Answer:
Option (e).
Explanation:
Meiosis may be defined as the process of cell division in which a single parent cell divides into four daughter cells. The chromosome number reduces to half in meiosis.
Crossing over is the process of exchange of genetic material between the homologous chromosomes of the non-sister chromatids. Crossing over will bring variation in the gametes. Hence, the absence of crossing over results in the formation of gametes with less genetic variation.
Thus, the correct answer is option (e).
Answer:
(a) number of strands (n) = time (t) ÷ proportionality constant (k)
(b) The time needed for the bacterial to double its initial size is 3.36 hours.
Explanation:
(a) Let the rate (time) be represented by t and the amount (number) of strands of bacteria be represented by n
t is proportional to n, therefore, t = kn (k is the proportionality constant)
Since t = kn, then, n = t/k
(b) Initial amount of strands = 300
Amount of strands after 2 hours = 300 + (300 × 20/100) = 300 + 60 = 360
k = t/n = 2/360 = 0.0056 hour/strand
Double of the initial size is 600 (300×2 = 600)
Time (t) needed for the bacterial to double its initial size = kn = 0.0056×600 = 3.36 hours
Answer:
the difference between rocks and minerals .A mineral is a naturally not occurring, inorganic solid with a definite chemical composition and a crystalline structure formed by geological processes. A rock is an aggregate of one or more minerals whereas a rock may also include organic remains and mineraloids.
Explanation:
Answer:
In human vision, the cone visual opsins are grouped into four photoreceptor protein families LWS, SWS1, SWS2, RH2
.
- SWS1: produce pigments sensitive to very short wavelengths, UV-violet, 360-450 nm.
- SWS2: produce pigments sensitive to short wavelengths, blue, 450-495 nm
- RH2: produce pigments sensitive to medium wavelengths, green, 495-560 nm
- LWS: produce pigments sensitive to long wavelengths, yellow-red, 560-770nm.
Explanation:
Photoreceptor proteins are light-sensitive proteins that mediate light-induced signal transduction, thus they are involved in the sensing and response to light in a variety of organisms.
The photoreceptor proteins are classified based on the chemical structure of the chromophores involved, the light absorption and on the protein sequence.
This photoreceptor proteins are located at the cone photoreceptor cells and are responsible of photopic vision.
For scotopic vision, rhodopsin is responsible. Rhodopsins are the visual pigments (visual purple) of the rod photoreceptor cell in the retina. They are responsible of human vision in dim light, as it contains a sensory protein that converts light into an electric signal.
