Bio exam 1

What did the Human Microbiome Project demonstrate?

A person walking through a room will leave behind millions of individual microbes from hundreds of species.

Select the statement that correctly describes the evolutionary relationships among the domains of life.

Archaea and Eukarya are more genetically similar than Archaea and Bacteria.

What are the three domains of life?

Bacteria, Archaea, Eukarya

Why is a bunny that glows green after given a piece of jellyfish DNA strong evidence for the idea of all living organisms share part of their evolutionary history?

Because they have to be closely related to be able to transfer DNA like they did in the expirement. Their genetic codes have to be very similiar

Marsupials

Carry and feed young in a ventral pouch. Young are born early, and crawl into pouch for further development. Most are in Australia and South America

What happens in convergent evolution?

Two distantly related species independently develop similar traits.

how can fossils be fossilized?

Unaltered: Frozen, mummified, trapped in amber or sap. Altered: minerilization turning it into stone, carbonized

Scientists are continually discovering new species of prokaryotes. Why is DNA testing important in identifying new prokaryotic species?

Unique DNA sequences help to determine if the prokaryote is a new species.

How do homologous and vestigial structures support the theory of evolution?

Vestigial structures are body parts that have lost their use through evolution. Homologous structures are structures that have a common function and suggest common ancestry. Examples: Homology: human digits and monkey digits Vestigial: Human tail bone

The community of microbes living in or on our bodies is called _________.

the human microbiome

What did Carl Woese use to group organisms into three distinct domains?

the sequence of an rRNA molecule

What is a phenotype?

the set of observable characteristics of an individual resulting from the interaction of its genotype with the environment.

Which statement is the definition of biogeography?

the study of species distributions across the planet

The Cambrian explosion was

the sudden diversification of animal life from simple organisms to all of the basic body types known today.

is variation in a population of organisms always sufficient for survival when the organisms are confronted with the pressures of a changing environment? Why or why not? (hint: think about extinction)

the variation in any generation may be insufficient for survival, particularly during periods of relatively fast environmental change.

Our own phylum, Chordata, is distinguished by four features

• (1) a dorsal, hollow nerve cord; • (2) a notochord; • (3) pharyngeal slits; and • (4) a post-anal tail

what is radial symmetry

symmetry around a central point

what is taxonomy?

systematically identifying, naming, and classifying organisms on the basis of shared traits

There are three lineages of jawed fishes

- Chondrichthyes includes sharks and rays (cartilage skeletons, no bones) - Ray-finned fishes and lobe-fins have lungs (or lung derivatives) - Lobe-finned fishes have muscular fins supported by stout bones

Chondrichthyans

- Sharks and rays have a flexible skeleton made of cartilage

Lobe-limbed vertebrates

- Three extant groups: - Coelacanths - Lungfishes - Tetrapods

Does environmental challenges result in organisms changing to meet those challenges? Does environmental change cause variation to increase or appear in populations? Does the need of an organism to survive cause variation to appear?

1- a population with varied inherited traits -2. Elimination of beetles with lighter shells-3.increasing frequency of traits that enhance survival and reproduction success A trait that allowed them to succeed continues to be passed down leading to the whole population sharing this trait or a new species being formed. Variation is present, and sometimes result

Challenges for Life on Land

1. Mass and Structural Support 2. Locomotion 3. Air Breathing 4. Feeding 5. Sensory 6. Water Balance 7. Reproduction

What is bilateral symmetry

: symmetry in which similar anatomical parts are arranged on opposite sides of a median axis so that only one plane can divide the individual into essentially identical halves.

what is true about animals?

A key adaptation that helped animals to move onto land was the evolution of an exoskeleton.

What is a scientific theory? How is it different from the informal use of the word 'theory'?

A scientific theory is a hypothesis that's been tested again and again and has come up to be true so far. In the informal use of the word theory it means to hypothesize without any significant testing done.

10. Explain how and why adaptive radiations occur. Use the marsupial example in your explanation.

An adaptive radiation occurs when a single or small group of ancestral species rapidly diversifies into a large number of descendant species. Among factors that can trigger an adaptive radiation, ecological opportunity is probably foremost. Marsupials crossed across many continents to get there when they were all connected as pangea.

what makes you a vertebrate?

Animals that have a backbone are called vertebrates. The backbone is is a column of bones that supports the body, and also protects the spinal cord. The back is made up of many separate bones, called vertebrae. The backbone is part of a vertebrate's supportive internal skeleton.

define arthropods

Arthropods are invertebrate animals having an exoskeleton, a segmented body, and paired jointed appendages.

To the level of detail described in lecture, explain how is the information in a DNA molecule is used to (eventually) direct the production of a functional protein.

DNA-> RNA -> Protein t he enzyme RNA polymerase (green) uses DNA as a template to produce a pre-mRNA transcript (pink). The pre-mRNA is processed to form a mature mRNA molecule that can be translated to build the protein molecule (polypeptide) encoded by the original gene.

What is anecdotal evidence?

Derived from personal observation, little data considered, conclusions not verified, published on social media

What is the primary difference between bacterial and eukaryotic cells?

Eukaryotic cells have membrane‑bound compartments called organelles, whereas bacterial cells do not.

Can you define evolution in under 10 words? Explain how unequal reproductive success leads to evolution in populations.

Evolution is change in the heritable characteristics of biological populations over successive generations. Unequal reproductive success leads to evolution in populations because if all the white beatles are being eaten then there will be no white beatles to reproduce, but the brown beatles will still live.

What is an allele?

Eye color = a character (trait) Can change in a population Can change overtime by introducing new alleles The more successful alleles continue because they produce off spring the most frequently

what are angiosperms

Flowering Plants

What is a fossil?

Fossil: the preserved remains or the impressions of once living organisms

How do fossils lend support for the theory of evolution?

Fossils support the theory of evolution by showing how life came to be, for example how tetrapods came to land and evolved.

What are gymnosperms

Gymnosperms have no flowers or fruits and have naked seeds on the surface of their leaves. Gymnosperm seeds are configured as the cones.

How do the finches of the Galapagos islands show the unity and diversity of life?

He concluded that one species rose to 14 different species. The finches' beaks adapted to its particular diet.

Natural selection is a mechanism of evolution. What is doing the selecting in natural selection?

How does natural selection work? In natural selection, genetic mutations that are beneficial to an individual's survival are passed on through reproduction. This results in a new generation of organisms that are more likely to survive to reproduce.

independent variable, dependent variable, and control group

Independent variable: The one the researcher changes control group: the one the researchers keeps the same dependent variable: the one that is showing you your results because it depends on the independent variable

Eutherians

Mammal eggs are fertilized internally; embryos develop in the female uterus. Embryo is contained in an amniotic sac that is homologous to one of the membranes of the amniote egg. A placenta connects the embryo and uterus wall for nutrient and gas exchange and waste elimination via the female's circulatory system.

What organisms produced oxygen on earth? What biological process resulted in this oxygen production? Why is the Great Oxygenation Event sometimes called earth's first pollution crisis?

Photosynthesis by cyanobacteria caused the GOE. Dissolved iron in the seas where life arose Certain bacteria found a way to split water apart during photosynthesis.... Generating O2 waste The oxygen reacted with iron to make insoluble iron oxide Banded iron formations are the earliest evidence of photosynthesis. and it is referred to the earths first pollution crisis because it killed off many species

Which of the following is true about plant defenses?

Plants are able to release chemicals that both repel pests and attract the pest's predators.

How are fossils dated?

Relative dating: Aged based on layers of rock of fossils of known age Fossils are at least as old as the rocks that incase them Radiometric dating: Uses radioactive isotopes to measure age of fossil or surrounding rocks

Chemicals produced by plants that are not directly involved in growth or reproduction but that help protect the plant by their impacts on other organisms are called _____.

Secondary metabolites.

what is true stomata

Stomata are cell structures in the epidermis of tree leaves and needles that are involved in the exchange of carbon dioxide and water between plants and the atmosphere.

How can a mass extinction lead to explosive diversification of species?

Surviving species rapidly evolve and diversify to fill empty niches.

what are tetrapods?

Tetrapods are four-limbed vertebrate animals constituting the superclass Tetrapoda. It includes extant and extinct amphibians, reptiles, and synapsids.

phylogeny

The evolutionary history of a group of organisms • Represented by a diagram called a phylogenetic tree

How similar is the genetic code between organisms? What does this mean?

The genetic code is nearly identical among all organisms Closely related organisms share DNA sequences Closely related species have fewer DNA sequence differences than species more distantly related

• What is the largest group of organisms?

The largest group of classification systems is the kingdom which includes one or more related divisions with less number of common characters between organisms. Kingdoms are mainly - Monera, protists, fungi, Plantae and Animalia.

homologous vs analogous

The limbs of vertebrates are examples of homologous structures, and in fact the same bones are present, yet modified from one animal to another. The wings of insects and birds are examples of analogous structures with completely different evolutionary paths and origins

What do birds, reptiles, amphibians, and fish all have in common?

They all share a common ancestor with the echinoderms.

What is a characteristic of nonvascular plants

They are small and low to the ground.

Mosses and liverworts are early colonizers during ecological succession and make the environment more amenable for other species. How do these plants contribute to nitrogen levels in the soil?

They house nitrogen‑fixing cyanobacteria in their tissues.

Because extremophiles are hard to culture outside of their native environments, how do scientists classify and identify specific species?

They use DNA sequencing to identify species via genetic differences.

What is the difference between anecdotal evidence and scientific evidence

While scientific evidence can be independently verified using the scientific method, anecdotal evidence cannot.

Movement in the animal kingdom first evolved along with

a body plan that had symmetry.

Which phrase best describes evolution?

a change in the frequency of alleles in a population over time

what is a cladogram

a graph that represents phylogeny

What is a pathogen?

a microorganism or virus that infects a host organism and is capable of causing a disease in the host organism

what are monotremes

a primitive mammal that lays large yolky eggs and has a common opening for the urogenital and digestive systems. Monotremes are now restricted to Australia and New Guinea, and comprise the platypus and the echidnas. —duck-billed platypus and echidnas; lay shelled eggs, and have sprawling legs

What is a statistically significant result?

a statistically significant result (usually a difference) is a result that's not attributed to chance.

Hawaiian honeycreepers comprise a number of bird species that are found only on the Hawaiian islands. The images show examples of two distinct honeycreeper species. Each honeycreeper species exhibits phenotypic differences in characteristics, such as beak shape and plumage color. All of the Hawaiian honeycreeper species are believed to have evolved from a common ancestor as the birds began to occupy different ecological niches on the Hawaiian islands.

adaptive radiation

- cell membrane

allows the interior to be different from exterior. Made of lipids and proteins

what was the first vertebrate to move to land

amphibians

what are anthropods

an invertebrate animal of the large phylum Arthropoda, such as an insect, spider, or crustacean.

whats an extremophile?

an organism that thrives in extreme conditions

According to their numbers, what are the most successful animals on the planet?

arthropods

Why don't we have earth rocks that are more than 4 billion years old?

because the rock slowly turns to lead

What type of body symmetry is found in animals that can move swiftly?

bilateral

- genetic material

chromosomes carrying genes made of DNA

What are the main features of a scientific hypothesis?

derived from systematic observation and experimentation, lots of data and uses statistics, conclusions go through peer-review

The variation in shape and function of the forelimb in tetrapods is a result of

different environments leading to the evolution of different types of limbs.

In which type of selection does a change in the environment make it so that individuals with one type of extreme trait survive and reproduce at higher rates than other individuals?

directional selection

The absence of membrane-bound organelles in a cell tells you that the cell must be

either from a member of the domain Bacteria or from a member of the domain Archaea.

6. What features define animals and distinguish them from other organisms?

eukaryotic, multicellular organisms, and almost all animals have specialized tissues. Most animals are motile, at least during certain life stages. Animals require a source of food to grow and develop. All animals are heterotrophic, ingesting living or dead organic matter.

Which types of plants possess true stomata?

ferns, angiosperms, mosses

Which feature makes angiosperms different from all the other types of plants?

flowers

What is homology?

homology is similarity due to shared ancestry between a pair of structures or genes in different taxa

The forelimb of a chicken and a primate contain many of the same bones arranged in the same order. This is an example of

homology.

What can we learn about vertebrate evolution from Tiktaalik that we did not know before?

how vertebrates evolved tetrapod limbs

what do Amniotic reptiles include

include lizards, snakes, turtles, crocodilians, and birds Terrestrial adaptations of reptiles include scales, waterproofed with keratin

What are lobed fish

is a clade containing the coelacanths, lungfishes, tetrapods, and their fossil relatives

ribosomes

make the proteins encoded by the DNA as directed by RNA

what are the characteristics of an autotroph?

make up the base of food chains, are producers, make their own food using inorganic carbon and energy

Describe the characteristics of marsupials that distinguish them from other mammals. What kinds of traits are most useful in understanding how organisms are related to each other?

mammals are characterized by the presence of mammary glands to feed the young whereas marsupials are characterized by the presence of a pouch to carry the young.

Which trait is one of the defining characteristics of all mammals?

mammary glands

The scientific method has assumptions (or boundaries): materialism, cause & effect, and reproducibility. Explain each

materialism: Assumes that effects in the natural world all have natural causes, rather than supernatural ones.The assumption of materialism is required for science to workcause and effect: Science assumes that the rules for cause and effect hold for all natural phenomena.Every event in nature has a cause and since cause & effect are related, a scientist can learn about causes by observing the effects that occurreproducibility: Science assumes all events are consistent and repeatable - if the same causes are set up, the same effects will occur-Experimental repetition makes science self-correcting - individuals can make mistakes in an experiment and scientists repeating these experiments can weed out the mistakes

what are the characteristics of heterotrophs

occupy the upper levels of the food chain, eat other organisms for food, are consumers

Convergent evolution?

organisms that are not closely related evolve similar adaptations as a result of independent episodes of natural selection

Which term is not present in bryophytes?

phloem cells

What was responsible for enriching Earth's atmosphere with oxygen?

photosynthesis by cyanobacteria

Evolution of pollen and seeds were key evolutionary milestones that allowed for

plants to succeed and diversify on land.

Common to all cells

plasma membrane DNA ribosome

what do land plant cells have

plasmodesmata that serve in communication between cells

characteristics of seed plants

produce seeds, transport sugar through phloem, do not require water for reproduction

What are extreme thermophiles?

prokaryotes that thrive in extremely hot environments, such as boiling hot springs

what is the bilateral symmetry animals divided into

protostomes and deuterostomes.

Echinoderms include species like starfish, sea urchins, and sea lilies.

radial symmetry

what follows mass extinction?

rebound in diversity follows mass extinctions, survivors become adapted to vacant ecological niches

Bacilli

rod shaped

Unique to eukaryotic cells

rough endoplasmic reticulum nuclear membrane chloroplast

cytoplasm

semifluid of proteins, enzymes, sugars, salt

Could we support the theory of evolution without fossils?

similarities among organisms alive today, similarities in DNA, and similarities of embryos, homology.

How are fossils formed

sometimes the fossils are trapped in ice, sometimes preserved in amber Organisms can be preserved by rapid burial in sediment layers, if the organism is covered quickly enough and bacteria can't break It down. Organisms don't actually have to be there, but their indentation in the hardened earth can reveal their skeleton Organisms can be fossilized by mineralization

A vascular system is the _______.

specialized plant tissues that transport water and nutrients

Cocci

spherical bacteria

spiral shaped

spirilla

In which type of selection are intermediate traits favored over more extreme variations of a trait?

stabilizing selection

what did birds evolve from

theropods

For most of the history of life on earth, where have living organisms lived? How big were organisms until the most recent ~550 million years?

they were small aquatic

whats the point of the fossil record

to track change over time

Characteristics of moss

transport of sugar by diffusion, limited to short heights, require water for reproduction

What are two major plant adaptations that were most important in allowing plants to become independent of aquatic habitats?

vascular system and seeds