| Course | PS220 Child and Adolescent Psychology |
|---|---|
| Unit | Unit 4 |
| Paper type | Prenatal development and genetics paper |
| Length | About 560 words, 5 pages double-spaced |
| Format | APA 7 student paper |
| School | Purdue University Global |
| Program | BS in Psychology |
| Updated | October 2026 |
Free sample paper for PS220 Unit 4
Before Maya Was Born: A PS220 Unit 4 Paper on Prenatal Development, Genes and Environment
[Student Name]
Purdue University Global
PS220: Child and Adolescent Psychology
Unit 4 Prenatal Development and Genetics Paper
[Instructor Name]
[Date]
Maya's family history is composite; the research cited is real.
Three Periods
Textbooks split the months before birth into three stretches (Berk, 2013). In the first two weeks, the germinal stretch, the zygote multiplies into a ball of cells and burrows into the lining of the womb. The embryonic period, weeks three through eight, is when the major organs and structures form, including the beginnings of the nervous system; it is the period of greatest vulnerability to harmful exposures. From the ninth week until delivery, the fetal stretch, the body mostly enlarges and fine-tunes what already exists, including rapid brain development in the final months.
Genes: Maya's Starting Point
Maya inherited half her genes from each parent. Many traits she will show, from height to temperament, are influenced by many genes acting together and by environment, not by single genes. Her family history includes type 2 diabetes on her mother's side, which raises her own long-term risk but does not determine it.
A Wedding Toast in the Fourth Week
At about four weeks, before she knew she was pregnant, Maya's mother drank a glass of wine at a cousin's wedding. When she learned of the pregnancy, she worried. Alcohol is a teratogen: it crosses the placenta and can disrupt developing cells, especially in the nervous system. Fetal alcohol spectrum disorders are more common than once believed; a study of first-grade children in four U.S. communities estimated rates between about 1 and 5 percent (May et al., 2018). Risk rises with the amount and timing of exposure, and because no safe level has been established, health authorities advise avoiding alcohol entirely during pregnancy. A single drink early in pregnancy is unlikely to cause the patterns seen in fetal alcohol syndrome, which are associated with heavier exposure, but her mother's obstetrician used the moment to discuss avoiding alcohol for the rest of the pregnancy.
Timing matters as much as exposure: the embryonic weeks are when structures are being built.
Gestational Diabetes in the Third Trimester
In the third trimester, Maya's mother developed gestational diabetes. Higher blood sugar crosses the placenta, and the fetus produces more insulin in response, which can increase growth and has been tied to heavier weight and diabetes in the child years afterward. With diet changes and monitoring, her mother's blood sugar was controlled. Here a genetic tendency in the family and an environmental condition in the womb worked together.
Epigenetics: How the Womb Can Leave Lasting Marks
Some prenatal influences change how genes are expressed without changing the genes themselves. Heijmans et al. (2008) studied adults who had been exposed in the womb to the Dutch Hunger Winter famine of 1944 and 1945. Six decades later, those exposed early in gestation showed different methylation of a gene involved in growth than their unexposed siblings. Findings like this suggest that prenatal conditions can shape development through lasting changes in gene regulation.
What Maya's Prenatal Story Shows
Maya's development began with both a genetic inheritance and an environment that responded to her mother's choices and health. Neither genes nor environment acted alone, and the timing of each influence mattered.
References
Berk, L. E. (2013). Child development (9th ed.). Pearson.
Heijmans, B. T., Tobi, E. W., Stein, A. D., Putter, H., Blauw, G. J., Susser, E. S., Slagboom, P. E., & Lumey, L. H. (2008). Persistent epigenetic differences associated with prenatal exposure to famine in humans. Proceedings of the National Academy of Sciences, 105(44), 17046-17049. https://doi.org/10.1073/pnas.0806560105
May, P. A., Chambers, C. D., Kalberg, W. O., Zellner, J., Feldman, H., Buckley, D., Kopald, D., Hasken, J. M., Xu, R., Honerkamp-Smith, G., Taras, H., Manning, M. A., Robinson, L. K., Adam, M. P., Abdul-Rahman, O., Vaux, K., Jewett, T., Elliott, A. J., Kable, J. A., . . . Hoyme, H. E. (2018). Prevalence of fetal alcohol spectrum disorders in 4 US communities. JAMA, 319(5), 474-482. https://doi.org/10.1001/jama.2017.21896
PS220 Unit 4 instructions, in plain terms
PS220's fourth unit often asks how genes and the prenatal environment interact to shape development before birth. Describe the germinal, embryonic and fetal periods and what happens in each, noting when the developing child is most vulnerable. Explain genetic influence in terms of many genes and environment working together rather than single genes determining traits. Discuss at least one teratogen with current research on its effects and on the role of timing and dose. Include gene-environment interaction and epigenetics with a well-described study. A case, real or composite, helps show how these influences come together in one pregnancy. Cite a developmental text and research articles in APA style, reporting findings accurately.
How the PS 220 Unit 4 example is put together
The paper outlines the three periods and the vulnerability of the embryonic weeks. A genes section explains polygenic traits and a family diabetes tendency. The wedding toast section explains alcohol as a teratogen, May and colleagues' prevalence estimates, timing and dose, and the obstetrician's advice, under a highlighted line that timing matters as much as exposure. Gestational diabetes in the third trimester illustrates gene and environment acting together. An epigenetics section describes Heijmans and colleagues' comparison of famine-exposed adults with their siblings. The close states that neither genes nor environment acted alone. Each section returns to Maya's mother and her pregnancy, so the science is always attached to dates, choices and outcomes a reader can follow, and the conclusion ties the three periods to the two episodes.
Reading the PS220 Unit 4 grading rubric
Credit depends on accurate prenatal science and clear treatment of interaction. Instructors check that the three periods and the timing of vulnerability are described correctly. Teratogen discussions earn credit when they report current research, including dose and timing, without exaggeration. Explaining genetic influence as polygenic and environment-dependent shows understanding beyond single-gene thinking. Epigenetic research should be described with its design and limits. A case that brings these elements together demonstrates application. Respectful handling of a pregnant person's choices, without blame, is valued. A developmental text and primary research, accurately cited, complete the paper. Explaining why the embryonic weeks matter most, with an example, often decides the top grades.
PS220 Unit 4 help: mistakes that cost points
The most common slip states that a single drink causes fetal alcohol syndrome, or the reverse, that small amounts are known to be safe; the research supports neither claim, and guidance is to avoid alcohol. Another is describing genes as blueprints that determine traits. Students often mix up the embryonic and fetal periods. Epigenetics is sometimes presented as changes to DNA itself. Some papers moralize about the parent's choices. Before submitting, check the weeks for each period, report a teratogen's effects with dose and timing, describe epigenetics as changes in gene expression and keep the tone factual rather than judgmental. Those steps protect the paper from the errors instructors mark most often in this unit.
Get a PS220 Unit 4 example written to your instructions
Share the topic and the instructions with the rubric. A custom paper explains prenatal stages, genetic influence and environmental risks. It arrives within 24-48h; first requests are free. The paper above is an original model document written by our desk, not a submitted student paper and not an official Purdue University Global document.
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PS220 Unit 4 questions, answered
What is a teratogen?
An environmental agent, such as alcohol or certain infections, that can harm prenatal development.
What is epigenetics?
Changes in how genes are expressed, influenced by environment, without changes to the DNA sequence.
Is there a safe amount of alcohol in pregnancy?
Major health authorities advise none, since no safe level has been established.
Where can I find a free PS220 Unit 4 sample paper?
Read the whole PS220 Unit 4 paper here, which follows a composite pregnancy through the prenatal periods, a teratogen and gestational diabetes.
Is any alcohol safe in pregnancy according to the PS220 Unit 4 sample?
No safe level has been established, so health authorities advise avoiding alcohol throughout pregnancy.