Biology 1202 exam 1

fossil record

- discovery of bones from many different dino species - transitional forms that link whales with land-dwelling ancestors that are now extinct

observation of natural selection in action

-development of pesticide resistance in insects -changes in average beak sizes in finches following wet or dry years

anatomical and molecular homologies

-similar forearm anatomy in different species of mammals -same genetic language of DNA and similar genes in yeasts, fruit flies, and humans

In a DNA double helix an adenine of one strand always pairs with a(n) _____ of the complementary strand, and a guanine of one strand always pairs with a(n) _____ of the complementary strand. a. cytosine ... uracil b. uracil ... cytosine c. cytosine ... thymine d. guanine ... adenine e. thymine ... cytosine

e. thymine ... cytosine

What are the main components of a nucleotide?

phosphate, sugar, nitrogen base

The four stage hypothesis for the origins of life

Small molecules were made (amino acids, nucleotides) Small molecules joined to form larger molecules (proteins, nucleic acids) Pre-cells (protobionts) formed as droplets with membranes surrounding molecules Self-replicating molecules get trapped inside protobiont, forming "pre-cell"

Stabilizing selection

favors intermediate phenotypes, selecting against phenotypes at both ends of a range and reducing variation.

disruptive selection

favors phenotypes at both ends of a range over intermediate phenotypes. This type of selection may occur when the habitat is varied.

directional selection

favors phenotypes at one end of a range and is common in periods of environmental change.

In a type of sexual selection often called _______, individuals of one sex (usually females) are choosy in selecting their mates. This choice is often based on the showy appearance or behavior of the male.

mate choice

histones

proteins that help bind DNA

basic science

seeking fundamental or new knowledge

In sexual selection, individuals with certain inherited characteristics are more likely to obtain mates than other individuals. This often results in ________, differences between the sexes in size, appearance, and behavior.

sexual dimorphism

chromosome

super condensed DNA that is ready to be replicated

applied science

taking knowledge and applying it to solve problems, adheres to an established and well recognized scientific method

biogeography

-resemblance of island species to nearby mainland species -unique collection of marsupial mammals in australia

DNA

A complex molecule containing the genetic information that makes up the chromosomes. which is made of nucleotides- sugar, nitrogen base, and phosphate group

pseudoscience

A fake or false science that makes claims based on little or no scientific evidence. essential oils, astrology, crystal healing

Which of the following events occurs during transcription? a. A molecule of RNA is formed based on the sequence of nucleotides in DNA. b. The message in mRNA is translated into a protein. c. mRNA binds to a ribosome in the cytoplasm. d. Those segments of the RNA strand that do not actually code for the protein are removed. e. A cap is added to the RNA molecule.

a. A molecule of RNA is formed based on the sequence of nucleotides in DNA

Within the nucleus of the cell, DNA must be compacted and organized. How is this accomplished? a. DNA is coiled around special histone proteins to form nucleosomes. Nucleosomes are coiled further into strands called chromatin. b. DNA is wound around histone proteins to form structures called chromosomes. Each chromosome is held in place within the nucleus of a cell by a structure called a nucleosome. c. DNA is coiled in a spiral and folded back and forth within the nucleus. It is held in place by special fibers called chromatin. d. DNA is wound around special proteins called nucleosomes to form chromatin. Chromatin is coiled further into long strands called chromosomes.

a. DNA is coiled around special histone proteins to form nucleosomes. Nucleosomes are coiled further into strands called chromatin.

Which of these pathogens has the highest percentage of antibiotic-resistant strains? a. Neisseria gonorrhaea b. Salmonella c. Campylobacter d. Streptococcus pneumoniae

a. Neisseria gonorrhaea

If a strand of DNA reads "AGG TAC GGG CTA", what will the complementary mRNA strand read? a. UCC AUG CCC GAU b. AGG TAC GGG CTA c. AGG UAC GGG CUA d. TCC ATG CCC GAT

a. UCC AUG CCC GAU

A DNA strand is often referred to as a polynucleotide. What is a polynucleotide? a. a chain of nucleotides b. a chain of sugars c. an individual nucleotide d. a chain of bases e. an individual base

a. a chain of nucleotides

According to one of the main hypotheses for the origin of life, what must have come first?

abiotic synthesis of organic monomers

In a species of snail, dark-shelled individuals are better hidden from bird predators in the shady forest, while light-shelled individuals are better hidden in well-lit brushy edge areas. If there were no areas of intermediate brightness in this habitat,which type of selection would act on shell color in these snails? a. Directional selection b. Disruptive selection c. Stabilizing selection

b. disruptive selection

The original source of genetic variation that serves as the raw material for evolution is ________. a. gene flow b. mutation c. geographic isolation d. random fertilization

b. mutation

nucleosomes

bundles of DNA and histones

Small lizards have difficulty defending their territory, but large lizards are more likely to be preyed upon by owls. Which type of selection would act on body size in these lizards under these conditions? a. Directional selection b. Disruptive selection c. Stabilizing selection

c. stabilizing selection

chromatin

condensed DNA that is coiled into a bundle

Which of these is a difference between a DNA and an RNA molecule? a. DNA is a polymer composed of nucleotides, whereas RNA is a polymer composed of nucleic acids. b. DNA contains uracil, whereas RNA contains thymine. c. DNA contains nitrogenous bases, whereas RNA contains phosphate groups. d. DNA is double-stranded, whereas RNA is single-stranded. e. DNA contains five-carbon sugars, whereas RNA contains six-carbon sugars.

d. DNA is double-stranded, whereas RNA is single-stranded

What is the relationship between DNA, genes, and proteins? a. DNA is coiled into structures called genes and bound together by special proteins. b. DNA "reads" the genes within your nucleus and translates them into proteins. c. Genes are composed of proteins and DNA makes those proteins. d. Genes are specific sections of DNA that code for different proteins.

d. Genes are specific sections of DNA that code for different proteins.

In evolutionary terms, an organism's fitness is measured by its __________. A. mutation rate b. genetic variability c. health d. contribution to the gene pool of the next generation

d. contribution to the gene pool of the next generation

Imagine that a new population of humans is established on a previously uninhabited planet from ten randomly selected people in your biology class. Over thousands of years, the descendants of those ten people reproduce and prosper, but they do not reflect well the diversity of humans on Earth. This reduction in genetic diversity in the establishment of the population is an example of __________. a. gene flow b. the bottleneck effect c. genetic drift d. the founder effect

d. founder effect

Protein synthesis has two parts to it. During the second part, a. polypeptides are folded into their final shapes and packaged for shipment outside of the cell. b. mRNA is processed with the addition of a cap and a tail. c. an mRNA copy is made from a segment of DNA within the nucleus. d. ribosomes use the sequence of nucleotides found on the mRNA strand to recruit amino acids, binding them together into a polypeptide chain (ie-protein).

d. ribosomes use the sequence of nucleotides found on the mRNA strand to recruit amino acids, binding them together into a polypeptide chain (ie-protein).

Which of these pathogens causes the highest number of antibiotic-resistant infections per year? a. Neisseria gonorrhaea b. Salmonella c. Campylobacter d. Streptococcus pneumoniae

d. streptococcus pnemoniae

Protein synthesis has two parts to it. During the first part, an mRNA copy is made from a segment of DNA within the nucleus. This process is called _____. a. adjudication b. mRNA processing c. translation d. transcription e. replication

d. transcription

In a nucleotide, the nitrogenous base is attached to the sugar's _____ carbon and the phosphate group is attached to the sugar's _____ carbon. a. 2' ... 3' b. 1' ... 2' c. 2' ... 1' d. 1' ... 3' e. 1' ... 5'

e. 1' ... 5'

hypothesis

explanation for something happening- must be testable