Answer:
50%
Explanation:
If black is dominant to white color and crossing with parents produced some progeny which were black and a white progeny then it simply indicates that parents were heterozygous for the trait even if phenotypically they appeared black. A cross between parents is shown as under:
Parents
Bb x Bb
Progeny: BB Bb Bb bb
BB and Bb allelic combinations produced a black mice while bb combinations produced white mice.
Now the subsequent cross between one of the parents and white off spring is shown as under:
Bb x bb
Progeny: Bb Bb bb bb
It is clear from the cross above that the progeny with Bb allelic combinations will be black while with bb combinations they will be white. 2 out of the 4 progeny are genotypically bb that means they are white i.e. 50% progeny are white.
Answer:
Three Adaptive features of aquatic plants (hydrophytes) are as follows: a) Underdeveloped conducting tissues (xylem and phloem) are present. b) The plants body covered with waxy substance. c) The stems are long, soft and spongy.
Explanation:
a. When sensory information is detected by a sensory receptor, sensation has occurred. TRUE
For example, light that enters the eye causes chemical changes in cells that line the back of the eye. These cells relay messages, in the form of action potentials, to the central nervous system.
b. All sensory systems have absolute and difference thresholds. FALSE
Absolute threshold refers to the minimum amount of stimulus energy that must be present for the stimulus to be detected 50% of the time.
c. Sensory receptors are specialized neurons that respond to specific stimuli. TRUE
d. Sensation refers to the way sensory information is organized, interpreted, and consciously experienced. TRUE
Sensation is input about the physical world obtained by our sensory receptors, and perception is the process by which the brain selects, organizes, and interprets these sensations.
Parasympathetic nerves govern involuntary actions such as pupil dilation, peristalsis, gland secretions, etc.
