Answer:
K+
Explanation:
Leak channels are the gated channels that randomly open and close. The plasma membranes have many more potassium ion (K+) leak channels than the leak channels for other ions such as sodium ion. Also, the potassium ion leak channels are leakier than the sodium leak channels and allow exit of more and more K+ from the neurons. This makes the inside the neuron negative at rest and outside becomes more positive. In this way, the leakage of K+ across the K+ leak channels is mainly responsible for maintaining the resting potential.
Answer:
true.
Explanation:
I have a freind that works at nasa and she said it is true.
Answer and Explanation:
The Huntington disease is caused by a mutation in the gene that codifies for the Huntingtin protein (Htt). The mutation produces an altered form of the protein leading to the neuron´s death in certain areas of the brain.
The Huntington disease characterizes for being,
- Hereditary, passing from generation to generation. To express the disease, a person must have been born with an altered gene.
- Autosomal, affecting men and women equally, because the mutated gene is located on an autosomal chromosome.
- Dominant, which means that by getting only one copy of the altered gene coming from any of the parents, the receiving person will express the disease. The mutation in the gene dominates over the normal gene copy.
- Expressed by heterozygosis. Most people affected by the disease are heterozygous, with a normal copy and a mutated copy.
There are just a few cases all around the world (3% approximately) in which the disease is expressed with no family history. The progenitors are not affected by the mutation. These cases are very rare and are called <u>"de-novo" mutations.</u> A new mutation is spontaneously produced and it is not inherited from any of the parentals. It consists of an increase in the number of CAG repetitions. In a normal person, the number of CAG repetitions is less than 35. When there are 40 or more repetitions it occurs the disease. But when there are between 35 and 39 repetitions, the penetrance of the disease is incomplete. This is a "gray zone". Those alleles that fall in the gray zone are unstable and might produce the HD. Individuals with these unstable alleles have a tendency to increase the number of repetitions from generation to generation until the number reaches 40 repetitions and the person expresses the disease. This <u>usually occurs in the paternal germinal line</u>, as it is particularly unstable in sperm and probably meiosis greatly affects their instability, causing an increase in the number of CAG repeats.
False because the third line of defense is specific by identifying the foreign antigen and activating the antibodies that can bind to the invaders and eliminating the spread
The answer is Mullerian mimicry.
Mullerian mimicry is a kind of mimicry in which two or more poisonous animals generate identical presences as a shared protective tool. The theory behind this is that if a predator learns to avoid one of the poisonous species, it will also avoid the mimic species as well.
It is a natural process in which two or more often repugnant species, which may or may not be closely associated and share one or more common predators, have started to mimic each other's cautionary signals, for their communal benefit, as predators eventually learn to avoid all of them.
