100% satisfaction guarantee Immediately available after payment Both online and in PDF No strings attached
logo-home
Biol 151 Exam 1 Summary $10.99   Add to cart

Summary

Biol 151 Exam 1 Summary

 4 views  0 purchase

This is a comprehensive and detailed summary on exam 1 for Biol 151. *Essential for effective study!! *For you, at a price that's fair enough!!

Preview 2 out of 15  pages

  • September 4, 2024
  • 15
  • 2020/2021
  • Summary
All documents for this subject (6)
avatar-seller
anyiamgeorge19
Bio 151 Study Guide #1
Introduction to Life
 Earth has been around for a hecking long time - 4.5 billion years
o First true cells = prokaryotes from 3.9 billion years ago
o Has water – important for life, required for life to exist
 Early Earth was too hot for liquid water, it had to cool down first
 Ice = potential for life
 Came from icy comets
 New life followed water
o Earliest cells = fossils found in Australia from 3.5 billion years ago
 Similar to cyanobacteria – photosynthetic organism
 Prokaryotic, small and simple – no complex parts
 Able to live in hostile environment
 Larger cells came 500 million years ago, plants and animals
o Humanoids came 2.5 million years ago
o Anatomically modern humans – 200,000 years ago
 Life – things all living things have in common
o Cells
o Adaptation
o Reproduce
o Organized
o Growth
o Metabolism
o Homeostasis
o Response to Stimuli
 Order + Cells
o All life organized on inside
 Specific to carry out jobs
o All life consist of one or more cells
 Atoms  molecules  cells  organelles
 Amoebas are single-celled
 Bigger things consist of many cells
 Specialized
 Form stuff like tissue  organs  organ systems
o Failure of organization = bad
 Response to stimuli
o Stimulus: Anything the organism can detect and respond to
o Organisms sense surroundings, responds accordingly
 Ex: Venus fly trap
 Reproduction
o Single cells just divide and make identical copies (same DNA)
 Mitosis
 Makes a copy of the DNA
 One cell splits into two identical cells
 Variation comes from mutations
o Multi-celled  sexual reproduction
 Involves the passing down of DNA from parent to offspring
 Offspring are similar (but not identical) to parents
 Combining parent’s DNA
 Diverse offspring  allows species to evolve more
 Genetic diversity = required for evolution
 Adaptation – organisms are well adapted to their environment due to natural selection
o Some traits  more common because allows organism to thrive in environment
 Growth and Development - Organisms grow & develop according to their genes
o Genes – recipe for proteins  makes everything
 Gene: Segment of DNA containing information for a protein
 Provides instructions for each species’ unique traits
o Most individuals share traits within a species
 Homeostasis: Steady state internally so everything functions properly
o Maintaining constant internal conditions

, o Organisms evolved to maintain homeostasis in certain environments
 Ex: Temp, pH, concentration of chemicals
 Not all organisms regulate body temperature
 Ex: Camels with humps, polar bears, panda bears
 Not always beneficial if environment is rapidly changing
 Energy – needed for metabolic processes
o Attained from eating or photosynthesis (sun)
o Various chemical processes taking place in cells of organism
 Adaptation + Energy - Making use of food available
o Ex: Koalas and eucalyptus leaves, anteater and ants, sloth and leaves
o Digestive system – determines what can be digested and how efficiently
o Behavior – ways to get food
o Anatomical Structures
 Ex: Anteater and nose
o Metabolism - How much energy you could use
 If the energy supply is limited, metabolic reactions proceed more slowly

Atoms, Bonds, and Water
 Everything is made of atoms
o Atoms: Tiny particles that consists of protons, neutrons, and electrons
o 3 Main particles
 Protons = +1, weighs 1
 Neutrons = 0, weighs 1
 Electrons = -1, weighs essentially nothing
o Most of an atom’s volume is empty space
 Nucleus = size of a pea
 Particles gives characteristics to an atom
o Protons determine atom identity
o Electrons determine bonding behavior – interaction with other atoms
 Bond types – sharing or taking electrons
o Neutrons affect mass, no effect on identity
 Element: Substance made of one atom type
o 94 = naturally occurring, 25 = made in lab
o Organized on periodic table based on atomic number (protons)
 Electron number = same as proton number
 No +/- = neutral
 Can figure out number of neutrons from mass  subtract mass from protons
 Decimal point – due to variation in neutron number depending on element
o Has different properties - chemical and physical
 Working with CHNOPS – makes up 96% of mass of all living organisms
 Neutrons determine mass
o Atomic mass: Number of protons + neutrons
o Proton number will be smaller than atomic mass
 Isotope: Atom with different neutron number
o Essentially the same but different mass
o Ex: Carbon
 Used to track things
o Radioisotope: Unstable (radioactive) isotopes
 Used for carbon dating – older fossils have different carbon makeups
 Electrons are found in orbitals outside nucleus
o Orbitals: Regions around nucleus where we expect to find electrons
 Each orbital holds 2 electrons
 Can have various shapes
o Bigger atoms have more electrons, fills more orbitals
o Columns in periodic table based on orbitals
o Fill orbital in sequence, moving farther away from the nucleus
 Located at different distances from nucleus
 First shell fits 2
 Second fits 8
 3rd shell and beyond fits 8 – doesn’t really matter in bio

The benefits of buying summaries with Stuvia:

Guaranteed quality through customer reviews

Guaranteed quality through customer reviews

Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.

Quick and easy check-out

Quick and easy check-out

You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.

Focus on what matters

Focus on what matters

Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!

Frequently asked questions

What do I get when I buy this document?

You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.

Satisfaction guarantee: how does it work?

Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.

Who am I buying these notes from?

Stuvia is a marketplace, so you are not buying this document from us, but from seller anyiamgeorge19. Stuvia facilitates payment to the seller.

Will I be stuck with a subscription?

No, you only buy these notes for $10.99. You're not tied to anything after your purchase.

Can Stuvia be trusted?

4.6 stars on Google & Trustpilot (+1000 reviews)

83637 documents were sold in the last 30 days

Founded in 2010, the go-to place to buy study notes for 14 years now

Start selling
$10.99
  • (0)
  Add to cart