Human activites have greatly increased carbon dioxide levels in the atmosphere and nitrogen levels in the biosphere. Altered Altered biogeochemical cycle combined with climate change increase the vulnerability of biodiversity, food security, human health, and water quality to a changing climate.
Answer:
The correct answer is a. absent spinal reflexes below the level of injury.
Explanation:
Spinal shock strictly refers to the neurological condition that occurs immediately after a spinal cord injury, in which the loss of not only motor and sensory functions occurs, but also the abolition of all reflexes below the injury (reflexes of muscular or myotatic stretching and cutaneous reflexes). There is also flaccidity, loss of reflexes. It is characterized by hypotension associated with cervical or upper thoracic spinal injuries. This characteristic shock results from the lesion of the descending sympathetic pathway in the spinal cord, producing a loss of vasomotor tone and sympathetic innervation of the heart. This causes vasodilation of the affected area with accumulation of blood and a decrease in venous return to the heart as well as cardiac output.
The answer would be 25%
Carbon 14 is radioactive material with 5700 year of half-time which will change it into carbon-12, a more stable substance. If the age of the fossil is 11,400 years old, then the amount of half-time passed would be: 11,400 years/ (5,700years/ half-time)= 2 half-time.
Since it undergo 2 half-time, the percentage should be: 100% * (1/2)^2= 25%
(A nebula)
is a cloud of gas (hydrogen) and dust in space. Nebulae are the birthplace biths. There are different types of nebula. An Emission Nebubla such as Orion nebula, glows brightly because the gas in it is energised by the stars that have already formed within it.
(A star)
is a luminous globe of gas producing its own heat and light by nuclear reactions (nuclear fusion). They are born from nebulae and consist mostly of hydrogen and helium gas.
(red giant)
This is a large bright star with a cool surface. It is formed during the later stages of the evolution of a star like the Sun, as it runs
out of hydrogen fuel at its centre.
(red dwarf)
These are very cool, faint and small stars, approximately one tenth the mass and diameter of the Sun. They burn very slowly and have estimated lifetimes of 100 billion years.
(white dwarf)
This is very small, hot star, the last stage in the life cycle of a star like the Sun. White dwarfs have a mass similar to that of the Sun, but only 1% of the Sun's diameter; approximately the diameter of the Earth.
(Black holes)
are believed to form from massive stars at the end of their life times. The gravitational pull in a black hole is so great that nothing can escape from it, not even light. The density of matter in a black hole cannot be measured.
