238 are used as fuel in nuclear reactors or as explosives for nuclear weapons. Uranium 238 is not very radioactive and it constitutes for nearly 99.3% of natural uranium on Earth and has the longest lifetime: its period is 4.5 billion years, about the age of Earth.
Use of radiometric dating techniques help in defining the age of substances (natural or man-made) using the known decay rates of radioactive elements. Each element has an individual decay rate and half life time.
Two Uranium isotopes (U-238 and U-235) are used for radiometric dating. Both the isotopes have different decay rates and half life period. Both are unstable and radioactive. Since two different isotopes produce two different decay clocks (one as a reference to other), it is beneficial in accurately determining the age of samples. The age of earth (rocks or other natural elements) can be easily determined using Uranium isotopes.
I’d say conical shape- coniferous trees are known for this shape.
The correct answer is B. competitive exclusion.
This law refers to the fact that it is nearly impossible for two species to exist in the same place at the same time together, if they are interested in the same resources. If both species need the same thing to survive, one will have to be stronger while the other one will dwindle in number.