Answer:
The correct answer is -
the independent variable - if fertilizer added or not,
the dependant variable - the height of the plant and
the standardized variable - 200ml water
Explanation:
In this study, the student wanted to see the effect of the fertilizer on the growth of the plant so the independent variable is the treatment of the fertilizer as manipulated or the independent variable is the factor which is affected or changed purposely during an experiment while other variables remain constant.
The dependent variable is the factor that is based or depends on the independent variable and measured to see the effect which is the height of the plants in this case.
The standardized or the control variable is the variable that remains constant throughout the experiment, 200 ml water treatment is the control variable in this experiment.
Answer:
The number of STR repeats is unique and therefore it is considered as an allele of that <em>locus</em>
Explanation:
Short Tandem Repeats (STRs), also known as microsatellites or simple sequence repeats (SSRs), are short DNA sequences with a size of 1-6 nucleotide bases which may be many times repeated in tandem. STRs localize in specific regions of the genome (<em>loci</em>) and therefore they are molecular markers. Gel electrophoresis a technique used to separate DNA fragments based on their size. In consequence, the pattern of STR repeats or 'alleles' obtained by electrophoresis can be used to identify individuals. In a gel electrophoresis, STR markers produce different bands that run more slowly or faster on the gel in different lanes according to their size (e.g., more slowly >> higher size of the STR sequence), and thereby STR alleles are unique and serve to identify individuals.
Answer:
The freshwater trout requires a lower salt ions to function.
Explanation:
Answer:
Unlike typical mammalian red blood cells, those from amphibians, such as frogs, contain a DNA-bearing nucleus that is visible in the center of the cell. The circulatory system of amphibians is rather unusual, their hearts having three chambers, two atria, and a single ventricle.
NegativePositive
Positive
The design of the amphibian circulatory system is curious because blood accumulates oxygen in the lungs and is then returned to the heart before being pumped into the rest of the circulatory system. Therefore, a mixing between oxygenated and deoxygenated blood occurs as blood returning to the heart from the lungs is mixed with incoming blood from the body. Frogs handle this situation by having a very slow metabolism and by absorbing some oxygen through their skin. In addition, the ventricle does have some directional control over the distribution of the blood.
Negative
The presence of a nucleus in amphibian red blood cells allows researchers easy access to large quantities of amphibian DNA. Frog blood has both a solid and a liquid portion. The liquid plasma carries solid elements such as red and white blood cells. Blood can be collected from frogs and the red blood cells isolated by centrifugation. After removal of the residual plasma, purified cells can be treated with specific enzymes and detergents to digest the cellular envelope and release DNA from its protein complex. The DNA is then useful for scientific studies and experiments.
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Explanation:
Answer:
increase anxiety; decreased vulnerability to overreact to stress
Explanation:
Serotonin (5-HT) is a natural neurotransmitter that carries signals between nerve cells (neurons) throughout the body. This neurotransmitter (serotonin) is responsible for regulating many biological functions (e.g., mood, digestion, sleep, etc). Moreover, it has been shown that there is an association between low cerebrospinal fluid 5-hydroxyindole-acetic acid (5-HIAA, the principal serotonin metabolite in the brain) levels and the risk of developing depression or destructive behaviors. In addition, serotonin concentration can also be elevated in situations of anxiety and/or stress. Antidepressants such as Prozac, Zoloft and Paxil act as serotonin uptake inhibitors that increase serotonin concentration at the synaptic site. Like other drugs, these antidepressants may lead to increase anxiety and decrease the vulnerability to react to stress by downregulating sensitivity to serotonin released during natural stress situations.
