Evolution Exam Review

Evolution is currently a theory. What is the definition of a theory?

• A proposed explanation of a natural phenomenon supported by evidence gathered using scientific methods.

What is the name of Darwin’s book on evolution?

• On the Origin of Species

Homologous Structures

• Structures that are similar in evolutionary origin, but have different purposes (ex. similar limb bones in vertebrates)

Vestigial Structures

• Structures that served an important purpose in our ancestors but do not have that purpose today

Where did Darwin study finches and tortoises?

• the Galapagos Islands

What mechanism did Darwin propose for evolution?

• Natural selection

Define natural selection

• Survival and reproduction of organisms that are genetically best adapted to their environment due to favorable traits

What is an example of biochemical evidence for evolution?

• Similarities in DNA sequences

Pig A 500 lbs, 6 piglets Pig B 600 lbs 12 pigletsPig C 400 lbs 8 piglets Which pig is most fit?

• Pig B

Natural selection acts on ___________ and mutations act on __________.

• Populations, (species)• DNA, (genes)

List 6 evidences for evolution• Fossils• Homologous structures• Geographic distribution of living things• Vestigial structures• Comparative embryology• Biochemistry (conserved DNA sequences)

Define fitness

• The ability of an organism to reproduce and have viable offspring

Ecology Review Chapter 3

Food Chain!

Ecology

Study of the interactions that take place between organisms and organisms and their environment.

Biotic

Living parts of the environment: plants, animals & microorganisms

Abiotic

Non-living parts of the environment: water, air, light, rocks, temperature, soil

Levels of Organization in Ecology

• A species includes only one type of organism. – Example: pigeon

• A population includes all members of one species that live in the same area. – Example: all the pigeons in Houston

• A community includes all of the different species that live in the same area. – Example: all the pigeons, ants, oak trees, dogs,

etc. that live in Houston

Levels, continued…

• An ecosystem includes both the community and the abiotic factors. – Example: the Houston community plus

the cars, buildings, rocks, air…• A biome is a large area of land or water

that has the same climate, land characteristics, flora and fauna.

-- Example: desert, tundra, taiga, savannah

• The biosphere is all the parts of the Earth that can support life: the air, the water and the land.

Produce or Consume

1. Producer (autotroph)–can make its

own food – forms the

base of the food web

Mmmmm…delicious

2. Consumer (heterotroph)– cannot make its own food

There are several words that describe consumers…– Prey: the hunted– Predator: the hunter– Herbivore: eats plants– Carnivore: eats animals– Omnivore: eats both plants and animals

Adaptations of consumers:Carnivore - meat-eating animal with sharp canine teeth specialized to rip and tear flesh Herbivore - plant-eating animal with incisors specialized to cut vegetation and large, flat molars to grind it Omnivore - plant- and meat-eating animal with incisors specialized to cut vegetables, premolars to chew meat, and molars to grind food

Ewwww, gross

3. Decomposer– Breaks down dead organisms– Examples: bacteria, fungi, worms– Complete the circle of life by returning

nutrients to the soil

• Food chain - chain of organisms along which energy, in the form of food, passes. An organism feeds on the link before it and is in turn prey for the link after it. Arrows show the direction of energy flow.

• Food web - Complex network of many interconnected food chains and feeding relationships

Food Chain

Food Web

Energy Pyramids show that there is more energy available in the producers of an ecosystem than the consumers. The least amount of energy is available in the bodies of the animals at the top of the food chain. Most of the energy is used by the organisms and lost as heat.

___________ carry out many of the important steps of the nitrogen cycle.

A. BacteriaB. FixationsC. NitrificationsD. Atmospheres

Answer: A

Plants Aphids Spiders Sparrows

In this food chain, the spiders are----A. ProducersB. Primary consumersC. CompetitorsD. Secondary consumers

Answer: D

In the food web above, which are primary consumers?

A. Tree and grassB. Deer, grasshopper, and rabbitC. Owl, fox, and wolfD. Bird and snake

Answer: B

In the food web above, which are secondary consumers?

A. Tree and grassB. Deer, grasshopper, and rabbitC. Owl, fox, and wolfD. Bird and snake

Answer: D

According to the biomass pyramid below, what is the mass of the autotrophs?

A.6g

B.70g

C.275g

D.450g

Answer: D

Which of these pictures best represents commensalism?

Answer: D

___________ carry out many of the important steps of the nitrogen cycle.

A. BacteriaB. FixationsC. NitrificationsD. Atmospheres

Answer: A

The process in which a plant makes food from water and carbon dioxide, using energy from the sun is known as_______________.

A.Respiration

B.Absorption

C.Reproduction

D.Photosynthesis

Answer: D

Which of the following is most likely to cause increases in a predator population?A. fewer preyB. A reduction in competitionC. More parasitesD. A period of drought

Answer: B

Plants Aphids Spiders Sparrows

In this food chain, the aphids are----A. ProducersB. Primary consumersC. CompetitorsD. Secondary consumers

Answer: B

In Central America there is a tree called bullhorn acacia (Acacia cornigera) that provides both food and shelter to a certain species of ant (pseudomyrmex ferruginea). The ants live within the tree without causing harm. In fact the ants protect the tree by vigorously attacking and stinging other animals that try to eat it.

This relationship is an example of---

A.Predation

B.Parasitism

C.Mutualism

D.commensalism

Answer: C

The carbon cycle, nitrogen cycle, and water cycle are all part of

A. The rock cycleB. The energy pyramidC. The nutrient cycleD. autotrophs

Answer: C

Termites have protozoa living inside their digestive system. The protozoa digest the wood that the termites consume. How would you characterize the relationship between the termite and the protozoa?

A. ParasiticB. CommensalC. MutualD. protocooperative

Answer: C

How could the amount of CO2 in the atmosphere be decreased?

A. Increase the number of plantsB. Decrease the number of plantsC. Burn more fossil fuelsD. Increase the number of animals

Answer: A