A. spermatids \nB. secondary spermatocytes \nC. primary spermatocytes \nD. spermatogonia \nE. spermatozoa
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B. Secondary spermatocytes... spermatids are the product of the meiosis II which under go metamorphosis to become spermatozoa, but they don't go through meiosis again
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, process of nuclear division in a living cell by which the number of chromosomes is reduced to half the original number. Meiosis occurs only in the process of gametogenesis, i.e., when the gametes, or sex cells (ovum and sperm), are being formed. Because fertilization consists of the fusion of two separate nuclei, one from each of the sex cells, meiosis is necessary to prevent the doubling of the chromosome number in each successive generation. An ordinary body cell is diploid; i.e., it contains two of each type of chromosome. The members of each pair are known as homologous chromosomes. An ovum or sperm is haploid; i.e., it contains only a single chromosome of each type and, therefore, half the number of chromosomes of the diploid cell. When the two haploid cells fuse, the diploid number is restored, and the plant or animal growing from the fertilized egg (zygote) has the usual diploid number of chromosomes in its cells. Just before meiosis each chromosome replicates to form two identical copies in the form of strands called chromatids joined together at a point called the centromere. In the first stage of meiosis, called the reduction division, the members of each pair of homologous chromosomes lie side by side and crossing over occurs. Each member of the pair then moves away from the other toward opposite ends of the dividing cell, and two nuclei, each with the haploid number of double-stringed chromosomes, are formed. Thus at the beginning of the second meiotic sequence, called the equational division, each cell nucleus contains one chromosome from each homologous pair and each chromosome is of two strands that are identical (except where crossing over has occurred). Then the chromosomes separate into their single strands which move toward opposite ends of the dividing nucleus. The result of meiotic division is four cells, each haploid, with one chromosome of each pair.
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sexual..eggs and sperm\nasexual..fission and cell splitting
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None. They all let sperm come in.
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8. DNA is found in the nucleus\n9. non-sex choromosomes (just kidding, not really sure)\n10.human
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Answer C; all the others have to do with sexual reproduction.
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for internal in external structures and drawings.\nhttp://www.biologymad.com/Kidneys/Kidneys.htm
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Well it comes from the testicles through the vas defference, usually excreted during ....oh... semmen..... my bad.
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they are:\nmouth (buccal) cavity\npharynx\nesophagus\nstomach\nileum\nduodenum\nlarge intestine\nrectum\nanus
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Typical spermatozoa are "normal" meaning no defects. They are formed with and oval shaped head and long flagellate tail (wiggles like a whip) to swim. In other words, they are healthy sperm cells capable of fertilizing an egg.\n\nAtypical spermatozoa have some type of defect; too small, dented or mishaped head, tail is not formed properly, is immobile or very slow moving, can be necrotic or "sick". Would probably not make it all the way to the egg. In other words, a deformed sperm cell.\n\nHope this helps.
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b)Unique to Angiosperms, flowering plants exhibit double fertilization whereby two sperm nuclei are deposited in the female gametophyte with each undergoing a fertilization event. The first sperm nucleus undergoes fusion with the egg cell nucleus forming the zygote while the second sperm nucleus undergoes fusion with the two polar nuclei of the central cell resulting in a triploid cell that proliferates through mitosis giving rise to the endosperm. The endosperm is often a source of nutrition for the developing embryo after fertilization and is often a starchy tissue.
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30) I'd say A.  Because there is a duplication of chromatids in both Meiosis I and in mitosis. It's NOT B for sure because mitosis produces only 2 cells.  It can't be D either, because chromatids are prensent in both processes.\n\n31) They are all happening in both.  so E\n\n40) C because gametes (like sperm and eggs) are cells ready for fecondation.  they only have HALF the chromosome set.\n\n41) I'd go with E.  Homologues are always paired, that is until the anaphase, so A and D got to be right.  Cross over is an exchange of genes between the two homologues, which is C.  The answer E talks of anaphase, which is the breakage of the centromeres.
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Blood. Testicles. Fluid. Semen. Largely, that covers it if you ask me. I am not a doctor, but there is not exactly a whole lot of room for any big objects such as TVs or Stereos.
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To answer your question....yes.  The egg cells of the female all carry X chromosomes.  The sperm cells can carry either X or Y.  So basically, the sex of a mammal depends on the male, and which particular sperm fertilizes the egg (X).  If an X sperm fertilizes the egg, you have XX, which is a female, and if a Y sperm fertilizes it, you have XY, which is male.  This is why some sex-linked traits are more visible in males, such as color blindness, but that's a whole different post.
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Fertilization.\nOr are you asking about what happens in Prophase 1 of Meiosis? Homologous chromosomes, one from each parent pair.
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red blood cells (erythrocytes),  white blood cells (lymphocytes) (lots of different types),  phagocytes, macrophages, platelets (sticky part of blood), stem cells, nerve cells, sperm cells, egg cells, fibroblasts, epithelial cells (ciliated and otherwise), gastric mucosal cells, fat cells, islets of Langerhans (is that right?  pancreas), helper cells (immune system) - will that do to start?
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a- multi\nb-both\nc-both (plants like bacteria and animals)\nd-single celled