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
ELEN [110]
3 years ago
12

An experiment was designed to investigate if caffeine would raise the heartbeat of water fleas. Two groups of water fleas were u

sed. Both groups were fed the same food, received the same amount of light, and had their temperature maintained at 20°C. Every two hours, water fleas from both groups were selected and their heartbeats were checked. The fleas of group 1 were given caffeine five minutes before their heartbeat was checked. The fleas of group 2 were given nothing. What is the Control Variable?
Biology
1 answer:
fgiga [73]3 years ago
8 0

Answer:

That is administered and controlled

Step-by-step explanation:

A variable is the condition or a product that may vary without the influence of any investigator. Such variables can be found abundantly in our daily lives, ranging from air to sunlight. Controlling such variables ensures the limitation of their influence on the outcome of an experiment. In connection to this experiment, the variables that are controlled are the mineral content in the water, the  amount of bacteria food, the amount of light and the the constant temperature of 20 degrees C.

If not administered or these variables controlled, the experiment would not clearly explain the impact of caffeine on the heart beat of the water fleas as other variables may have influenced it. Thus variables are controlled to study the singular impact of any agent or effect.  

You might be interested in
All movement are locomotion but not all locomotion are movement​
Vladimir [108]
Some may assume that movement and locomotion are the same, but these two words have certain differences. Movement is known to be the time when a living organism will move from one place to another. Locomotion means that the movement that the living organism did has made changes to the current position of the organism.
7 0
3 years ago
If a th reads this, or if destinyawakens goes on this question can u help me, if its anyone else besides him. dont answer this.
Anon25 [30]
<span>The Cerebrum: The cerebrum or cortex is the largest part of the human brain, associated with higher brain function such as thought and action. The cerebral cortex is divided into four sections, called "lobes": the frontal lobe, parietal lobe, occipital lobe, and temporal lobe.</span>
7 0
3 years ago
Read 2 more answers
The various types of cells making up the structural composition of your body (skin cells, muscle cells, cells of your stomach li
Margarita [4]
The various types of cells making up the structural composition of your body (skin cells, muscle cells, cells of your stomach lining, etc.) are all Epithelial cells. The only other class of cells in your body are Gametes (sperm and egg cells).
8 0
3 years ago
Which answer best defines what the Lotka-Volterra predator-prey model mathematically describes?-The competition among many preda
yanalaym [24]

Answer:

The simultaneous effect of a predator population on a prey population and a prey population on a predator population over time.

Explanation:  

The mathematical models of Lotka-Volterra equations explain the existing interaction between species in which prey and predator influence and affect each other. The model follows a few assumptions,    

  • The ecosystem is isolated and closed. There is no migration.
  • The whole individuals are reproductively equivalent.
  • In the absence of the predator, prey shows an exponential growth rate. The prey is in the ideal environment.  
  • When there is no prey, the predator population decreases exponentially because of the lack of food. The predator environment is ideal, but it is limited by prey density.  
  • The predation rate is proportional to the encounters rate, which also depends on density.  
  • The predators affect the prey populations, inducing its decrease proportionally to the number of prey and predators present.  
  • The prey population also influences the predator population proportionally to the number of encounters between the two species.  

In these equations, the variable D is the number of predators, and P the number of prey items.

The parameters are always constant:  

• r1: prey growth rate.  

• a1: predator hunting success.  

• r2: predator growth rate.  

• a2: the success of the predator in hunting and feeding.

In nature, many factors affect interactions, such as dense-dependent factors and dense-independent factors. Also, in reality, there are stochastic factors. Stochasticity refers to the variability in the system involving those factors that are affecting or influencing population growth. Stochasticity might be related to good years and bad years for population growth.

In real situations, the compliance of the whole assumption does not occur. The previously mentioned constants might vary, constantly changing the interaction between the predator and the prey. These parameters change in different degrees, resulting in varying circumstances for both species.

3 0
3 years ago
Peripheral adaptation ________ the number of action potentials that reach the cns.
irga5000 [103]
The answer would be decreases.

hope this helped :)
3 0
3 years ago
Other questions:
  • The Weaver birds from the African savanna exhibit a trade-off between risking starvation and being hunted by predators. As a res
    9·2 answers
  • Multicellular organisms _____ genetic information and mix the information from both parents
    13·1 answer
  • Which type of spectroscopy would you most likely use to determine the composition of the moon through a telescope
    6·1 answer
  • The lithosphere is part of earth's what?
    6·1 answer
  • One theory of dreaming says that the brain _____, or puts together, an explanation of the cortex activation from memories and ot
    13·1 answer
  • Mr. Krabs created a secret ingredient for a breath mint that he thinks will “cure” the bad breath people get from eating crabby
    12·2 answers
  • What is the basic unit of matter?
    5·2 answers
  • A researcher speculates that an enzyme has the following energy profile and that it is a reasonable profile given what we know a
    12·1 answer
  • The bacteria cell cycle does not have an analogous phase to the eukaryotic phase G2. The reason for this is that _____.
    7·1 answer
  • Why do some flowers have so many pollen grains and ovules?
    9·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!