SAMPLE APA PAPER FOR STUDENTS 2. Abstract. You may not have to include an abstract with your paper; if in doubt, ask your instructor. The. abstract is a single paragraph in block format (without paragraph indentation) and should be. between 150 and 250 words. Be sure to understand the difference between the abstract (a.
In the XY sex-determination system, the female-provided ovum contributes an X chromosome and the male-provided sperm contributes either an X chromosome or a Y chromosome, resulting in female (XX) or male (XY) offspring, respectively. Hormone levels in the male parent affect the sex ratio of sperm in humans.
The male parent does. Sex is determined by two chromosomes, X and Y. A female is XX, a male is XY. Since women completely lack the Y choromosome, they always contribute an X chromosome to the baby.The sex is determined by whether the sperm that fertilizes the egg is carrying another X or a Y.es | No Thank you! The male parent does. Sex is determined by two chromosomes, X and Y. A female is XX, a male is XY. Since women completely lack the Y choromosome, they always contribute an X chromosome to the baby. The sex is determined by whether the sperm that fertilizes the egg is carrying another X or a Y.