Biology Exam #2

The half life of an isotope is 5,000 years. With a starting material of 1g of an isotope, after 5,000 years, how much would remain?

.5 g half life= amount of time a material will take to decay by half

How old is the Earth?

4-5 billion years old

All of the following are true of algae, Except A. They are plants B. Some are single celled C. They are autotrophs D. Some are multi-celled

A. They are plants

Explain why adaptive radiation often occurs after mass extinctions

Adaptive radiation is a process of radiation when animals adapt to different modes of life (running, leaping, flying, swimming, and climbing). When a mass extinction occurs the biodiversity of earth is significantly lower since so many animals were killed. This leaves the remaining organisms free to change their modes of life.

What is the purpose of bacterial endospores?

Allow bacterium to survive extended periods of heat or dryness Endospores= meant to get bacterium through environments of high stress

What organisms are thought to be the first cells to appear on earth?

Archaea Archaea are single cell microorganisms, were originally classified as bacteria

Carnivorous plants like the Venus fly trap that eat insects are

Autotrophs Autotrophs are able to form nutritional organic substances from single inorganic substances such as carbon dioxide

Look at #1 on Exam

B. around 9 billion years and 4.5 billion years, respectively Draw lines from the left side of the graph to the curve

The microbial symbiotic partner of the hydrothermal vent dwelling red plumed tube worm most likely would use which of the following for its source of carbon?

CO2

You perform a catalase test on a sample and find absolutely NO bubbling. What can you conclude about the organism being able to survive on a bed rail in a hospital?

Cannot survive This is because no bubbles were produced from the test

Dictyostelium discoideum is a __________ that has a complex life cycle between single celled and multi-celled states involving the formation of a slug and ultimately the formation of a survival spore when nutrients become scarce

Cellular slime mold

Most of Earth's biosphere is?

Cold

You are a scientist who notices great similarities between the spines of a hedgehog and the spines of a porcupine. When you study their genetics, however, you notice that the set of genes that code for hedgehog spines is a different set of genes than the set that codes for porcupine spines. You decide this must be an example of __________

Convergent evolution Convergent evolution is the process by which unrelated organisms evolve similar body forms, correlations, and adaptions

Which is NOT true of prokaryotes? A. They are found on you B. They are found in you C. They are most likely the first colonizers of of Earth D. They are exclusive to land

D. They are exclusive to land Prokaryotes include bacteria and cyanobacteria, they are single celled organisms (very simple)

List in order from earliest from most recent land plants Great Oxidation Event first prokaryotes first multi-cellular eukaryotes Tiktaalik

First prokaryotes Great Oxidation Event First multi-cellular eukaryotes Land plants Tiktaalik

Look at #42 on test

Gorillas This is because the organism before strayed off due to an evolution already

Pine trees, redwoods, and confiners with open seed cones belong in which plant group?

Gymnosperms Gymnosperms are plants/trees that have seeds unprotected by an ovary or fruit

The endosymbiotic theory explains

How mitochondria and chloroplasts originated from free-living cells Endosymbiotic Theory= attempts to explain the origins of eukaryotic cell organelles such as mitochondria

Why is Tiktaalik considered as a transitional fossil?

Its a hybrid of an aquatic and terrestrial vertebrate Its considered to be the first to transition from fish to amphibian

In Darwins famous experiment with sundew plants, which food source(s) did the plants NOT react to?

Paper

Another term for the structure of the branching tree that depicts evolutionary relationships is

Phylogeny Phylogenetics is the study of evolutionary history and relationships

If you explore the life inside a hydrothermal vent, you will likely find a ____________ cell, which is a member of domain __________

Prokaryotic, Archaea Hydro vents are extremely hot, have extremely high pressure, and have anaerobic conditions

Amoebas use _________ for movement

Pseudopodia

Refrigeration does not always stop food decomposition because ________ organisms are capable of growth at these temperatures

Psychrophilic organisms that are capable of growth and reproduce in low temps

Explain a biological for why your Valentine's date likely dumped you when you gave your date a Titan Arum, the largest flower in the world. To which group of plant swould this organism belong?

The Titan Arum carries a rotting corpse smell. It may be an angiosperm

Explain the mechanism and the purpose of two feeding checkpoints the Venus fly trap uses to save energy?

The Venus fly trap uses senetive hairs on the plants head. Once the hair is triggered it stores that energy and wait for a second trigger.

An alien race exploring the now barren planet Earth in the distant future found a fossil embedded in rock as shown in the picture below. What do you estimate is the age of the fossil? Explain what (human derrived) method aliens likely used to estimate this fossils age?

The fossil is about 285 mya. The alien used Relative Dating to find the age of the fossil. Relative Dating is when the age of the rocks are placed in order from older to younger.

Explain two reasons why some parts of the planet are rich in fossils, and in other places there are no, or few, fossils?

The fossils must be buried quickly by surrounding rocks and such, then fossil continues to be buried by more rocks. This creates pressure and ultimately creates the mold of the fossil. Some areas in the world just cannot support that Also, in the past some areas of the Earth were not inhabited by animals

What do all members of the informal group known as protists have in common?

They are all eukaryotic Protists is any eukaryotic organism that has cells with nuclei and its not an animal, plant, or fungus

What type of microscope would be best for studying the detailed image of a chloroplast in a bacteria cell?

Transmission electron microscope (TEM) Transmission= 2D projections of inner structure Scanning= 3D image of surface

A structure inherited from an ancestor that no longer serves a clear purpose in an organism is called a

Vestigal Structure (i.e wisdom teeth)

You are walking through the Smokies, spending the morning in a creek environment in Cades Cove, and by the afternoon you have entered a drier forest as you make your way up to the top of Clingman's Dome (highest mountain peek in the Smokies and a drier climate) Which of the following describes the changes in species composition you would expect?

You see more bryophytes in Cades Cove but don't find many of them in Clingmans dome bryophytes prefer moist enviornments (i.e moss)

Plants get their carbon from

air

The similarity between the forearm of a human and an alligator suggests that

alligators and humans share a common ancestor

Animal fossils usually have these structures

bony skeletons or hard shells

Which best describes plant groups in order of terrestrial adaptions from earliest to the most recent?

bryophytes, ferns, gymnosperms, and angiosperms Bryophytes= Simple, like moist climates (i.e moss) Ferns= reproduce via spores, have no seeds nor flowers Gymnosperms= plants/trees that have unprotected seeds Angiosperms= has flowers, produce seeds enclosed with protection (Ferns, Gymnosperms, and Angiosperms all are vascular plants) - They have conducting tissue that they use to transport nutrients and water

In the Miller Urey experience what happened to the carbon?

created organic compounds and amino acids

Nitrogen fixer

diazotroph

Which would not be considered a trace fossil?

dinosaur skeleton Trace fossil is anything left behind by the animal besides the skeleton (i.e footprint)

Organisms are placed into one of three domains of life on the basis of

evolutionary history as assessed by genetic relatedness Archaea= Prokaryote, live in more extreme enviornments than bacteria, are not senestive to antibiotics that affect bacteria Bacteria= Prokaryote, Has Peptidoglycan, Snestive to traditional antibiotic Eukarya= Eukaryotic, has different kingdoms under it, resistant to antibotics that affect bacteria, no Peptidoglycan

The presence of a membrane-bound organelles in a cell tell you that the cell must be

from a member of the domain Eukarya membrane bound means the organelles is in a organized and specialized structure within the cell

Structures that have the same evolutionary origin even though they may now have different structures of functions are said to be

homologous Birds also have similar bones in their wings as we do in our hands and wrist

Look at #9

monotrichous bacillius

What is the function of flagella?

motility Motility is the ability for an object to move independently

This gas began to accumulate between 3 and 2.5 billion years ago

oxygen

What term refers to the fine hair like bristles that aid in adhesion in prokaryotic organisms?

pili They sometimes use it to adhere to the organism to trigger them to be eaten and then live in the host cell

An organism that is eukaryotic and photosynthetic is a

plant or protist They are both Eukaryotic, protists share features with plants, animals, and fungi however, are not plants, animals, or fungi

The first organisms on land likely were

plants

What trait do ferns, gymnosperms, and angiosperms share?

vasculature Meaning they all have conducting tissue that they use to transport nutrients and water