Discuss why nearly all larger animals have circulatory systems, and describe the differences between the open circulatory system and the closed circulatory system
What will be an ideal response?
Diffusion is too slow for movement of nutrients, wastes, and gases such as oxygen over more than a few cells at a time. Without a circulatory system, animals would have to remain small and/or thin like the flatworms so that all cells are within diffusion distance of the environment for gas exchange or close to the digestive structures for nutrient diffusion. A closed circulatory system does this by relying on diffusion from lots of blood vessels distributing blood that stays mostly confined to the vessels. An open circulatory system allows blood to pour into sinuses to directly contact tissue cells.
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Pathogenicity is the ability
A) of the host to inflict damage on the pathogen. B) of the host to resist damage by the pathogen. C) of the pathogen to inflict damage on the host. D) None of these are correct.
Which of the following statements is TRUE?
A. Interphase chromosomes are loosely compacted, overlapping, and intertwined with each other within the nucleus. B. Interphase chromosomes are loosely compacted and do not associate with histones until the cell is preparing to divide. C. Interphase chromosomes are also known as euchromatin. Condensed, metaphase chromosomes are also known as heterochromatin. D. Radial loop domains are formed due to interactions between 30 nm fibers and intermediate filaments. E. None of these are TRUE
The process of converting the genetic message from DNA into amino acids is called ___________
Fill in the blank(s) with the appropriate word(s).
Which of the following is true?
A. Only eukaryotes have a membrane-bound nucleus B. Only eukaryotes have ribosomes C. Only bacteria have cell walls D. Only bacteria and eukaryotes have a plasma membrane