Answer:
A factor that is purposely left the same.
Explanation:
A controlled variable should not be changed throughout an experiment or else it will affect the outcome of each individual trial.
Answer:
During capillary exchange , red blood cells are the substance that is not sent out to the tissue.
Explanation:
Capillaries have thin walled cell which can only exchange glucose which is a monosaccharide, water molecule, carbondioxide and oxygen gas. These substances are exchanged because they are small in size while red blood cells are not exchanged due to large in size.
Answer:
A) & B)
Explanation:
A) There are certain viruses that are present in both healthy and disease people.
Example: Polio virus is found in many human but it causes disesease in only 1% of human.
B) Viruses require host machinery for replication so they may not replicate in pure culture.
The postulate C is also violated, the virus may not produce disease in non-human experimental host because of inappropriate animal or vaccinated animal etc. Others exception includes, the same disease may be caused by various organisms and different organisms can also cause the same disease.
<u>Answer</u>: A food web is a graphical representation of interconnected food chains.
A desert food web will have as producers the cacti, annual flowers and sagebrush. Some of the primary consumers of these food web are the ants, lizards and pronghorn.
Secondary consumers are the scorpions, snakes and wolves. The haws represent tertiary consumers and in some instances they may even eat wolves, especially unprotected cubs.
The energy flows through the food web from inorganic components such as the sun, nutrients, water into the producers. Then primary consumers eat the producers and are in turn eaten by the secondary consumers. The tertiary consumers will feed on both primary and secondary consumers.
<u>Notes</u>:
Please find attached all the necessary files with the exception of the desert flowers (due to maximum numbers of attached files restriction). These images are not copywrighted and thus free to use.
I have created the required table as an Excell document in case you need to modify it. I did not add the images for the species in the Excell table.
I have also created a more exensive food web (described in the Answer section) for your desert habitat.
As I had some difficulties in understanding the last part of your question, please let me know in a comment if you require additional modifications. I have saved the foodweb PSD file as well as he Excell file.
The difference between gram positive and gram negative is the stuctural difference in the cell walls