Agenetic form of "night blindness" (i. e. poor vision in dim light) is caused by mutations in genes encoding rhodopsin kinase (rk) and arrestin. the mutations reduce the dynamic range of light perception, and the affected individuals have a prolonged light response and adapt very slowly to low light (when entering a dark theater room, for example). which of the following mutations do you expect to be the cause? a. loss-of-function rk mutations and loss-of-function arrestin mutations b. loss-of-function rk mutations and gain-of-function arrestin mutations c. gain-of-function rk mutations and loss-of-function arrestin mutations d. gain-of-function rk mutations and gain-of-function arrestin mutations

The answer is A - Loss-of-function RK mutations and loss-of-function arrestin mutations

Explanation:

RK is Rhodopsin Kinase. Rods which are photoreceptors (along with cones) for providing vision to the eyes contain a receptor-protein called Rhodopsin. When light hits the rhodopsin some changes occur which generate electrical signals that are carried through the optic nerve to the brain.

Mutation in Rhodopsin kinase is associated with night blindness

Humans with defects in RK, or its downstream regulator arrestin, have a prolonged light response, incapable of adapting quickly to sudden drops in ambient light intensity

B

Step-by-step explanation: because it can be due to what your eating and your daily routine such as exercising on a daily basis and keep a healthy lifestyle

The supplement seems to be effective, but more trials are necessary.

Explanation:

Took the test and got it right.

A common misconception in statistics is confusing correlation with causation. If two events are correlated, it merely means that they share the same behaviour over time, but it doesn't imply in any way that those event are related by a common cause, or even worse, that one implies the other.

You can find several (even humorous) counter examples online. For example, if you plot the number of reported pirates assault against the global temperature in the last years, you'll se that temperature is rising (unfortunately...) while pirates are almost disappearing.

One could observe this strong negative correlation and claim that hotter climate has solved the pirate issue. Of course this is a joke, but it explains why you shouldn't confuse correlation with causation.

answer:

d

Step-by-step explanation:

A study was done

C. Under particular circumstances that persisted for long periods, each of these structures presented greater costs than benefits

Explanation:

Natural selection is evolutionary mechanism which favors traits (structures, behavior) of an organism that help him survive and reproduce. But, when there are some structures of an organism that are useless, selective pressure acts against them. Structures that don't contribute to an organism’s survival and reproduction, but are not directly harmful will take long time to be eliminated.

If the albino individuals are present at a frequency of about 1 in 10,000 (or 0.0001); then;

aa = 0.0001

a = 0.01

Using Hardy-Weinberg principle of p + q = 1

p + 0.01 = 1

p = 1 – 0.01 = 0.99

Using Hardy-Weinberg equation; p2 + 2pq + q2 = 1

Carriers of albino allele are the heterozygous population (2pq);

2*.099*0.01 = 0.0198

It'd be B, and eating breakfast can also vary. Sometimes people eat unhealthy things, such as bacon and eggs and pancakes.

The frequency of carriers of the albino allele in the population is. If

To solve this problem, we need to consider the Hardy-Weinberg equation which is the following:

p^2 + 2pq + q^2 = 1

where:  p = frequency of the "A" allele

q = frequency of the "a" allele

In other words, p^2 refers to the frequency of the homozygous(dominant) genotype AA, q^2 represents the frequency of the homozygous(recessive) genotype aa, and 2pq represents the frequency of the heterozygous genotype.

In the problem, if q = 0.01, and p = 0.99, then the frequency of carriers is 2pq which then becomes 0.0099 x 2. Thus, the predicted frequency of Caucasians in the U.S. who carry a single albino allele is 0.0198.

Thus, the predicted frequency of Caucasians in the U.S. who carry a single albino allele is 0.0198.