Yahoo Answers is shutting down on May 4th, 2021 (Eastern Time) and the Yahoo Answers website is now in read-only mode. There will be no changes to other Yahoo properties or services, or your Yahoo account. You can find more information about the Yahoo Answers shutdown and how to download your data on this help page.
davidbisok
All of the following are places where O2 and CO2 are exchanged in humans EXCEPT?
A. the skin.
B. red blood cells.
C. cell membranes.
D. capillary walls.
E. alveoli.
Please back up your answer, thx =]
2 AnswersBiology1 decade agoMajor Tom is involved in building the international space station. During his spacewalk, a piece of debris?
Major Tom is involved in building the international space station. During his spacewalk, a piece of debris strikes his faceplate and cracks it. Because there is no air pressure in space,
A. the air in his lungs will move out of his body.
B. the air in his lungs will be held in place by the zero pressure.
C. the air in space will move into his body.
D. the lack of air in space will mean the air in his lungs will go nowhere.
Please back up your answer, thx =]
3 AnswersBiology1 decade agoThe polio vaccine injects harmless antigens from the poliovirus into our bodies. As a result, our bodies make?
antibodies against the poliovirus, so that if it ever came into our body, we would be able to fight it off. Such a vaccine would best fit into which category?
A. passively acquired immunity
B. artificially acquired immunity
C. actively acquired immunity
D. innate immunity
E. induced active immunity
Please back up your answer, thx =]
4 AnswersBiology1 decade agoWhy are macrophages considered part of the non-specific response system?
A. Because they don't produce memory cells.
B. Because they kill many different types of pathogens.
C. Because they displays portions of a virus on their surface.
D. Because they induce the production of antibodies.
E. Because they decrease the reproduction of the flu virus.
Please back up your answer, thx =]
2 AnswersBiology1 decade agoB cells are involved in?
A. cell-mediated immunity
B. nonspecific defenses
C. passively acquired immunity
D. antibody-mediated immunity
E. actively acquired immunity
Please back up your answer, thx, =]
2 AnswersBiology1 decade agoYou are examining a microscope slide of an onion root tip looking for samples of cells in the middle of?
mitosis and cell division. You see lots of long, cylindrical cells all looking more or less alike, but no evidence of cell division. Why do you not see cell division?
A. You are looking at the region of elongation.
B. You are looking at the apical meristem.
C. You are looking at trichomes.
D. You are looking at root hairs, which are known to get longer but do not divide.
E. You are looking at the root cap.
Please back up your answer, thx =]
2 AnswersBiology1 decade agoIn a woody stem which of these is not a secondary tissue?
A. wood
B. pith
C. ray
D. bark
E. All of the above are secondary tissues.
Please back up your answer, thx =]
1 AnswerBiology1 decade agoLowering the level of a hedge with a hedge trimmer stimulates the hedge to become bushy because?
A. stimulating the production of ethylene gas.
B. killing the apical meristems makes more auxin which stimulates lateral branch buds to grow.
C. killing the lateral buds results in apical dominance under the influence of cytokinins.
D. killing the apical meristems makes less ethylene which stimulates lateral branches to grow.
E. killing the apical meristems results in less auxin which then allows lateral branches to grow.
Please back up your answer, thx =]
1 AnswerBiology1 decade agoA more or less circular ring of mushrooms appears in your yard, apparently overnight. The circle is several?
yards in diameter. The most likely explanation for this circle of mushrooms is that
A. the mushrooms are all part of the same plant, with mycelia radiating out from the location of a germinated spore.
B. a circle is nature's most perfect shape for asexual reproduction structures.
C. one mushroom in the circle reproduced sexually to make all the other mushrooms in the circle.
D. the mushroom plants in the center of the circle have been eaten by herbivores.
E. mushroom spores were dropped by a circling bird, thus explaining the circular shape of the group of mushrooms.
Please back up your answer, thx =]
4 AnswersBiology1 decade agoBacteria differ from one another:?
A. reproductively
B. structurally
C. metabolically
D. A and C
E. A, B, C
I think it is E. but i'm not 100% any help would be appreciated
Please back up ur answer, thx =]
1 AnswerBiology1 decade agoDNA analysis of these very small cells indicates that they have the?
fewest genes in common with the kingdoms Plantae and Animalia.
A. archaea
B. protista
C. fungus
D. bacteria
E. Two of these are possible.
Please back up your answer, thx =]
3 AnswersBiology1 decade agoAs seen under an optical microscope these cells occur singly, have a nucleus and?
other organelles but do not have chloroplasts or flagella. Even so the cells seem to move by a kind of oozing or flowing of the cytoplasm.
A. protista
B. bacteria
C. fungus
D. archaea
E. Two of these are possible.
Please back up your answer, thx =]
1 AnswerBiology1 decade agoWhich of the following is the most important force in shaping evolution?
A. biological research
B. random events
C. natural selection
D. the fixity of species
E. geological change
Please back up your answer, thx =]
3 AnswersBiology1 decade agoWhen a cutting from a plant sprouts roots and yields a new, independent plant, what process has occurred?
A. meiosis
B. crossing over
C. parthenogenesis
D. vegetative reproduction
E. binary fission
Please back up your answer, thanks =]
2 AnswersBiology1 decade agoWhy does ova production result in one egg and three polar bodies?
A. This allows the egg to receive most of the cytoplasm.
B. This reduces egg size by distributing most of the cytoplasm to the polar bodies.
C. This allows the egg to receive all the chromosomes.
D. This removes Golgi, lysosomes and other organelles from the egg.
E. This creates more polar bodies, which are the cells that will actually be fertilized.
Please back up your answer, thanks =]
1 AnswerBiology1 decade agoIf polar bodies formed during spermatogenesis, how would this affect sperm production?
A. Sperm would swim more efficiently.
B. There would be fewer sperm produced.
C. Sperm would be produced by mitosis instead of meiosis.
D. Sperm would be diploid instead of haploid.
E. All sperm would all be smaller.
Please back up your answer, thanks =]
2 AnswersBiology1 decade agoWhat features are associated with mature sperm?
A. a diploid set of chromosomes in a nucleus, mitochondria, flagellum
B. 23 chromosomes, cytoplasm for the zygote, flagellum
C. a single X or Y chromosome in a nucleus, flagellum, mitochondria
D. a haploid set of chromosomes, polar bodies, mitochondria
E. a nucleus with 22 autosomes and an X or a Y; mitochondria, flagellum
Please back up your answer, thanks =]
2 AnswersBiology1 decade agoA human male has --------?
A. a Y from his mother and an X from his father.
B. 2 X chromosomes, one from each parent.
C. an X from his mother and a Y from his father.
D. two Y chromosomes, one from each parent.
E. an X and a Y, either of which could have come from either parent.
Please back up your answer, thanks =]
3 AnswersBiology1 decade agoCancer is caused by unrestrained division of cells. Best way to control cancer is study the mechanism of the?
Cancer is caused by unrestrained division of cells. The best way to control cancer is to study the mechanism of the
A. cell cycle.
B. environmental system which may cause cancer.
C. cell communication system.
D. cell defense system.
E. None of the above is important.
Back up your answer, thanks =]
5 AnswersBiology1 decade agoWhich below best describes a difference between a chromosome and a gene?
A. A chromosome and a gene are identical.
B. A gene is one section of a chromosome, and a chromosome may carry many genes.
C. A gene is larger than a chromosome.
D. A chromosome contains the entire DNA of a human; while a gene is only a single portion of that DNA.
E. A gene is made of DNA and a chromosome is only made of protein.
Back up your answer, thanks. =]
5 AnswersBiology1 decade ago