There are several factors that virologists use to classify viruses. Some of these factors include i) type of nucleic acid; ii) presence of an envelope; iii) size and shape of the virus; iv) morphology of the capsid; and v) how the virus reproduces. Lauren, a seasoned animal virologist, has started researching bacteriophages, viruses that are able to infect bacteria. While growing bacteria in the lab, Lauren notices that her samples are not growing properly. She thinks that she may have contaminated her bacterial cultures accidentally. Lauren thinks back through the process of adding the bacteria to the media--perhaps she used a flask that had not been cleaned properly, or the media were contaminated prior to use. The first thing Lauren does is visualize her culture underneath the electron microscope, a microscope powerful enough to magnify the bacteriophage if present. As soon as Lauren begins her microscopy, she notices a small organism that looks like it has a head and legs! Lauren then starts the journey of classifying this virus by recording her observations.

Think about the many factors that are used to classify viruses. In order for Lauren to determine the type of virus she may have, she needs to understand some basic concepts about how viruses are characterized.

Correct Statements

Viruses are not capable of metabolic activity on their own; they must have a host cell to reproduce.

The genetic material of a virus can be DNA or RNA.

Viruses can have different shapes.

Capsids function to surround and protect the nucleic acid core.

The genomes of viruses are usually smaller than the genomes of bacteria.

Incorrect Statements

All viruses have both a capsid and an envelope.

Capsids are adquired from the host cell during replication or release.

The intracellular state of a virus is called a virion.

Explanation:

both anaerobic and aerobic respiration use glucose (or other carbohydrates), proteins and lipids to produce atp and nadh. cell uses those energy molecules, obtained from food and   breaks them down during the chemical reactions of respiration. in anaerobic respiration, nadh is regenerated to nad+ by enzymes lactate dehydrogenase (lactate is produced, e.g. in muscle cells) or by alcohol dehydrogenase where ethanol is produced (alcohol fermentation), while in aerobic respiration, electrons from nadh are deposited in the mitochondria to regenerate nad+ (electron transport chain. anaerobic respiration produces 2 atp per molecule of glucose compared to aerobic respiration where about 38 atp molecules are produced.

succession returns a disturbed

ecosystem to a more stable state. this is also classified into two (2) types:

primary succession and secondary succession. the primary succession arises when

a new land is transformed and a bare rock has been exposed providing an environment

that can be occupied for the first time. while, secondary succession occurs

when a previously occupied environment was disturbed that kills much of all its

community

explanation: