Bio80 Lecture Exam 1 Study Guide

What are the basic characteristics of life?

DNA, ATP, at least one or more cells, made up of water, cells made of organic molecules, reproduction

Autotroph

Organism capable of producing their own energy

Heterotroph

Organism feeding on other organisms for energy

Asexual reproduction

Process of reproduction involving only one parent organism

Sexual reproduction

Process of reproduction involving two parent organisms

Homeostasis

Ability to regulate and maintain physiological state

Mutation

Alteration of a nucleotide sequence of a gene

Evolution

Change in gene frequency over time

Scientific Method

1. Empirical observation
2. Hypothesis
3. Experiment
4. Data analysis/probability-based conclusion
5. Publication
6. More testing
7. Theory building

What is the purpose of a control in an experiment?

Used to measure effects of variables in an experiment

Hypothesis

a scientifically testable idea

Theory

set of statements based on tested, scientific facts that acts to describe/explain or predict a given phenomenon

Experiment

A set of controlled experiences that may suggest a hypothesis

Empirical

Observations based on the various human senses

Variable

Unstable/changeable factors in an experiment that may influence the outcome

Nature of science in reference to its reliance on probability versus absolute truth, continual testing versus final proof.

Science relies on probability, rather than absolute truth. Experiences must be able to be replicated with the same conclusion.

When was the universe formed?

13.8 bya

When was the Earth formed?

4.5 bya

When did the Earth begin to cool?

3.6 bya

When was the first life on Earth recorded?

3.5 bya

When did multicellular organisms first appear on Earth?

1.6 bya

When did animals appear on Earth?

1 bya - 550 mya

When did plants appear on Earth?

550 mya

When was the Earth colonized by fungi and plants?

500 mya

When was the Earth colonized by land animals?

450 mya

When did humans first appear in their modern form?

250 - 200 tya

Isotope

Atoms of the same element that have a different number of neutrons

Radioactivity

The emission of sub-atomic particles from unstable atomic nuclei

Half-life

time needed for half of a radioactive isotope to decay into a stable isotope

Potassium-argon dating

Measuring ratio of radioactive potassium to argon. Igneous volcano rocks, measures from 100tya-bya

Uranium-lead dating

Measuring the amount of lead-206 daughter isotopes. Igneous rocks, measures from 100mya to 4bya

Carbon dating

Measuring the ratio of carbon-14 to carbon 12. *Can only be used to date organic matter in the last 45,000 years

Oparin-Haldane Hypothesis

Life arose from inorganic molecules, starting from amino acids to create complex polymers

Urey-Miller experiment conclusion

Monomers could be formed from gases given sufficient energy, turning into proteins and other monomers

Where did life on Earth most likely begin?

Deep-sea vents

What type of molecule is believed to be the original genetic material? Why?

RNA; simple molecule with some forms (specifically Ribozymes) acting as enzymes which can replicate itself

Symbiogenesis

Merging of 2 organisms into 1 organism

How does symbiogenesis relate to eukaryotes and prokaryotes?

Asgard Archaens (prokaryotes) consumed proteobacteria and utilized them as the first mitochondria. They also consumed cyanobacteria to use them as a chloroplast.

Fimbraie

Used by prokaryotes to stick to surfaces

Plasmids

Rings of additional DNA in prokaryote cells that may code for specific proteins

Cell wall (prokaryote)

Peptidoglycan wall used to provide structure to cell

Pili (prokaryote)

Used by prokaryotes to attach to other bacteria

Endospore (prokaryote)

Desiccated pack of DNA

Flagellum (prokaroyte)

Whip like tail used for movement

Capsule (prokaryote)

Sticky slime layer made of short-chain polysaccharides

Cytoplasm (prokaryote)

Liquid contained within prokaryote cell, consists of mostly water, salts, organic molecules

Plasma membrane (prokaryote)

Separates cell interior from outside environment

Nucleoid region (prokaryote)

Area within prokaryote cell where most of cell's DNA is located (not membranous)

Binary fission

A form of asexual reproduction in single-celled organisms by which one cell divides into two cells of the same size

Transformation

Modification of a cell or bacterium by the uptake and incorporation of exogenous DNA

Transduction

Process which DNA Is transferred from one bacterium to another through virus

Conjugation

DNA is transferred from one bacterium to another through direct contact

What is the use of a pilus during conjugation?

Connects cells together

What is the "f-factor" in conjugation?

DNA sequence transferred from one cell to another during conjugation (fertility factor)

Purpose of a relaxosome in conjugation

Complex protein that regulates the t-DNA transfer during conjugation

Transferosome

Protein assemblage forming a pore connecting the membranes of two conjugational bacteria

Obligate anaerobe

Organisms that can perform fermentation (anaerobic) respiration only - NO3^- and SO4^2-

Obligate aerobe

Organisms that require O2 for aerobic respiration

Facultive anaerobe

Organisms that perform aerobic respiration in the presence of O2, fermentation if O2 is not available

Chemilithoautotrophy

Organisms that obtain energy by consuming inorganic compounds

Nitrogen fixation

Atmospheric nitrogen is converted into ammonia by specific bacteria

Heterocyst

Cyanobacterial cell that allows for nitrogen fixation

What bacterial group is responsible for the Oxygen Crisis?

Cyanobacteria

Which bacterial group led to the eukaryotic mitochondria?

Proteobacteria

Which bacterial group led to the eukaryotic choloroplast?

Cyanobacteria

Which bacterial group is responsible for the most human sexually transmitted disease?

Chlamydias

Extremophile

Organisms living in extreme conditions

Halophile

Saline-loving organisms

Thermophile

Heat loving organisms

Psychrophile

Cold loving organisms

Acidophile

Acid loving organisms

Alkalophile

Alkaline loving organisms

Methanogen

Anaerobic organisms that produce methane through metabolism

Substrate

Surface an organism lives on

Desiccation

Drying out; dehydration

Producer

Organisms that are able to produce their own food

Decomposer

Organisms that feed on decaying organic matter for energy

Pathogen

An organism causing disease to its host

Mutualist

Long term ecological relationship between two or more organisms that benefit

Symbiont

Organism that interacts with another organism long-term

Host

Larger organism harboring another smaller organism

Diploid

Containing two sets of DNA, 1 from each parent

Haploid

Containing one set of DNA molecules

Monad

DNA molecule in its single, unreplicated state

Dyad

DNA molecule in its replicated state

Tetrad

Group of 4 chromatids in the prophase of meiosis

Homologous pair

DNA molecules of same shape & size, coding for similar polypeptide

Mitosis

Haploid cells are reproduced through mitosis, cell splits into identical cell (asexual process)

Meiosis

Diploid cells are reproduced through meiosis, utilizing gametes (reproductive cells) from each parent to produce non-identical cells

What is the structural and functional purpose of a gene?

Structurally, genes encode for physical structures of an organism's cells. Functionally, genes serve as a unit of heredity, determining an offspring's physical features based on the protein information within the genes

Nucleus

Part of cell that houses DNA of an organism

Ribosome

Part of cell that conducts protein synthesis

Mitochondrion

Part of cell responsible for ATP production through cellular respiration

Food vacuole

Part of cell that digests food matter into nutrients

Cilia

Tiny hairs on cell that allows for locomotion

Flagella

Whip-like tail on organism that allows for motion

Cytoplasm

Fluid inside cell

Plasma membrane

Separates cell interior from outside environments

Chloroplast

Organelle that captures light energy and converts into chemical energy through photosynthesis

Cell wall

Provides structural support for cell