Unit 4 post class assignment questions Flashcards
The internal environment of multicellular animals is influenced mostly by their external environment and:
the activities of other cells in the body.
Which of the following is not a way that animals gain water?
as a by-product of photosynthesis
Which of the following phrases best describes homeostasis?
keeping important internal parameters relatively constant
Which of the following is a method animals have for facilitating heat loss to the environment?
increasing bloodflow to the skin
The human body’s temperature regulator is located in the:
brain
Which of the following conditions is most likely to directly cause hypothermia?
exposure to very cold and wet weather
When you cut yourself and begin to bleed, injured tissue releases chemicals that activate the blood-clotting process. Once activated, cell fragments called platelets then activate other platelets, in turn, leading to a rapid formation of a blood clot. In this physiological example, the rapid increase in the blood-clotting reaction caused by already activated platelets can be called a:
positive feedback system.
Extreme hyperthermia is referred to as _____________ and can lead to problems in the normal functioning of the body.
heat stroke
Your body sweats in hot weather, but stops sweating when you enter an air-conditioned building. The cessation of sweating as the body becomes cooler is an example of:
negative feedback.
Why is the adaptive immune system slower to respond to a pathogen compared to the innate immune system?
The adaptive immune system has to synthesize large numbers of specialized proteins, whereas the innate immune system is ready to go.
The inflammatory response results in redness and heat in the inflamed area. This is due to:
increased blood flow into the area.
How is your body able to make large amounts of specific antibodies against an invading pathogen?
The foreign antigen binds to a particular B cell, which divides to make an army of B (plasma) cells that all produce large amounts of the same specific antibody.
Which statement about antibody molecules is true?
Phagocytes can more easily ingest a pathogen coated with antibodies.
Pathogens are:
disease-causing microorganisms.
The secondary immune response occurs much more quickly than the primary response because:
memory cells made in the primary response are poised and ready in the secondary response.
What role do cytokines play in the innate immune system?
alerting other cells that a pathogen is present
An antigen can be defined as:
a molecule that induces a specific immune response.
Which of the following is a true statement?
The various molecules on the surface of a bacterium can all be antigens.
What is the effect of histamine?
localized dilation (widening) of blood vessels
When was the Ebola vaccine created?
2003
Which of the following must happen before a vaccine can be used on the public?
animal testing, trials for effectiveness in generating immunity, safety trials in humans
What is CEPI funding?
vaccine development
CEPI is focusing on which of the following diseases for the next 5 years?
Lassa Fever, MERS, Nipah
Where have Nipah outbreaks occurred?
Malaysia
Does the rVSV vaccine work against all Ebola strains?
no
Does the rVSV vaccine contain the Ebola virus?
no
A new class of vaccines is being developed that would use a person’s cells to make the viral protein. They work by delivering ___ into the person.
DNA
A friend wants to take a trip to an area of the world where it is very dry and the temperature varies with the seasons. Which biome would fit that description?
desert
The ecosystem of a given area consists of which of these?
all the living organisms and non-living materials
The two essential features of ecosystems are:
the biotic and abiotic environments.
Which phrase best defines a biome?
areas with distinct plant communities and associated with particular climates
Which statement best explains why the temperatures at the equator are warmer than at the North Pole?
The sun shines most directly on the equator and spreads out over a relatively small area.
A rain shadow effect occurs:
when wind from the ocean passes over a coastal mountain to the other side.
A driving force behind ocean currents is:
global wind circulation.
Why are many deserts located on the backside of mountains?
Moist air masses are forced to rise over mountains and lose their moisture in the process, which results in very little moisture availability for the other side of the mountain.
El Niño:
causes western Pacific Ocean weather systems to shift to the eastern Pacific Ocean.
Which of the following is not a part of an organism’s habitat?
living organisms in the area
A population:
is a group of coexisting organisms that are capable of interbreeding.
If r = .20 for a population at a given time (t) when N = 500, what will the population size be at time t + 2 (two generations later) if the population keeps growing at the same rate?
720
The purpose of a population model is to:
predict or explain changes in an organism’s abundance from one generation to the next.
What type of survivorship curve do humans have?
type 1
A population pyramid:
reflects the number of individuals in various age groups in a population.
Which of the following represents the per capita growth rate of a population?
r
Disease is spread more quickly between individuals who live in close proximity, such as in a nesting colony of penguins. Disease can be considered a(n):
density-dependent factor.
In a population, as N approaches K, the logistic growth equation predicts that:
the growth rate will approach zero.
Which description represents an irreversible disturbance?
extinction of the Chinese river dolphin
In the United States, purple loosestrife is a(n):
exotic flowering plant that has caused significant problems for native species.
Which of these is an indirect effect of acid rain?
the loss of calcium and potassium ions from the soil
_______________ is responsible for the greatest loss of tropical forests.
Agriculture
Ozone depletion allows ____________ to reach the earth’s surface.
short-wavelength ultraviolet light
Biodiversity _________________ have been identified based on high biodiversity and imminent threats caused by human activities.
hotspots
__________ is currently the leading cause of extinction.
Habitat loss
When sulfur burns, its immediate product is:
the gas sulfur dioxide (SO2).
Introduced species frequently cause more damage to island ecosystems than to mainland ecosystems. All of these are reasonable explanations for this except:
introduced species have better dispersal capabilities than endemic species.
Biodiversity has extrinsic value as well as __________ value, independent of its utilitarian value to humans.
intrinsic
