A neuron is in a Polarized state when the gates of the membrane are closed, and there is slight negative charge inside the membrane The neuron does transmit signals, during this time. The positively charges ions are found outside the cell, and negative ions are inside the cells.
Answer:
According to Punnett Square, what can be concluded from Huntington's disease is that the disease is autosomal dominant.
Explanation:
Huntington's disease is characterized as a neurodegenerative condition, which affects body movements and progressively decreases some higher brain functions.
Inheritance plays a determining role in Huntinton's disease, being a disease transmitted from parents to children with an autosomal dominant pattern, that is, all <u>individuals with the defective gene (H) will have the disease</u>, while the <u>absence of the gene (rr) also guarantees the absence of this condition</u>.
The other options are not correct because:
- <em>Inheritance of Huntington's disease is not sex-linked.
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- <em>The allele that determines the Hungtinton's disease is not recessive.</em>
Answer:
Salut!
- Light enters the eye through the cornea.
- Light travels to the macula within the retina.
- Rhodopsin absorbs light, and the Vitamin A changes shape.
- Vitamin A detaches from the rhodopsin, and some vitamin A is lost.
- Vitamin A from the bloodstream replenishes what is lost. The vitamin A returns to its original shape.
Explanation:
Retina is the part of the eye that contains photosensitive cells that capture light and produce the electrical signals that the brain perceives as images. These photosensitive cells are of two kinds:
Rods contain the photosensitive pigment, rhodopsin that is needed for vision at night or in dim light. Cones function in bright light.
Rhodopsin Bleaching:
Vision in bright or excessive light requires a process called rhodopsin bleaching which is the degradation of rhodopsin upon exposure to light. Upon contact with light, rhodopsin goes through structural changes characterized by the conversion of a pigment derived from Vitamin A, 11-<em>cis</em> retinal to all <em>trans</em> retinal. This chemical conversion initiates a photo-transduction reaction (reaction in which a photon of light is converted into electrical signals) that produces the electrical signals that travel to the brain via the optic nerve. The brain converts the electrical signals to images. This is followed by rhodopsin regeneration in the dark in which all <em>trans</em> retinal is converted back into 11 <em>cis</em> retinal.
The cerebellar <span>vermis</span> receives somatosensory information and influences the vestibulospinal and reticulospinal tracts.
<u>Answer</u>: Sperm cell
<u>Explanation</u>:
Amongst all the 4 options given, only the Sperm cell is a gamete (sex cell) while all the three are somatic cells.
- A <em>somatic</em> cell is the one which forms the body of an organism and contains all the genetic information.
- A <em>gamete</em> is the one which is required for the purpose of fertilization. A gamete of male fuses with the gamete of female in a process called fertilization to form a zygote to give rise to a new individual.
- A Sperm cell is basically a <em>male gamete.</em> It contains only half the amount of genetic information as the other half is contributed by the female gamete.
- This difference in the amount of genetic information arises due to the type of cell division that occurs. The somatic cells undergo mitosis whereas a gamete requires meiosis to occur for its formation.
- During mitosis there is a single round of cell division which divides the parent cell into two daughter cells each with the <em>complete genetic information</em>.
- During meiosis the cell undergoes two rounds of cell division such that a total lf 4 cells are produced each <em>with half the amount of genetic material </em>as present in the parent cell.
Since, <em>sperm is a male gamete and is formed by meiosis it contains only half the genetic information as compared to the other cells.</em>
