Answer:
The two circuits of the cardiovascular system are: Pulmonary Circuit and Systematic Circuit. The pulmonary circuit is shorter than the systemic and is responsible for carrying deoxygenated blood to the lungs from the right atrium, for oxygenation. The systemic circuit is longer and leaves the aortic artery, carrying oxygenated blood throughout the body and nutrients for survival. If less blood were pumped into the systemic circuit, this amount would not be sufficient to compensate for the organism's needs, with the corresponding consequences that this would entail.
It is said that the cardiovascular system is a closed system because blood travels inside a network of blood vessels without leaving them.
codes for a specific trait
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Chromatin
Chromosome, the highest packing level of DNA, is packed in nucleus. DNA strand itself is packed in chromatin. Chromatin is DNA packaging into 30nm fibers that involve DNA strand with scaffolding around DNA proteins, like histones, in eukaryotic cells’ nucleus.
Explanation:
The DNA strand is folded into nucleosomes, bead-like structures on the DNA and fold up into the 30nm fibers. During meiosis and mitosis, the chromatin is super-coiled up into thicker fibers called chromosomes. Chromosomes within the nucleus can be viewed by a light microscope in a cell in metaphase.
Learn More:
For more on levels of DNA check out;
brainly.com/question/8157150
brainly.com/question/2207292
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Messenger and transfer RNA
The red-legged frog breeds in ephemeral ponds from January through March. Its relative, the bullfrog, breeds in permanent ponds from late March through May. There are two pre-mating isolation mechanism at play here,
1. Ecological isolation: The habitats are different, hence the individuals of both the species do not meet. Ephemeral ponds are temporary ponds that develop during rainy days, while the permanent ponds are full of water throughout the year.
2. Temporal isolation: The time of mating is different for both the species to avoid contact between the individuals of closely related species. Red-legged frogs mate in January to March slot and the bullfrog in the March to May slot.