Your assignment is to prepare and submit a paper on childhood depression disorder. Current research has dispelled such a notion and as such many important figures in childhood, psychopathology has taken interest in this disorder.

Childhood depression affects 2-4% of children and about 5-8% of adolescents (Lake & Dulcan, 2011). Researchers worldwide have however found out that the rates of depression are on the rise that there is a trend of earlier ages of onset. The disorder has equal rates of boys and girls during childhood, but favours girls more than boys during the adolescent age by a ratio of 2:1 (Faraone et al. 2005).

Most of the developmental difficulties arising from this disorder can usually be identified at both the home and the school setting. In order to diagnose this disorder, the Diagnostic Statistical Manual – Fourth Edition (DSM-IV) is used. According to the manual, criteria for the diagnosis of massive childhood depression include (Willcutt, 2012):

Confusion usually arises in the field of childhood depression same as adult depression due to different applications of the term “depression” and variation in the method of diagnosis. In childhood depression studies, the term has been used to categorize those with depressed mood, those with a combination of depressed mood plus other symptoms creating a syndrome, or those who have a set of symptoms that have been identified by official diagnostic criteria for a depressive disorder.

Researchers have found out that various genetic, environmental, and social factors can contribute to the onset of depression in children. It has been discovered that there is a link between prenatal and perinatal maternal depression and childhood depression (Glover, 2011). Researchers have found out that fetal exposure to stress and stress hormones may affect infant temperament and may result in childhood depression as the child grows.&nbsp.Pregnant women who are under constant stress, anxiety, and depression have very high levels of endocrine (cortisol) which may be passed on to children, hence causing them to be susceptible to depression during the early stages of development (Lifford, Harold & Thapar, 2008).&nbsp.

Provide a 4 pages analysis while answering the following question: Horseradish Peroxidase. Prepare this assignment according to the guidelines found in the APA Style Guide. An abstract is required.

For each enzyme, there is a small range of pH within which it works optimally. Enzymes have&nbsp.active sites in their structures. The active site is the part of the enzyme that has the correct shape and the functional groups required to bind to the substrate (Dunford, 1999). Enzyme activity can be measured in any one of these two ways: observing the rate at which the substrate disappears during a reaction or measuring the rate at which the product is formed. Enzyme assays are used in such measurements.

Two methods have been developed for use in measuring the number of substrates or products in a chemical reaction: continuous and fixed-timed assays. Continuous essays make use of a spectrophotometer to measure the rates at which the substrate disappears and products form in real-time (Leskovac, 2003). To measure the peroxidase activity a change in the amount of product formed will be evaluated over time. For the breakdown of peroxide by peroxidase, the simplest molecule that can be measured is O2 gas, the product of the decomposition of peroxide.

To accomplish this the real volume of O2 gas produced is measured by the use of an indicator. For this experiment, an indicator (pyrogallol) that shows the presence of O2 gas will be used (Dunford, 2010). 2.50 cm3, 0.35 cm3, 0.10 cm3, and 0.35 cm3 of deionized water, buffer solution (at a pH of 6.0), hydrogen peroxide, and pyrogallol respectively were pipetted into two separate cuvettes labeled Cuvette 1 and Cuvette 2. The contents of the cuvettes were then mixed well using a small glass rod. The spectrophotometer was set to 420 nm after which Cuvette 1 was placed into it. 0.1 ml of the buffer solution was added to the cuvette and then stirred using a small glass rod.

The readings of the spectrophotometer were recorded every 10 seconds for 5 minutes. Cuvette 2 (blank) was placed into the spectrophotometer. 0.1 ml of&nbsp.the enzyme was added to it and stirred using a small glass rod. The readings of the spectrophotometer were recorded every 10 seconds for 5 minutes.&nbsp.