Answer:
i dont understand what do you mean. theres a spelling mistake
Explanation:
Answer:
A point mutation can be described as a mutation in which changes occur in a single nucleotide. A nucleotide may get changed, deleted or inserted from the sequence of DNA. Point mutations can be harmless or harmful depending on the nucleotide in which the changes occur.
A change in just one nucleotide can result in the formation of wrong amino acid and hence changed or wrong proteins can be formed. If the original protein was involved in cellular reproduction, then the entire process of reproduction can be affected by a point mutation.
Sickle- cell anaemia is a disease in which the body fails to produce enough healthy red blood cells. This disease occurs due to point mutation. Point mutation occurs where glutamine (GAG) of the β-globin gets changed into valine (GUG). This change causes the haemoglobin to get a deformed structure due to which it is not able to carry out oxygen.
Answer:
a. deterioration of neurons that produce the neurotransmitter acetylcholine.
Explanation:
Alzheimer's disease -
It is a disease associated with memory , it is a type of dementia .
The initial stages of the disease is the remember new things , the day to day task becomes very difficult with time .
During this disease the neurons get deteriorated day by day , which are responsible to produce the acetylcholine .
Hence , the correct statement about Alzheimer's disease is ( a ) .
Answer:
they give the lungs a really big surface area. they have moist, thin walls (just one cell thick) they have a lot of tiny blood vessels called capillaries.
The walls of the alveoli are only one cell thick. This makes the exchange surface very thin - shortening the diffusion distance across which gases have to move. Each alveolus is surrounded by blood capillaries which ensure a good blood supply.Adaptations of the alveoli:
Thin walls - alveolar walls are one cell thick providing gases with a short diffusion distance. Moist walls - gases dissolve in the moisture helping them to pass across the gas exchange surface. Permeable walls - allow gases to pass through.
Explanation:
Have great day
Answer:
(D) Z
Explanation:
Cellular respiration is a catabolic process by which cells produce energy by oxidising respiratory substrates such as glucose. It is a multistage process occurs in cytoplasm and in mitochondria of a cell. The first stage of cellular respiration is called glycolysis or EMP (Embden, Meyerhof and Parnas) pathway. This stage occurs in the cytoplasm of a cell which is labeled by Z in the given image.
