bio 1st semester

Big Bang

13.7 billion years ago - formed Universe

Nebula Theory

5 billion years ago - formed Sun and solar system

Accretion

4.6 billion years ago - formed Earth

Cooling of the Earth

4 billion years ago - formed oceans

First living thing on our planet (bacteria)

3.8 billion years ago (simple cell prokaryotes)

Photosynthetic Bacteria (cyanobacteria)

3 billion years ago

The Endosymbiotic Theory

1.5 billion years ago (multicellular)

Making of Eukaryotic cells

1.5-2 billion years ago

Multicellular life

1 billion years ago

Mammals

200 million years ago (Mesozoic)

Death of Dinosaurs

65 million years ago (KT extinction)

Neanderthal dies

25,000 years ago

Humans

200,000 years ago (Cenozoic)

The #1 evidence for the Big Bang

Cosmic Background Microwave Radiation

Accretion

The process of growth or increase, typically by the gradual accumulation of additional layers or matter

The compound of water came to the Earth in two ways

Meteorites and comets

Early atmosphere was toxic, some compounds present were

Carbon monoxide, Hydrogen sulfide, and Hydrogen Cyanide

Denser elements are lower in the Earth

Crust > Mantle > Core

Plate Tectonics

The Earth's crust is broken into pieces we call plates and they move.

Convergent

Plates moving towards each other

Divergent

Plates pulling apart

Transform

Plates sliding past each other

Unicellular

Single cell

Anaerobic respiration

Respiration without oxygen

Aerobic respiration

Respiration with oxygen

Prokaryotic

Cells without nucleus; bacteria

Eukaryotic

Cell with a nucleus and small organs called organelles; Animals, plants, fungi, protista

Prokaryotic

Always unicellular

Eukaryotic

Often multi-celled organisms

The Endosymbiotic Theory

Proposes that eukaryotic cells arose from living communities formed by prokaryotic organism communities

Earth's history is broken into 2 geological categories

1. Eras 2. Periods

4 Eras

1. Pre-Cambrian (oldest) 2. Paleozoic 3. Mesozoic (age of reptiles and dinosaurs) 4. Cenozoic (youngest and age of mammals)

Mammals

Warm-blooded, give live birth, homeostasis, and have body hair

Extinction toward the end of Pre-cambrian time caused by excessive oxygen in the atmosphere

Killed off most prokaryotes: Cyanobacteria/Oxidation crisis

Greatest extinction in the history of our planet due to the formation of Pangea End of Paleozoic Era

Permian extinction

Complex Cells/Eukaryotes

1.5-2 billion years ago

Extinction caused by meteorite impact at the end of the Mesozoic era

K-T extinction

Why is mass extinction good and what % of living things have gone extinct?

Mass extinction is good because it provides ecological opportunities for weaker species. More than 99% of living things have gone extinct

Oldest era

Pre-Cambrian

2nd era

Paleozoic

3rd era

Mesozoic

Youngest Era

Cenozoic

3 gases in today’s atmosphere

Nitrogen, Oxygen, Carbon Dioxide

Fossil

The remains of a once living thing

Fossil record

All information about past life

What are the steps to becoming a fossil?

1. Organism Dies

2. Covered quickly

3. Becomes fossilized

What type of rock?

sedimentary

Fossil Record cont.

The fossil record provides evidence about the history of life on Earth. It also shows how different groups of organisms, including species, have changed over time. (Over 99% of all species that have lived on Earth have gone extinct)

Dating fossils (determining the age of fossils) using:

1. Relative dating

2. Radioactive dating

Relative dating

The age of a fossil is determined by comparing its placement with that of fossils in other layers of the rock. (index fossil)

Radioactive dating

Scientists use radioactive decay to assign an absolute age to rocks. Some elements are radioactive and steadily break down into non radioactive elements.

Radioactive dating is the use of?

half-lives to determine the age of a sample

Half-life

the length of time required for half of the radioactive atoms in a sample to decay into daughter atoms and parent atoms.

Isotope

an atom of an element with the same number of protons but different numbers of neutrons

What do protons define?

Protons define the element

All life depends on 4 macromolecules which are:

Carbohydrates, lipids, proteins, and nucleic acids

Mono-

one

Di-

two

Poly-

3 or more (many)

Monomer

Basic unit

Polymer

3 or more monomers

Polymerization

The process by which monomers join together to form a polymer

Protein’s monomer

monopeptide (1 amino acid)

Protein’s polymer

polypeptide (many amino acid)

Protein’s job/purpose

Control the rate of reactions, effect development, help form muscles and bones, transport substances, and fight disease (enzymes are protein)

Food with protein

Animal products, nuts/seeds, beans, plants (minimally)

Nucleic acids monomer

Nucleotide

Nucleic acids polymer

Deoxyribonucleic Acid (DNA), Ribonucleic Acid (RNA)

Nucleic acids job/purpose

Store and transmit genetic information

Nucleic acids food

Anytime you eat a once living thing, you are eating DNA

Carbohydrate monomer

monosaccharide (1 sugar)

Carbohydrate polymer

polysaccharide (many sugars)

Carbohydrate jobs/purpose

provide the body with glucose, which is converted to energy used to support bodily functions and physical activity.

Carbohydrate food

fruit = fructose, milk = lactose, candy = sucrose, plant structure = cellulose

Lipid subunits

Glycerol, fatty acid

Lipid saturated

Saturated fat (from animals) solid at room temp

Lipids unsaturated

unsaturated fat (from plants) liquid at room temp

Lipids common categories

fats, oils, waxes, and steroids

Lipids job/purpose

store energy, chemical messengers, and biological membranes

Open system

moving in 1 direction

Closed system

recycle

Sunlight/energy is a _ system

open

Carbon cycle and nutrients are _ systems

closed

Why is carbon important for all living things?

Carbon is the backbone of all organic molecules

How does the Industrial Revolution deal with the Carbon Cycle?

During the Industrial Revolution, they burned a large amount of fossil fuels, putting Carbon into the atmosphere.

There are _ carbon stores

7

There are _ carbon processes

11

Atmosphere→

Air

Lithosphere→

Land

Hydrosphere→

Water

Biosphere→

Living things

Carbon Stores/Reservoirs

store carbon

Carbon processes

how carbon goes through the cycle

Source

puts out more carbon than it takes in (output)

Sink

takes in more carbon than it puts out (input)

How is carbon stored underground

in the form of coal, oil, and gas

When there is too much carbon in the atmosphere

the heat from the sun is trapped causing global warming/climate change

How are fossil fuels created

over thousands of years of being compressed underground

Burning fossil fuels produces carbon by..

the process of combustion

Carbon in the atmosphere mostly consists of

CO2 (carbon dioxide)