1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
gregori [183]
3 years ago
12

An experiment was designed to investigate the effect of caffeine on the heartbeat of Daphnia magna, or water fleas. These tiny,

aquatic animals are used because their transparent bodies make it easy to see their hearts and measure their heart rates. Two populations of Daphnia were raised, (A) and (B). Both populations lived in tanks of water at the same temperature and received identical amounts of food. Every 2 hours, water fleas from both populations were selected and their heartbeats were monitored. Population (A) had 0.5 g of caffeine given to them five minutes before their heartbeat was checked. Population (B) were given 0.5 g of water and with no caffeine.
Biology
1 answer:
liq [111]3 years ago
8 0

Answer:

This question is incomplete. It is asking to identify the following in the experiment:

Independent variable: CAFFEINE

Dependent variable: HEARTBEAT

Experimental group: POPULATION A, which were given 0.5g of caffeine

Control group: POPULATION B, which were not given caffeine

Constants: SAME TEMPERATURE, SAME AMOUNT OF FOOD, SAME TIME BEFORE CHECKING

Explanation:

Independent variable in an experiment is the variable which is changed or manipulated by the experiment. In this experiment, the independent variable is the CAFFEINE.

Dependent variable is the variable that is measured by the experiment or in other words, the variable that responds to changes made to the independent variable. In this experiment, the dependent variable is the HEARTBEAT measured.

The experimental group of an experiment is the group that receives the experimental treatment (caffeine). In this experiment, the POPULATION A of Daphnia magna, or water fleas are the experimental group because they received 0.5g of caffeine.

On the other hand, the control group is the group that does not receive the experimental treatment. In this experiment, POPULATION B did not receive any caffeine, hence, it is the CONTROL GROUP.

Constant or controlled variable are those variables that the experimenter must keep unchanged for all groups throughout the experiment, in order not to influence the experiment's outcome. In this experiment, the constants are: SAME TEMPERATURE, SAME AMOUNT OF FOOD, SAME TIME BEFORE CHECKING (2hrs)

You might be interested in
A theory of evolution that states that a species evolves in spurts of rapid change and then goes through periods of no change is
Aleksandr-060686 [28]
A theory of evolution that states that a species evolves in spurts of rapid change and then goes through periods of no change is known as <span>punctuated equilibrium.</span>
8 0
3 years ago
Which of the following is true of an adaptation?
bixtya [17]
A it can be lost during an organisms lifetime
8 0
3 years ago
Taking away the surface of the earth to get coal is called______.
ehidna [41]
Strip mining is taking away the surface, literally scraping the surface away to remove coal.
4 0
3 years ago
Read 2 more answers
Which statement is true for both plant and animals cells?
bulgar [2K]

Answer:

Nuclei and vacuole

Explanation:

But in animal cell vacuole are temporary exist

3 0
3 years ago
Choose the answer that best describes a gene.
nasty-shy [4]
I think the correct answer from the choices listed above is option B. A gene is a tightly coiled strands of DNA. A gene is the basic unit of heredity and is made up of DNA. It acts as instructions to make molecules. Hope this answers the question.
7 0
3 years ago
Other questions:
  • Which of the following adaptations to life on land is found in both insects and modern reptiles?
    12·1 answer
  • A unicellular protist is part of which domain
    10·2 answers
  • Ideally, the______should write in the medication log
    10·1 answer
  • : which surgical procedure involves incision of the thyroid gland
    5·2 answers
  • The light independent reactions produce ______________ and _______________ which are used in the light dependent reactions. A) N
    13·2 answers
  • I need to know everything about reproduction and variation for a test. YEAR 9
    13·2 answers
  • What causes tides to occur every 12 hours? A. the moon's revolution. B. the moon's rotation. C. Earth's rotation. D. Earth's rev
    7·2 answers
  • the crust is made of rock and the mental is also made of rocks.if this is so then why the crust os floating on the mental​
    5·2 answers
  • The biome immediately south of the Taiga is the ______.
    8·1 answer
  • HURRRY
    7·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!