The human heart is a major muscular organ located in the thoracic cavity between the lungs. Its major function is to pump blood throughout the body. A double-layered sac, Pericardium, which is the tough connective tissue protects and anchors the heart. There is fluid between the layer of the sac allow for lubrication of the heart’s continual motions. The inner layer of the sac is the heart wall, which is mainly cardiac muscle. The human heart is made up of two chambers. The atriums receive blood from veins, and the ventricles pump blood into the arteries. For the blood to pass through the an atrium to a ventricle for example, the blood has to pass through a heart valve. Valves control the blood from moving backwards. The “lub-dub” sound made by a beating heart derives from the closing of the atrioventricular (AV) valves, then the concurrent closing of the aortic and pulmonary valves (Starr, 2007). The human heart is also myogenic meaning the heart is independent of an outside stimulus from the nervous system. The sinoatrial (SA) node, pace maker, is responsible for sending electrical impulses through the heart making it contract and pump blood. The human heart is very much affected by the consumption of caffeine. Caffeine can be found in certain coffees, teas, sodas, and chocolates. By consuming caffeine one’s heart rate to dramatically increase and also cause abnormal heart rhythms (Medline Plus: Caffeine, 2012).
Table of Contents
- ASPECT 1: DEFINING THE PROBLEM AND SELECTING VARIABLES
- Background Information
- Problem Question
- Hypothesis
- Hypothesis Explanation
- Variables
- ASPECT 2: CONTROLLING VARIABLES
- Table 1. Controlled variables kept constant
- Experimental Control
- ASPECT 3: DEVELOPING A METHOD FOR COLLECTION OF DATA
- Apparatus and Materials
- Procedure
- DATA COLLECTION AND PROCESSING
- ASPECT 1: RECORDING RAW DATA
- Qualitative
- Quantitative
Objectives and Key Themes
This investigation aims to determine the effect of caffeine from different beverages (coffee, herbal tea, and black tea) on human heart rate. The study hypothesizes that consuming beverages with higher caffeine concentrations will result in elevated heart rates compared to beverages with lower concentrations. The experiment will be conducted with controlled variables to isolate the impact of caffeine on heart rate. Key themes explored in this investigation include:- The physiological effects of caffeine on the human heart
- The role of caffeine as a stimulant and its impact on nerve cell communication
- The influence of caffeine on heart rate regulation and the mechanisms involved
- The importance of controlling variables in experimental design to ensure accurate results
- The application of scientific methodology to investigate a real-world phenomenon
Chapter Summaries
The text focuses on the design and execution of an experiment to investigate the effect of caffeine on heart rate. It starts by defining the problem and selecting variables, including the dependent variable (heart rate) and independent variable (caffeine concentration). It then discusses controlling variables to ensure a valid experiment, outlining key controlled variables such as the time after caffeine ingestion, brewing time, and amount of beverage consumed. The text continues by detailing the experimental method, outlining the apparatus and materials used, and providing a step-by-step procedure for conducting the experiment. The final section focuses on data collection and processing, including both qualitative observations and quantitative data in the form of a table.Keywords
The main keywords and focus topics of this text include caffeine, heart rate, experimental design, controlled variables, stimulants, nerve cell communication, heart regulation, scientific methodology, data collection, and data processing. The study investigates the impact of caffeine consumption on heart rate, highlighting the importance of controlling variables to ensure accurate results and provide insights into the physiological effects of caffeine on the human body.- Quote paper
- Tracey Rosenlicht (Author), 2012, How Caffeine Effects Heart Rate, Munich, GRIN Verlag, https://www.grin.com/document/207849
