Heart rate in black worms with and without added glucose
The circulatory system is important in circulating blood, nutrients, oxygen and chemicals to the body. A circulatory system commonly consists of the fluid it contains, such as blood, a pumping vessel such as a heart, and the vessels, which carry the fluid through the body. In a closed circulatory system, the fluid, blood, is contained within the vessels as it circulates through the body. The Lumbriculus variegates, or blackworm, is commonly found in stagnant water along the edges of marshes and ponds. Blackworms have a closed circulatory system, which in the blackworm includes a large dorsal blood vessel . Glucose is the most common carbohydrate and is classified as a monosaccharide and is a reducing sugar. Glucose is called blood sugar as well because it circulates in the blood. When blood glucose is high, the pancreas releases insulin, which then helps to transport glucose into muscle or liver cells. There, it's used for energy. If there's more glucose present than needed, insulin helps the glucose to be stored in adipose tissues as fat for potential future energy needs. One immediate effect of the breakdown and conversion of glucose into cellular energy is an increased metabolism, which can manifest itself in the form of increased heart rate, high blood pressure or some other form of arousal such as heightened mental alertness .
If the black worms are placed in a glucose solution, breakdown and conversion of glucose will be inhibited and cause their hearts to beat faster. In this experiment, it was hypothesized that when black worms were exposed to a solution of 1mM glucose, their average pulsation rate per minute would increase.
The procedure of Lab 7 was the same as Lab 6 – Part B except the black worms were exposed to a glucose solution before their pulsation rates were measured.
In this experiment black worms that were exposed to...
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