Biology Final Exam

What is pollination?

Pollination is the transfer of pollen to the part of the seed plant containing the ovules.

Reproductive isolation

The existence of biotic or abiotic factors that prevent two species from producing viable fertile offspring

Biological species concept

A group of organisms that can successfully interbreed and produce fertile offspring

What is endosymbiosis?

Prokaryotic cells that enter into other cells

What is the morphological species concept?

It characterizes species by body shape and other structural features

What is phenotypic plasticity?

Changes in an organism's behavior, morphology, and physiology in response to a unique environment

What is the central dogma of DNA ?

Information from DNA is transcribed to RNA, which is translated into amino acids, which are folded into proteins

What are three types of interactions between species?

Competition is when two or more species are fighting for the same resources, negative/negative. Parasitism is when a parasite lives off of a host, who is harmed, but not normally killed, positive/negative. Mutualism is when two or more species are able to provide a benefit to each other, positive/ positive.

What is the definition of a shared derived character?

A trait unique to a single clade

What is the difference between microevolution and macroevolution?

Microevolution is changes in allele frequency and macro evolution is large patterns of evolution throughout a long period of time,

What are the three sources of evolution?

Natural selection, genetic drift, and gene flow. Natural selection and genetic drift are random, while gene flow is through migration.

What is homology?

Pomology is characteristics in organisms that have similarities and share ancestors even if they have different uses.

How does genetic variation and inheritance patterns contribute to evolution and the diversity of life?

Genetic variation, caused by mutations, gene flow, and recombination, provides the basis of evolution. Inheritance patterns like Mendelian genetics and processes like genetic drift determine how traits are passed. Over time, genetic variation leads to adaptations and speciation. Genetic mechanisms like DNA replication and meiosis ensure that variation is maintained, while environmental factors influence which traits are beneficial.

What is the difference between homologies and analogies?

Homologies are shared traits due to shared ancestors and analogies are traits that have the same function but a different source

What are prezygotic and postzygotic barriers?

Prezygotic barriers block fertilization due to physical barriers, different mating times, courtship behaviors, reproductive structure, or gamete compatibility. Postzygotic barriers stop successful reproduction after the zygote is formed due to infertile offspring, reduced survival rates, different chromosome numbers, or sterile F2 hybrids.

Natural selection

Picks favored mutations

Genetic drift

Random fluctuation in allele frequency from generation to generation, loss of variation

Gene flow

Transfer of alleles into or out of a population which reduces genetic differences between populations

What are adaptations?

Characteristics of an organism that enhance its survival or reproduction in a specific environment

What are the four types of macromolecules and describe them?

The four types of macromolecules are carbohydrates, lipids, protein, and nucleic acids. Carbohydrates are sugar molecules and known for being able to be divided into three categories: monosaccharides, disaccharides, and polysaccharides that provide short term energy. Lipids are composed of glycerol and fatty acids. There are two types of fatty acids: saturated that have no double bonds and unsaturated that have one or more double bonds. Lipids can be divided into three types: phospholipids, steroids and waxes, and triglycerides. They provide structural support for the cell. Proteins are made of amino acids and are used to build and repair tissues. Nucleic acids can be divided into two types: DNA and RNA and nucleic acids store, transmit, or express genetic information.

What is ecology and what are the six levels?

Ecology is the study of the interaction between organisms and their environment. The six levels are organismal, population, community, ecosystem, landscape, and global. Organismal focuses on one organism, population focuses on a group of individuals living in an area, community focuses on a group of populations interacting, ecosystem focuses on biotic and abiotic factors in a community, landscape focuses on a mosaic of ecosystems, and global looks at the entire world.

What is speciation and what are the two types?

Speciation is the process that splits one species into two or more species. The two types are allopatric and sympatric. Allopatric speciation is when a species becomes separated into two groups due to physical isolation. Sympatric speciation is when polyploidy, habitat differentiation, or sexual reproduction causes speciation in organisms that live in the same area.

What is adaptive radiation?

Organisms diversify rapidly from an ancestral species into a multitude of new forms, usually from a change in the environment that introduces new resources

Why do RNA viruses have a higher mutation rate than DNA viruses?

RNA strands are more unstable

Why did the beak sizes of Galapagos finches change over time?

They were adapting to the food sources available that helped increase survival rates

What are the chromosome structural differences between a eukaryote and a prokaryote?

A eukaryotic chromosome is linear and x-shaped whereas a prokaryote chromosome is circular

What are the three possible outcomes of hybridization and what are they?

Reinforcement is when offspring between the two species are less fit which prevents hybridization. Fusion is when offspring between the two species create a new species thus being beneficial. Stability is when nothing changes.

What are the three stages of the Calvin cycle?

Reduction, regeneration, and Carbon fixation

What are the four main factors of climate?

Temperature, sunlight, precipitation, and wind.

What is the definition of polytomy?

It's a node where two or more groups emerge

What is the mutation rate in plants and animals per generation?

1 in 100,000

What are the three biotic factors that causes a species to be absent from an area?

Parasitism, competition, and predation

What is the order of the different plant types from oldest to newest?

Nonvascular, seedless vascular, gymnosperms, angiosperms

What is sister taxa?

Groups of taxa sharing an immediate ancestor

T or F: mutations are a source of evolution

True

Compare catastrophism and uniformitarianism

Catastrophism: the earth is relatively young and was created through catastrophic events. Uniformitarianism: The earth is old and was formed through natural processes

What is the difference between a homozygote and a heterozygote?

A homozygote is two identical alleles for a gene and a heterozygote is two different alleles for a gene

What is the root, node point, and tip in a phylogenetic tree?

The root is the common ancestor, the node point is the point where species diverge, and the tip is the living species

What are the four types of species concepts?

Biological species concept, ecological species concept, morphological species concept, and phylogenetic species concept

What is the difference between intrasexual and intersexual selection?

Intrasexual selection is the competition within the same sex, often males. Intersexual selection is female choice, males attempt to attract female in some sort of way and females choose the best

What are the different types of macromolecules?

Lipids, carbohydrates, proteins, and nucleic acids

What are the advantages of seed plants?

Seed plants have a protective shell that allows the seed to travel larger distances then those plants that repopulate with spores due to the protective shell being nutrient packed

What tells us how organisms are named and organized?

Taxonomy

What is speciation and why is it important?

Speciation is the process in which one species would split into 2 or more species. It's important because it explains the differences and similarities of life within species

What are the two different types of traits?

Discrete traits are ones that we can categorize easily, like pea color being green or yellow. Continuous traits are ones that we can't categorize easily, like height

Define homologous traits and structures and their difference from vestigial structure

Homologous traits are traits that are the same due to shared ancestry, despite them serving different functions. Homologous structure would be variation of structure in an ancestor.it is different than vestigial structure because those are the remnants of traits or features that served a key function in ancestors

What's the difference between a phenotype and a genotype?

A phenotype refers to the physical traits of an organism while genotype refers to the genetic makeup of an organism

What is the difference between natural selection and evolution?

Natural selection acts on an individual while evolution acts on a population

What are three edible examples of fermentation?

Cheese, wine, and bread

What are two reasons why fungi is important?

Food spoilage and plant pathogens

What is phylogeny?

The evolutionary history of a species or group of species

T or F: evolution is goal oriented

False

What does hybrid mean?

Offspring of interspecific mating

What are the survivorship curves?

Type one is when a lot of younger organisms make up the population and as time goes on they die as they get older, like humans and elephants. Type two is when organisms die at a constant rate, like birds. Type three is when organisms are more likely to die at a younger age and if they survive they usually live a very long time, like trees and turtles.

What are the three key requirements for natural selection?

Natural variation in the population, traits have to be heritable, and some variants must survive and reproduce

What is a shared derived character?

A trait unique to a single clade

What is the aphotic zone?

The zone where no light penetrates the ocean

What are lipids and the main types?

Lipids are macromolecules made of fatty acid monomers, that function as structural support for the cell energy storage and cell signaling. Lipids are non polar in nature and don't interact with water. The main types are triglycerides, phospholipids, and steroids and waxes.

What is a binomial nomenclature?

A naming system where the name has two parts

Which of the four species concepts is the most popular?

The phylogenetic species concept

What is the difference between a dominant species and a keystone species?

A dominant species is the species with largest biomass. A keystone species is less abundant, but is the most important. If the keystone species is removed, it will impact the entire community.

What are hybrid zones?

Regions where members of different species meet and mate, producing at least some hybrid offspring

T or F: mutation rates are lower in plants and animals and higher in viruses

True

What are the eight levels of species classification?

Domain, kingdom, phylum, class, order, family, genus, species

What does it mean to be a heterotrophic absorber?

An organism or molecule that absorbs energy or nutrients from external organic sources (external digestion)

Explain the process of dehydration reaction and hydrolysis in correlation with each other

A dehydration reaction occurs when two monomers bond together through the loss of a water molecule. Polymers are disassembled into monomers by hydrolysis

What is the morphological species concept?

Categorizing species by body shape and other structural features

What are three differences between monocots and dicots?

Monocots typically have parallel veins, they only have one cotyledon, and have a fibrous roof system. Dicots have net like veins, two cotyledons, and a taproot (one main root)

T or F: you can rotate a node on a phylogenetic tree and it will still have the correct information

True

What is a pseudogene?

Looks like a gene, but isn't. They are protein forming regions that have lost their promoter

What did Carolus Linneaus do?

Created the modern naming system of organisms

What shape is DNA?

Double helix

What are cladistics?

A system where common ancestry is the primary criterion

What is a mutation?

A change in the nucleotide sequence of an organism's DNA

Why is vascular tissue important?

Most plants have vascular tissue, in which cells are joined into tubes to transport water and nutrients. The plants that have a complex vascular system are known as vascular plants. Non vascular plants lack the extensive transport system.

What are the three levels of dispersion?

Uniform is when the species are evenly distributed throughout the area and do not like to cross over, like territorial animals. Random is when the species live wherever and do not care too much about it. Clumped is when species group together and typically share similar resources, like a herd of zebras near a watering hole.

What do the lines on a phylogenetic tree represent?

The way species are connected and their evolutionary relationships with other species and groups. It also shows the shared similarities. When a long line appears, it represents a long period of time.

Why are hybrid zones not always good?

Since they are small regions, lots of hybrids are produced and that includes unfit species. This occurred with fire-bellied and yellow-bellied toads, where the unfit hybrids had fused ribs, mutant parts, and nonfunctional valves.

Why are large mutations almost always bad?

They can disrupt, delete, or rearrange genes

T or F: fungi are more closely related to animals than plants

True

Explain the difference between population and community

Populations are groups of individuals of the same species living together. Communities are groups or individuals of different species living together in the same area.

Explain the chromosome theory of inheritance

Mendelian genes have specific loci along chromosomes, and it is the chromosomes that undergo segregation and independent assortment

What causes a neutral variation?

Point mutations in noncoding regions

What is paleontology the study of?

Fossils

Where does transcription occur in eukaryotes and prokaryotes?

In eukaryotes, transcription occurs in the nucleus, and occurs in the cytoplasm for prokaryotes

T or F: males and females are included in the calculations for reproductive rates

False, only females included

What type of cladogram are marine mammals in?

Polyphyletic

What is the source of all new traits/alleles in an organism?

Mutations

T or F: gymnosperms are seedless plants

False

What is the root of a phylogenetic tree?

The common ancestor of all the species

Which species concept is based on the niche concept?

The ecological species concept

What is a cline?

A gradual change in a characteristic along a geographic axis

What are three limitations of natural selection?

Not forward looking, cannot create new traits, non progressive / not goal oriented

What is a Barr body?

A Barr body can exist within any cell that has two full chromosomes or two x chromosomes. A Barr body occurs when a cell chooses a dominant chromosome and the other condenses and goes to the side of the cell.

What are independent and dependent factors that affect density?

Independent factors are natural occurrences like fires or droughts. Dependent factors include the negative feedback loop between population and r values, competition, predation, disease, parasites, and stress.

If the allele frequency would remain constant what needs to occur and what is it called?

It is called the Hardy-Weinberg. What would need to happen is no selection on population, no migration no random alleles influencing the population, no mutations.

Why do scientists measure average heterozygosity?

To determine population health. If the heterozygosity is high, the population is doing well and there is limited in breeding. Heterozygosity helps mask negative recessive genes so it is good for the population to be heterozygous.

What is meiosis?

Meiosis is preceded by the replication of chromosomes and takes place in two consecutive cell divisions called meiosis one and two.

What is a niche?

The role an organism plays in their environment

What are the three stages of synthesis in an RNA transcript?

Initiation, elongation, termination