Answer:
The correct answer is- C. double or single-stranded DNA or double or single-stranded RNA.
Explanation:
All the viruses are intracellular parasites which means they obtain their nutrition from their host. Viruses do not have cellular level of organization. They only have their nucleic acid which is surrounded by a protein coat called a capsid.
The nucleic acid in viruses can be of different types. It can be single or double-stranded DNA or single or double-stranded RNA. Their genome can be linear or circular. They inject their genetic material in their host and introduce it in the host genome. Therefore the correct answer is C.
Answer:
The correct answer is: <em>C. Increased average lifespan to 78 in the US.</em>
Explanation:
Science has impacted human health by increasing the average lifespan to 78 in the US. Over the last couple of decades, the life expectancy of Americans has increased significantly than what it was 200 years ago. This can be attributed to:
1. Vaccinations- Since the invention of vaccinations, diseases such as tuberculosis, cholera and polio which were major causes of death 200 years ago have virtually been eradicated in the US.
2. Abundant and safer foods available- Commercial and large scale farming has made a wide variety of nutritious foods easier to obtain.
3. Improved sanitation- Safer drinking water, sewage treatment and stricter food inspection has significantly reduced the rate of illnesses due to poor hygiene and sanitation.
In these ways, science has impacted human health by increasing the average lifespan to 78 in the US.
Answer:
1) A chemical reaction is shown.
SnO2 + H2 → Sn + H2O
What is true about this chemical reaction?
B.
It is unbalanced because the mass of the reactants (number of atoms) is greater than the mass of the products (number of atoms).
2) Read the information about an experiment.
Jadon plans on carrying out an experiment involving the burning of steel wool to illustrate the conservation of mass. Steel wool is made of iron. When it is burned it combines with oxygen to form iron(III) oxide.
Which step in his experiment is the most important if he wants his experiment to correctly demonstrate the conservation of mass?
A.
The steel wool should be burned inside of a sealed jar or other closed system.
Explanation:
The explanation to number 1 is that I selected it in my test and got it.
The explanation the number 2 is from the link below:
https://quizizz.com/admin/quiz/5dee60258f1145001bc02ed5/physical-science-2nd-9-weeks-practice-test-2020
