Biology Test #3

HALLOWEEN

Energy

The potential to do work.

Work

Physical activity/motion.

Photosynthesis

The biochemical process responsible for converting electromagnetic energy from the sun into chemical energy inside molecules.

Why is energy needed by individual organisms on a cellular level?

Cells need to respirate, grow, maintain themselves, & move.

Cite the percentages for how much energy is used for cellular respiration, growth, & how much is lost as feces/heat, use a caterpillar as an example.

50% lost as feces/heat

33% lost through cellular respiration

16.5% for growth/repair

List and define the 2 laws that state how energy behaves.

1st Law of Thermodynamics: energy cannot be created nor destroyed, but it can be transformed and transferred

2nd Law of Thermodynamics: when energy is transformed or transferred, some is converted as heat

What is a food web? Why is it different than a food chain?

A food a system of interlocking and interdependent food chains.

Why are decomposers important for nutrient cycling in an ecosystem?

Decomposers break apart detritis into simpler inorganic materials, making nutrients available to primary producers.

Highest NPP

Tropical rainforests

Swamps/lakes

Algal beds

Lowest NPP

Deserts

Tundra

Open ocean

What are the abiotic factors than can affect the GPP in an area?

Sunlight

Precipitation

Temperture

Why do phytoplankton have a higher NPP compared to trees?

Phytoplankton have a higher NPP than trees because trees respirate more, using the energy.

What is biomass?

Renewable dry organic mass from organisms.

Which trophic level has the most biomass?

Lower trophic level/primary

(because of there being more animals)

3 properties that toxins must have in order to biomagnify.

Fat solubility, persistence, & mobile

Why do fat soluble compounds bioaccumulate?

Those compounds don’t get excreted easily through urine.

Which trophic level usually has the highest level of biomagnifying toxins?

Quantitary

How has DDT affected raptor populations?

How has the US tried to reverse the effects on raptors?

DDT has made it harder for raptors to produce the calcium they need for their eggs shells, meaning their reproduction rate goes down.

The US banned DDT to help fix this.

Gross primary production (GPP)

The rate of photosynthesis occurring in an area.

(how fast organic molecules are produced, glucose)

Net primary production (NPP)

The rate at which organic compounds are stored in the tissues of producers

(rate of growth of producers tissue)

How is GPP and NPP different?

GPP has the total amount of energy while NPP is what is really used.

GPP is the total rate at which material is produced and NPP is the rate at which material is accumulated in excess of respiration.

GPP - respiration = NPP

Bioaccumulation

An increase in the concentration of a chemical in a biological organism over time, compared to the chemical's concentration in the environment

Biomagnification

The concentration of toxins in an organism as a result of ingesting other plants or animals in which have the toxins.

Which trophic level usually takes in toxins first from the environment?

Why would toxins biomagnify?

Producers.

The toxins stay in the organisms and get passed up the food web.