Bio Exam 1

Variable you manipulate, and is the factor you think is driving change in a dependent variable. Found on x-axis (abscissa)

the response variable that depends on the x-axis data. Found on the y-axis (or ordinate)

energy, cells, information, replication, evolution

a highly organized compartment that is bounded by a thin, flexible structure called a plasma membrane and that contains concentrated chemicals in an aqueous solution

all organisms are made of cells, and all cells come from preexisting cells (as opposed to spontaneous generation)

Hypothesis is a testable statement to explain a phenomenon or a set of observations.

Prediction is a measurable or observable result that must be correct if hypothesis is valid.

evidence that life arose from non-life early in Earth's history

Special creation: all species are independent, in the sense of being unrelated to each other, life on Earth is young, and species are immutable (incapable of change)

Descent with modification: species that lived in the past are the ancestors of the species existing today, and species change through time

Pattern: a statement that summarizes a series of observations about the natural world. The pattern component is about facts - how things are in nature.

Process: a mechanism that produces the pattern or set of observations

a similarity that exists in species due to common ancestry (homology = study of likeness) and there are three types: genetic, developmental, and structural homology

NOT survival of the fittest. It is how evolution occurs and must meet two conditions: individuals within a population vary in characteristics that are heritable, and in a particular environment, certain versions of these traits help individuals survive better or reproduce more than do other versions

when natural selection has caused populations of one species to diverge and form a new species

Fitness: an individual's ability to produce viable offspring

Adaptation: a trait that increases fitness of an individual in a particular environment

1. Variation exists among individuals that make up a population

2. Some of the trait differences are heritable (passed on to offspring)

3. Survival and reproduction success is highly variable

4. The subset of individuals that survive best and produce the most offspring is not a random sample

explained how genetic information is transmitted from one generation to the next and shed light on the third fundamental attribute of life: organisms process information

Blending Inheritance: traits observed in mother and father blend together to form traits in their offspring. As a result, an offspring's traits are intermediate between traits of the mother and father (black + white = gray)

Inheritance of Acquired Characteristics: traits present in parents are modified through use and then passed on to their offspring in modified form (giraffe stretches neck and offspring gets longer neck)

Gene: a hereditary factor that influences a particular trait

Allele: a particular form of a gene

Genotype: a listing of the alleles of particular genes in an individual

Genotype: a listing of the alleles of particular genes in an individual

Phenotype: an individuals observable traits (molecular to whole)

Homozygous: having two of the same allele (ex. BB or bb)

Heterozygous: having two different alleles (ex. Bb)

Dominant: an allele that produces its phenotype in heterozygous and homozygous genotypes (BB and Bb where B is dominant)

Recessive: an allele that produces its phenotype only in homozygous genotypes (Bb bb where b is recessive)

Note that "dominant" does not mean more frequent

Pure Line: individuals of the same phenotype, that when crossed, always produce offspring with the same phenotype (pure lines are homozygous for gene in question)

Hybrid: offspring from crosses between homozygous parents with different genotypes (hybrids are heterozygous)

Reciprocal Cross: a cross in which the phenotypes of the male and female are revered compared with a prior cross (same result)

Testcross: a cross of a homozygous recessive individual and an individual with the dominant phenotype but unknown genotype

hereditary determinants for traits do not blend together or become modified through use. Instead, hereditary determinants maintain their integrity from generation to generation - they act as discrete, unchanging particles (contrasts blending inheritance and acquired characteristics)

two members of each gene pair must separate (segregate) into different gamete cells during the formation of egg and sperm. As a result, each gamete contains one allele of each gene

monohybrid cross: a mating between parents that each carry two different genetic determinants for the same trait

Dihybrid cross: a mating between two individuals who are heterozygous for two traits

independent assortment: alleles of different genes don't stay together when gametes form (ex. RY Ry rY ry where RY and ry assort independently) - happens

dependent assortment: alleles of different genes stay together when gametes form (ex. RY stays together and ry stays together) - does not happen

the conclusion made that alleles of different genes are transmitted independently of one another

the division of the nucleus and the division of the cytoplasm

Divides the replicated chromosomes to form two daughter nuclei with identical chromosomes and genes

follows mitosis and divides the cytoplasm of the parent cell to form two daughter cells

G1 Phase: unreplicated chromosomes

S Phase: chromosomes replicated

G2 Phase: replicated chromosomes each with two sister chromatids

....goes on to mitosis

1. Prophase: chromosomes condense, and spindle apparatus forms

2. Prometaphase: nuclear envelope breaks down and microtubules contact chromosomes at kinetochores

3. Metaphase: chromosomes complete migration to middle of cell. They are lined up on metaphase plate

4. Anaphase: sister chromatids separate into daughter chromosomes, which are pulled to opposite poles of spindle apparatus

5. Telophase: nuclear envelope re-forms and chromosomes de-condense and most cells go on to divide their cytoplasm via cytokinesis

Centromere: a specialized region of a chromosome where sister chromatids are most closely joined to each other

Centrosome: the microtubule-organizing center

Centrioles: cylindrical structures consisting of microtubule triplets, located inside animal centrosomes

cytoplasm divides to form two daughter cells, each with its own nucleus and complete set of organelles

Plants = cell plate

Animals = cleavage furrows

Bacteria = binary fission

Sperm: male reproductive cell

Egg: female reproductive cell

Gametes: reproductive cells such as sperm and eggs

Zygote: fertilized sperm and egg cell

nuclear division that leads to a halving of chromosome number and ultimately to the production of sperm and egg

Diploid: organisms that have two versions of each type of chromosome. They have two alleles of each gene, where one allele is carried on each of the homologs

Haploid: organisms that have cells that contain just one of each type of chromosome, and thus have only one copy of each chromosome with just one allele of each gene

Haploid Number: number of distinct types of chromosomes in a given cell (n)

Ploidy: the number of chromosome sets

Meiosis I: homologs of each chromosome pair to separate so that one homolog goes to one daughter cell, and the second goes to the other daughter cell. Halves the parental chromosomes.

Meiosis II: sister chromatids of each chromosome separate and go to each daughter cell (like mitosis)

1. Early prophase I: chromosomes condense, spindle apparatus forms, nuclear envelope begins to break down, synapsis (pairing) of homologous chromosomes)

2. Late prophase I: chiasmata visible, nuclear envelope broken down

3. Metaphase I: movement of bivalents to metaphase plate is complete

4. Anaphase I: homologs separate and begin moving to opposite poles of the spindle apparatus (sister chromatids stay together)

5. Telophase I: homologs finish moving to opposite poles, spindle apparatus disassembles

6. Prophase II: spindle apparatus reforms

7. Metaphase II: chromosomes are lined up at middle of the spindle apparatus

8. Anaphase II: sister chromatids separate, being moving to opposite poles of the spindle apparatus

9. telophase: daughter chromosomes finish moving to opposite poles, spindle apparatus disassembles