Biology Exam 3

Which of the following is only true of RNA, but not DNA

Adenine pairs with uracil

Which of the following is a characteristic of all living things

All living things maintain a constant internal environment

As global temperatures increase, which of the following scenarios is most likely to happen?

Glaciers and snow coverage decrease

How do greenhouse gases cause climate warming?

Greenhouse gases prevent radiation of infrared energy back into space, trapping the heat near the earth's surface and causing the climate to warm

Carbon sinks are reservoirs that hold large amounts of carbon. Which of the following are considered to be carbon sinks?

Oceans, fossil fuels deep underground, and the atmosphere

Which of the following is/are true about natural selection?

On average, it favors the survival of individuals that have adaptive characteristics

Why are new flu vaccinations required for each new flu season?

The flu virus mutates frequently enough that last year's vaccination will no longer target currently circulating flu strains

Which statement below best summarizes the overall purpose of the light-dependent reactions?

The light-dependent reactions capture the energy from the sun and transfer it to high-energy molecules

How does climate change affect earth's oceans?

The pH level of the ocean will shift to a more acidic environment, leading to stress and the possible extinction of many species of shellfish and corals

What do all greenhouse gases have in common?

They have complex structures that allow them to contribute to the greenhouse effect by trapping heat energy

Giant viruses are challenging the historical notion that viruses are nonliving things. What characteristic do giant viruses possess that make scientists think twice about their classification?

They have the ability to manufacture their own proteins without the help of a host cell

All viruses are made up of two components. What are they?

a protein capsid and genetic material, in the form of either RNA or DNA

______ is any substance that produces a specific immune response by the body. Antigens are usually proteins or large carbohydrates that are specific to pathogens such as bacteria and viruses

antigen

Occurs when there are small changes in the surface spikes of the influenza virus. This is an example of _____

antigenic drift

When two different forms of a virus infect the same cell, the host cell may manufacture viral particles from both viruses to reassemble them into a new form of virus. This process is called _____

antigenic shift

The activities of macrophages

are part of the nonspecific response against disease and stimulate phagocytic neutrophils

What is the correct sequence of events in viral reproduction?

attachment, penetration, biosynthesis, maturation and release

Because fossil fuels are the remains of once living organisms, they contain reservoirs of _____ that are released into the atmosphere when they are burned

carbon

Which of these is the best description of a virus?

chemical complexes of RNA or DNA protected by a protein shell

Research for a universal flu vaccine tends to focus on

core proteins, as they do not mutate as rapidly as H and N spikes and they tend to be similar between different influenza strains

Which of the following types of cells would a flu virus most likely target as the means of entry into the body?

epithelial cells lining the respiratory system

Which process best describes how viruses may originate in animals and eventually be transmitted to humans, causing outbreaks

evolution

Getting a flu vaccine guarantees individuals will not get the flu

false

Antigens are

foreign molecules that bind to white blood cells through specialized receptors, leading to the proliferation of lymphocytes

A product of photosynthesis, _____ is a carbon-based molecule that is the chief source of energy for most organisms

glucose

Which of the following is the most likely cause for the sudden sharp increase in atmospheric carbon dioxide levels?

human activities, including the use of fossil fuels, changes in agricultural practices, and deforestation

Over the past several decades, the overall trend for earth's temperatures has been

increases in overall global temperatures at an accelerating rate, a phenomenon known as global warming

The greenhouse effect

is caused by gases such as carbon dioxide trapping heat in the earth's atmosphere

The cycle of viral infection that will rapidly result in the death of a bacterial cell is called the _____ cycle

lytic

Which of the following are greenhouse gases?

methane and carbon dioxide

Which of the following acts as a carbon source within the carbon cycle?

respiration from humans and animals

Climate can best be described as

the average weather patterns in a given area over long periods of time

In the _____ cycle, following penetration into the cell, the viral DNA integrates into the host cell's DNA. the virus remains inactive (or latent)

lysogenic

The light reactions of photosynthesis occur within the _____ of the chloroplast and the Calvin Cycle reactions occur within the _____ of the chloroplast

thylakoid; stroma

_____ act as an alarm to the organ systems of the body, alerting them that a pathogen is present

Cytokines