Question

If you try to throw a basketball into a basket, the likelihood of succeeding depends on the size of the basket. It is more likely that you will get the ball into the basket if the basket is bigger. In your own words, explain how this analogy applies to the idea that the likelihood of crossing over is greater when two genes are far apart than when they are close together.

Short answer

The basketball and genes analogy applies as follows: Just as you have a better chance of making a shot with a larger basketball hoop, there is a greater chance for crossing over to occur when genes are far apart. This is because when genes are distant, there is a greater variety of points where crossing over can occur, similar to how a larger hoop provides a larger 'target' for the ball.

Step-by-step solution

Understand the analogy

First, it is paramount to understand the initial analogy given: scoring a basket is easier when the basket is bigger. This is because there is more space for the ball to enter, making it a higher probability event.

Apply the analogy

In genetics, 'crossing over' refers to the process where two chromosomes swap sections of their DNA - effectively, genes get mixed, creating genetic diversity. If two genes are close together on the chromosome, they're like a small basket - it's less likely for a 'hit' (or a swap/crossover) to occur. However, when the genes are far apart, it's like a large basket - there's a greater chance of a 'hit' happening. In both cases, the larger the 'target,' the higher the probability of hitting it.

Finalize and communicate the analogy

To put it together, when genes are far apart on a chromosome, the 'basket' for genetic recombination is larger. More variations of gene combinations can occur, leading to a higher likelihood of crossing over taking place. Similarly, a larger basketball hoop allows for more successful shots due to the increased margin for error. The 'shots' in genetics are the processes leading to recombination, and the larger 'hoop' represents the larger gene-to-gene distance which increases the likelihood of a successful 'shot,' or recombination.