The endocrine system works with the nervous system to regulate and coordinate body functions. While the nervous system works quickly and sends messages directly to specific body parts, the endocrine system takes a longer time to produce a longer- lasting effect. The system operates by releasing chemical messengers called hormones into the bloodstream, which travel throughout the body. Eventually the hormone reaches a target organ or tissue to cause an effect. Growth and development, sexual maturation and reproduction, metabolism and homeostasis are some of the processes regulated by endocrine gland secretions.
Endocrine effects can last hours, days, or even years. Adrenalin is a hormone secreted by the adrenal glands that helps the body deal with stress. It produces the emergency, or “fight or fight,” response and is secreted when sudden stress such as fear, pain, anger, or extreme physical exertion requires a burst of energy. Adrenalin causes increases in metabolic rate, breathing rate, heart rate, blood pressure, sweating and even blood clotting.
It is a convenient hormone to study because its effect is relatively swift.
Materials required Materials list Daphnia culture, medicine dropper, slides, cover slips, bristles or threads, paper and encircle, paper towels, aquarium water, “recovery” beaker, dropper bottles containing adrenalin in various concentrations, microscope. Method 1) With a clean medicine dropper, remove a daphnia from the aquarium. Place it in a small drop of aquarium water on the center of a slide. Add two bristles or thread to the slide to limit the movement of the animal. Then place the cover slip over daphnia. Your setup should look like that in Figure 1.
Figure 1 2) With the low-power objective, locate the transparent heart of the daphnia. It is a beating found almost midway in the back. See Figure 2. Observe the animal for a few minutes until it calms down. Figure 2 3) Determine the heartbeat rate over a 1 5-second period. Your partner should tell you when to start and stop counting. If the heart is beating too fast count every other beat and multiply by two. Another method of counting is to tap a pencil on a clean sheet of paper each time the heart beats. After 1 5 seconds, count the number of pencil marks.
Trial 1 a. Record the number of heartbeats per 15 seconds in Table 1. Multiply this number by 4 to get the number of heartbeats per minute. Record this number in Table 1 . 4) Repeat Step 3 two more times. Trials 2 and 3 b. Record the number of heartbeats per 1 5 seconds and the number of heartbeats per minute in Table 1 . Average the heartbeats per minute and record this number. 5) Place a drop of the 0. 001% adrenalin solution next to the edge of the cover slip. Touch a piece of paper towel to the other side of the cover slip to draw the solution through.
Add a second drop and draw it through in the same manner. Wait about 20 seconds. Count the number of heartbeats in 15 seconds. Trial 4 c. Record your result in Table 1. 6) Repeat your count of heartbeats two more times. Trials 5 and 6 d. Record your results in Table 1 . Average the heartbeats per minute and record this number. 7) Repeat Step 5 and 6 above using the 0. 01% adrenalin solution. Trials 7-9 e. Record your results in Table 1 . Average the heartbeats per minute and record this 8) Repeat Steps 5 and 6 above using the 0. % adrenalin solution.
Cite this Biology Lab Report on the Effects of Adrenalin on a Daphnia Essay
Biology Lab Report on the Effects of Adrenalin on a Daphnia Essay. (2017, Oct 19). Retrieved from https://graduateway.com/biology-lab-report-on-the-effects-of-adrenalin-on-a-daphnia/