Answer: All the above options are correct about the characteristics of Lumbriculus variegatus.
Explanation:
Lumbriculus variegatus also called the black worm belongs to the phylum Annelida and is used by biologists to illustrate:
-blood vessel pulsations,
-swimming reflex,
-peristaltic crawling behavior,
-giant nerve fiber action potentials.
These studies where carried out on them due to the characteristics they possess. These includes:
-its blood circulates in a closed circulatory system
-Freshwater worm found throughout North America and Europe
-Prefers the shallow habitats found at the edges of ponds, lakes, or marshes
-Feeds on decaying vegetation and microorganisms.
Answer:
By finding recombination frequencies for many gene pairs, we can make linkage maps that show the order and relative distances of the genes on the chromosome ..
<span>This would be a positive reinforcer. These are things like rewards and bonuses that will cause the subject to want to continue the rewarded behavior. The reinforcer does not need to be financial or even tangible. Positive comments and approval can be reinforcers that strengthen associated behaviors.</span>
Answer:
The cells analyzed might be a mosaic of different genomes
Explanation:
The human genome in every cell might not be the same and could give us some misrepresentation of what really happens on our genome. Chromosomal abnormalities are also a very common phenomena to be observed in human cells. For those differences in the genome of the child the test might have identified some altered cells with a type of chromosomal abnormality which was not latter identified or the abnormal cell might be also eliminated by its abnormal nature.
