BISC102 Lab Exam Spring 2023

Antheridium

the saclike male reproductive organ found in fungi, mosses, ferns, and many other nonflowering plants. It is attached to the gametophyte by a slender stalk. It produces and stores numerous sperm cells.

Archegonium

the female reproductive organ in ferns and mosses. A flask-shaped structure, it consists of a neck, with one or more layers of cells, and a swollen base—the venter—which contains the egg.

Conjugation

the process by which one bacterium transfers genetic material to another through direct contact. During ______, one bacterium serves as the donor of the genetic material, and the other serves as the recipient. The donor bacterium carries a DNA sequence called the fertility factor, or F-factor.

Dikaryotic

Organisms that contain two genetically distinct cell nuclei in the same cell. These organisms consist of genetically dissimilar but have two cell nuclei in the same cell

Diploid

the presence of two complete sets of chromosomes in an organism's cells, with each parent contributing a chromosome to each pair

Embryophyte

land plants that retain the embryo within the female sex organ and protect it during early development. They include mosses, ferns, gymnosperms, and angiosperms.

Gametangium

an organ or cell in which gametes are produced. It’s a haploid structure, and the formation of gametes doesn’t involve meiosis.

Haploid

A cell with a single set of chromosomes (n).

Hypha

a long, branching, filamentous structure of a fungus, oomycete, or actinobacterium

Mycelium

A network of fungal thread or hyphae. Often grows underground but can also thrive in other places such as rotting tree trunks. A single spore can develop into this.

Rhizoid

a short, thin filament found in fungi and in certain plants and sponges that anchors the growing (vegetative) body of the organism to a substratum and that is capable of absorbing nutrients

Sorus

a yellow-brown cluster of structures that produce spores. It is found usually on the lower surface of the leaves of ferns

Sporangium

a structure in certain plants and other organisms that is charged with making and storing spores

Spore

a reproductive cell that certain fungi, plants (moss, ferns), and bacteria produce. Differ from gametes because it does not need to fuse with another reproductive cell.

Zygote

fertilized egg cell that results from the union of a female gamete (egg, or ovum) with a male gamete (sperm)

Zygosporangium

A thick-walled structure that arises from a zygote formed by the fusion or conjugation of two hyphal branches, produces spores, and is characteristic of the Zygomycetes

Biological fitness

a quantitative representation of individual reproductive success. It is also equal to the average contribution to the gene pool of the next generation, made by the same individuals of the specified genotype or phenotype

Directional Selection

describes one of three possible outcomes of natural selection in a specific population and environment. Directional selection is defined as the change in a phenotype or genotype of a population in one direction away from the mean (average) in a particular environment over time.

Gene Pool

the set of all genes, or genetic information, in any population, usually of a particular species

Heritable Variation

the variance of the breeding values among individuals, σ A 2 , which is known as the additive genetic variance.

Null hypothesis

The statistical hypothesis that states that there will be no differences between observed and expected data.

Alternate Hypothesis

the statement you test when attempting to disprove the null hypothesis.

Hypothesis

An idea that proposes a tentative explanation about a phenomenon or a narrow set of phenomena observed in the natural world. This is the backbone of all scientific inquiry

Natural selection

the differential survival and reproduction of individuals due to differences in phenotype. It is a key mechanism of evolution, the change in the heritable traits characteristic of a population over generations

Replication

the differential survival and reproduction of individuals due to differences in phenotype. It is a key mechanism of evolution, the change in the heritable traits characteristic of a population over generations

Sexual dimorphism

the differences in appearance between males and females of the same species, such as in color, shape, size, and structure, that are caused by the inheritance of one or the other sexual pattern in the genetic material.

Sexual selection

results from a specific type of nonrandom mating in which an organisms phenotype influences its ability to attract mates

Statistically significant difference

indicates only that the difference is unlikely to have occurred by chance. It does not mean that the difference is necessarily large, important, or significant in the common meaning of the word

Tradeoffs

when one trait cannot increase without a decrease in another (or vice versa)

Independent variable

the variable that is manipulated during an experiment, and it gets its name because it is independent of other factors

Dependent Variable

the variable that changes as a result of the independent variable manipulation

Ancestral Trait

traits inherited from the common ancestor of two different clades

Character State

mutually exclusive features among taxa of a single paralog-equivalent assemblage that exhibit orthologous relationships to each other

Clade

a grouping that includes a common ancestor and all the descendants (living and extinct) of that ancestor

Convergent Evolution

occurs when organisms that aren't closely related evolve similar features or behaviours, often as solutions to the same problems.

Derived Trait

newly evolved features that did not appear in the ancestors of a lineage

Divergent Evolution

The process by which different organisms having common ancestors develop different traits or characteristics to adapt to the changing environmental conditions and needs

Homoplasy

the development of organs or other bodily structures within different species, which resemble each other and have the same functions, but did not have a common ancestral origin

Homology

similarity of the structure, physiology, or development of different species of organisms based upon their descent from a common evolutionary ancestor

Ingroup

the group of living organisms whose relationships are being considered in a cladogram

Monophyletic Taxon

used to describe a group of organisms that are classified in the same taxon and share a most common recent ancestor. A monophyletic group includes all descendants of that most common recent ancestor

Outgroup

a species or group of species that is closely related to but not part of the group being studied. t serves as a reference point for determining evolutionary relationships within the group under study.

Phylogeny

the study of relationships among different groups of organisms and their evolutionary development

Phylogenetic Tree

a diagram that depicts the lines of evolutionary descent of different species, organisms, or genes from a common ancestor

Paraphyletic Group

a group of any size and systematic rank that originated from a single common ancestor, but does not – as opposed to a monophyletic group – contain all descendants from this ancestor

Polyphyletic group

an assemblage that includes organisms with mixed evolutionary origin but does not include their most recent common ancestor

Sister Taxa

pairs of terminal taxa and/or clades that branch from a common node and are often considered closely related

Banded Iron Formation

sedimentary rock formations with alternating silica-rich layers and iron-rich layers that are typically composed of iron oxides

Cambrian Explosion

happened more than 500 million years ago. It was when most of the major animal groups started to appear in the fossil record, a time of rapid expansion of different forms of life on Earth

Microbialite

organosedimentary deposits that have accreted as a result of a benthic microbial community trapping and binding detrital sediment and/or forming the locus of mineral precipitation

Paleoecology

the study of interactions between once-living organisms and their environmental surrounding

Paleolake

An ancient lake, especially one that no longer exists

Stromatolite

layered deposit, mainly of limestone, formed by the growth of blue-green algae (primitive one-celled organisms). These structures are usually characterized by thin, alternating light and dark layers that may be flat, hummocky, or dome-shaped

Trace Fossil

a fossil that provides indirect evident evidence of ancient plants or animals, such as footprints, nests, burrows, or feces.

Trackway

a series of fossil footprints

Allele

One of two or more versions of a genetic sequence at a particular region on a chromosome.

Autosomal Chromosome

one of the numbered chromosomes, as opposed to the sex chromosomes

Autosomal Gene

the gene in question is located on one of the numbered, or non-sex, chromosomes

Diploid Cell

the presence of two complete sets of chromosomes in an organism's cells, with each parent contributing a chromosome to each pair

Dominant Allele

produces a dominant phenotype in individuals who have one copy of the allele, which can come from just one parent. For a recessive allele to produce a recessive phenotype, the individual must have two copies, one from each parent

Gene

the basic physical and functional unit of heredity. Made up of DNA.

Genotype

the genetic makeup of an organism

Haploid Cell

a cell that contains a single set of chromosomes

Heterozygous

having different alleles for a particular trait. The relationship between the two alleles affects which traits are expressed

Homologous Chromosomes

paired chromosomes. They essentially have the same gene sequence, loci (gene position), centromere location, and chromosomal length. Although they may have the same genetic sequence and loci, they may differ in alleles

Homozygous Recessive

an organism with two recessive alleles

Homozygous Dominant

an organism with two dominant alleles

Phenotype

the observable expression of a genotype

Recessive Allele

A type of allele that when present on its own will not affect the individual

Sex Chromosome

a type of chromosome involved in sex determination

Sex-Linked Gene

refers to characteristics (or traits) that are influenced by genes carried on the sex chromosomes

Sister Chromatids

the identical copies (chromatids) formed by the DNA replication of a chromosome, with both copies joined together by a common centromere

Tetrad (=bivalent)

A four-part structure that forms during prophase I of meiosis and consists of two homologous chromosomes, each composed of two identical chromatids

Behavior

the change in activity of an organism in response to a stimulus

Proximate Causation

an event which is closest to, or immediately responsible for causing, some observed result

Ultimate Causation

the past conditions having led to the information encoded in DNA

Pheromone

chemical substances that are created and emitted by organisms as odorants—often as oils or sweat—into the environment that may influence the behavior or physiology of other members of their species

Adaptive Radiation

process in which organisms diversify rapidly from an ancestral species into a multitude of new forms, particularly when a change in the environment makes new resources available, alters biotic interactions or opens new environmental niches

Allopatric Speciation

occurs when a species separates into two separate groups that are isolated from one another. A physical barrier, such as a mountain range or a waterway, makes it impossible for them to breed with one another

Benthic Zone

the lowest ecological zone in a water body, and usually involves the sediments at the seafloor

Limnetic Zone

the layer of open water where photosynthesis can occur. As one descends deeper in the limnetic zone, the amount of light decreases until a depth is reached where the rate of photosynthesis becomes equal to the rate of respiration

Biological Species Concept

defines a species taxon as a group of organisms that can successfully interbreed and produce fertile offspring

Coevolution

occurs when two or more species reciprocally affect each other's evolution through the process of natural selection

Founder Effect

the reduction in genomic variability that occurs when a small group of individuals becomes separated from a larger population

Genetic Drift

is the change in the frequency of an existing gene variant in a population due to random chance

Sympatric Speciation

involves the splitting of an ancestral species into two or more reproductively isolated groups without geographical isolation of those groups

Australopithecine

were terrestrial bipedal ape-like animals that had large chewing teeth with thick enamel caps, but whose brains were only very slightly larger than those of great apes. Is a collection of hominin species that span the time period from 4.18 to about 2 million years ago

Extant

one which has survived to the present day, and so it is a living group. This distinguishes it from an extinct group.

Foramen Magnum

a large, oval-shaped opening in the occipital bone of the skull. It is one of the several oval or circular openings (foramina)

Hominin

the group consisting of modern humans, extinct human species and all our immediate ancestors

Prognathy

when your jaw protrudes, or juts out. This typically involves your lower jaw.

Mark recapture

used to estimate the size of a population where it is impractical to count every individual. The basic idea is that you capture a small number of individuals, put a harmless mark on them, and release them back into the population

Mutualism

the ecological interaction between two or more species where both species benefits

Symbiosis

any type of a close and long-term biological interaction between two biological organisms of different species, termed symbionts, be it mutualistic, commensalistic, or parasitic

Canopy

the aboveground portion of a plant cropping or crop, formed by the collection of individual plant crowns

Coniferous Tree

made up of living and fossil gymnospermous plants that usually have needle-shaped evergreen leaves and seeds attached to the scales of a woody bracted cone

Deciduous Tree

those that lose all of their leaves for part of the year

Fauna

Flora

all of the animal life present in a particular region or time

Herbivory

a form of consumption in which an organism principally eats autotrophs such as plants, algae and photosynthesizing bacteria. More generally, organisms that feed on autotrophs in general are known as primary consumers