Answer:
B) Alzheimer's disease.
Explanation:
Alzheimer's disease is a neurodegenerative disorder that causes the degeneration and death of brain cells. It is progressive, meaning it occurs gradually over an extended period of time.
Alzheimer's disease occurs when neurons in the brain fail to produce enough neurotransmitters such as acetylcholine which are required for normal communication between neurons in the brain. Acetylcholine plays a vital role in memory retention and recall. Insufficient neurotransmitters causes neurons to begin to die off. This process is known as neurodegeneration.
Neurodegeneration occurs as a result of sticky proteinous lumps that forms hardened layers on the cells in the brain. These abnormal proteins are called beta-amyloid proteins. Also, there are numerous fibres which entangle the nerve cells and are called neurofibrillary tangles.
Alzheimer's disease leads to a gradual decline in thinking, social and behavioural skills and ultimately memory loss and debilitation.
I would say salt. I mean 75 % of water is salt water, which is why we use machines too sort out Salt From Fresh!
Answer:
a The pulmonary artery carries deoxygenated blood.
Explanation:
This is the the only artery that transports deoxygented blood in mammals. specifically it carry deoxgenated blood from the the atria to the pulmonary circulation. That is to the lungs for the exchange of the C02 in the deoxygenated blood with oxygen in the lungs.
The blood thus become oxygenated,and therefore return through the pulmonary veins to the left ventricle.
From the left ventricle ,through ventricular systole,blood is empty into the aorta through the aortic valves into the systemic circulation.
Although,they carry blood away from the heart,but the blood is de oxygenated instead of the usual oxygenated by arteries,They are still regarded as arteries because of convey of blood away from the heart,a typical role of arteries
The answer is a process that selects variation that help survival and that spreads the variation to more offsprings.
The idea is that there is a higher chance of survival if the organisms has certain characteristics and it is more likely to pass on their genes of this characteristic to the next generations.
For example, there's dark colored fish and white fish. In the deep ocean, dark colored fish can camouflage themselves. However, white fish can be seen easily by predators. Therefore, eventually more dark colored fish survives and more offsprings are dark ones.
Frogs are amphibians that are known for their jumping abilities, croaking sounds, bulging eyes and slimy skin. They live all over the world and are among the most diverse animals in the world, with more than 6,000 species.
Frogs substantially outnumber the two other groups of amphibians — salamanders and caecilians. According to the American Museum of Natural History (AMNH) online reference site, Amphibian Species of the World, which is updated in real time, as of late April 2015, there are 6,482 species in the Anura order (frogs and toads), 691 species in the Caudata order (salamanders and newts) and 204 species in the Gymnophiona order (caecilians). Caecilians look like large worms or slick snakes, according to the San Diego Zoo. They have no arms or legs, and live underground in a network of tunnels.
Frogs vs. toads<span>- See more at: http://www.livescience.com/50692-frog-facts.html#sthash.RLUaqcBC.dpuf</span>