Essentially, a control variable is what is kept the same throughout the experiment, and it is not of primary concern in the experimental outcome. Any change in a control variable in an experiment would invalidate the correlation of dependent variables (DV) to the independent variable (IV), thus skewing the results.
 
        
             
        
        
        
Recall the endosymbiosis hypothesis and recall endosymbiosis. Remember that the very first cell was a prokaryotic cell. Which engulfed chloroplast precursors and mitochondria. We all come from these cells. And how we evolved over time shows the relationship. I'm a bio major hope I helped
        
             
        
        
        
Answer:toxic
Explanation:
A ureotelic organism excretes excess nitrogen as urea. Urea is less toxic and needs less water in comparison to Ammonia. Ureotelic organisms include cartilaginous fish, few bony fishes, adult amphibians and mammals including humans. The uricotelic organism excretes uric acid or its salts
 
        
             
        
        
        
The organs represented in the image are the Brain, nerve, and spinal cords that monitor and react to changes in the body and its environment. 
<h3>What are Organs?</h3>
Organs may be defined as an assemblage of tissues that structurally construct an operational unit specialized to accomplish a distinct operation and functions in the body of a living organism. 
The nerves function in sending and receiving signals to the brain from external stimuli. They give the perception of feeling pain, relaxation, stress, etc to the brain according to the situations. 
The complete question is as follows:
The picture shows an organ system in the human body.
Brain, Nerve, and spinal cord. 
What do these organs do in the human body?
- They filter pathogens and dead cells out of lymph before it returns to the blood.
- They monitor and react to changes in the body and its environment.
- They release hormones that control the activities of cells and organs.
- They identify and destroy things that are foreign or harmful to the body. 
Therefore, the correct option for this question is B, i.e. They monitor and react to changes in the body and its environment. 
To learn more about Organs, refer to the link:
brainly.com/question/1126526
#SPJ1
 
        
             
        
        
        
Answer:
<u>Starch</u> is the storage form of glucose (energy) in plants and the glucose molecules are linked by alpha 1,4 glycosidic linkage.
<u>Cellulose </u>is a structural component of the plant cell wall and glucose molecules are linked by beta 1,4 glycosidic linkage.
<u>Glycogen</u> is the storage form of glucose (energy) in animals and glucose molecules are linked by alpha 1,6 glycosidic linkage.
Explanation:
All of these sugars are polysaccaride sugars containing large number of glucose subunits.
Starch is a polysaccharide extracted from agricultural raw materials. It contains amylose and amylopectin. Amylose is an un-branched chain polymer of D-glucose units while amylopectin is a branched chain polymer of D-glucose units.
Glycogen is the storage form of glucose in animals, It is stored in muscles and liver and it is a branched polysaccaride. 
Cellulose is the storage form of glucose in plants and leaves.