Chapter 1.1

Key

❣ = organisms

❤ = molecule

⭐ = principle

⬛ = DNA / genetic info

◇ = Energy

△ = plants

$ = living/life

❄= Cell

💧= Photosynthesis

🌜= Proteins

Chapter 1 (p1)

⭐ All $ ❣ need ◇ to grow, move, reproduce, and maintain bodies → this explains why △ are green (chloroplast)

Most ◇ comes from sun

△ leaves have chlorophyll → capture sun ◇

◇ used to turn H₂O + CO₂ → sugar + O₂ (💧)

Sugar stores ◇ in chem bonds. ❣ that eat △ get ◇ by breaking sugar

Other ❣ get ◇ from ❤ in bodies of ❣ they eat

$ ❣ are solar-powered.

⭐ $ ❣ survive & thrive by interacting in complex ways

❣ come in all sizes

Lichens- interactions fungi & 💧 ❣ → depend on each other to survive

❣ too small to see are still imp for system to function

Chapter 1.1 (p2)

Biology- study of $/❣.

All $ has 1 origin/common ancestor (single ❄).

Shared characteristics of $:

Made of common chem parts (nucleic acids - ⬛(most imp ❤), amino acids - make 🌜, & ❄ in membranes).

$ depends on complex parts working together in detailed ways.

Has ⬛ that uses almost same code to build 🌜.

Change env. ❤ into new $ ❤.

Take ◇ from env. & use for $ functions (walking etc.).

Copy ⬛ same way when reproducing.

Important genes similar in way made

Evolved through small ⬛ changes.

All $ = common ancestor, diverse ❣ from one $ form.

Not all $ has every trait at all times:

Seeds - $ but don’t always use ◇ or reproduce.

Viruses - not made of ❄, can’t function alone. They use ❄ to mutate & work. But viruses have ⬛ & evolve. Evid shows viruses came from ❄ $ means part of $.

$ development linked w/ physical & chem processes.

Earth formed 4.5–4.6 bil yrs ago.

~600 mil yrs later → $ evolved.

Earth climate before dif.

Nucleic Acids imp in evolution → multiply & store info to make 🌜.

🌜 → diverse shapes, multiply, & trigger chem reactions.

Next step in origin of $ - membrane formed → kept 🌜 & other bio ❤ separate from outside- form ❄

Fatty acids imp- make film membranes (don’t dissolve in water).

When agitated, films form hollow spheres → could keep bio ❤ inside.

Having inside vs. outside → chem reactions concentrated (could be combined & controlled)

Natural process of membrane formation → led to 1st ❄ → could reproduce → evolution of 1st cellular ❣

~2 bil yrs after ❄ origin - only 1-❄ ❣ (prokaryotes)

Have ⬛ & bio structures

Survive harsh envir.

$ only in ocean (❤ for ◇ & shield from UV cuz little O₂ = no ozone in atmos.)

Similar to descendants - bacteria

💧 - get sun ◇

Prok. break envir. ❤ → release/use ◇ in chem bonds (still do today)

~2.7 bil yrs ago 💧 appears

Sun ◇ → chem bond ◇ (glucose & bio ❤)

Chem. bonds ◇ power ❄ reactions (Ex. make 🌜)

Basis of most ❣ - food source for others

💧 ❣ use sun ◇ to build tissue → food for others

cyanobacteria 1st 💧 ❣

Make O₂ → poison to many prok. (weak die, strong survive → O₂ builds up)

Aerobic metabolism = use O₂, release more ◇, better

Anaerobic metabolism = release ◇ w/out O₂

O₂ → ❣ $ more intensely & grow bigger

Most ❣ use O₂ to release ◇ from ❤

~500 mil yrs ago → Ozone absorbs enough UV for ❣ to live on land

1st Organelles - separate ❄ functions

1st appear ~2.5 bil yrs after $ appeared

Nucleus (has ⬛) gives eukaryotes its name (reg prok. no nucleus)

Endosymbiosis - ❣ lives inside another

Mitochondria (release ◇) → evolved from eating prok.

Chloroplast (does 💧) → evolved from eating 💧. prok.

When ❣ can’t break down prok. - Partnership: prok. made sugar & host gives safe env.

Early $ - all single ❄

Some eukaryotes ❄ didn’t separate → grouped → specialization (ex: reproduction, absorb nutrients)

❄ specialization → multicellular, larger, efficient, adapted

Reproduction - genome (sum of ⬛) replicate

Mutations (changes in ❣) - common

Spread in species → accumulate → species split (no interbreeding) = new species

Binomial (scientific name for species)

1st word - genus (recent common ancestor)

2nd word - species

Ex. Homo(homo neanderthalensis) sapiens(wise)

Biology mostly comparing species

Genome sequencing - order of nucleotides (DNA’s building blocks) →molecular evid.

Molecular Evid.→ supports fossil record

Phylogenetic trees(tree of life) - evolutionary relationships

Tree of Life:

Branches - evidence from fossils, structures, chemistry, genomes

Molecular data → 3 domains: Archaea, Bacteria, Eukarya (each evolves separately)

No living species evolves from another living species today.

Ex: humans ≠ chimpanzees, both share extinct common ancestor

Archaea & Bacteria - single-celled prok.

Do dif. - separated early

Eukarya - eukaryotic cells

Mitochondria & chloroplasts → came from endosymbiosis with bacteria

Multicellular Eukaryotes - plants, fungi, animals (close related to unicellular Eukaryotes(protists))

Multicellularity originated by itself

Knowledge from one organism can be linked with another cuz all life related by common ancestor, shared genetic code, and has similar DNA

Ex. Use model organisms for research cuz can extend to other organisms