BIOL 102 Study Guide - Midterm Guide: Heat Capacity, Covalent Bond, Hydrogen Bond
Victoria Sa Biology Review Mid Term
1
Introduction
Chapter 1: Evolution and the Themes of
Biology
- The hierarchy of life unfolds as follows;
1) Biosphere
2) Ecosystem
3) Community
4) Population
5) Organism
6) Organ system
7) Organ
8) Tissue
9) Cell
10) Organelle
11) Molecule
12) Atom
- With each step upwards from the atom,
new properties emerge as a result of
interactions among components at the
lower levels
? - In the interrelatedness of levels, how do
different levels of life depend on each
other?
- Energy flows through an ecosystem
o All organisms must perform
work, which requires energy
o Energy from the sun is
converted into chemical energy
by producers, which is then
passed onto consumers
o Chemical bonds are the basis
for energy
- Information is given through stimuli and
also flows through the cells systems
o Perception - Critial, ou a’t
proess ifo if ou a’t
perceive it
o Transduction - Info relay
o Response - Reaction to
information
***The form of biological function suits its
structure and vice versa***
o Understanding the structure of
something helps understand its
function
- The information is in the DNA
o Central dogma
- Every cell in your body has the same
DNA, this is your genome;
o There is one nuclear genome
and one mitochondrial genome
in the typical human cell
o In the plant cell there is also a
chloroplast genome
- The proteome includes all proteins
expressed from your genome
o Certain parts of your DNA code
for specific proteins
- Evolution is an observational fact that
accounts for the unity and diversity of
life
- Mutations are random but natural
selection is not;
o Natural selection is the
mechanism for evolutionary
adaptation of populations to
their environments
o Cells are being selected because
they are strong enough to
mount a defense against their
environment
find more resources at oneclass.com
find more resources at oneclass.com
Victoria Sa Biology Review Mid Term
2
- A scientific theory is a broad in scope,
generates new hypothesis, and is
supported by a large body of evidence
o A theory is not a hunch
o A hypothesis is a well framed
question
Chapter 2: The Chemical Context of Life
- Oxygen, Carbon, Hydrogen and
Nitrogen make up approximately 96%
of living matter
- An atom, the smallest unit of an
element, has the following
components:
o The number of protons
determines the atomic number
o The mass number is the sum of
protons and neutrons
▪ Isotopes differ in
number of neutrons
and therefore mass
o Electron distribution in shells
determines the chemical
behaviour of an atom
- Molecules consist of two or more
covalently bonded atoms
- A hydrogen bond is an attraction
between hydrogen atoms carrying a
positive charge
- Van der Waals interactions occur
between transiently positive and
negative regions of molecules
o Making and breaking bonds are
related to energy transfer
- Molecular Flexibility is of critical
importance
o Hand in glove analogy
o Molecules held together by
single bonds can rotate, double
bonds cannot
- All chemical reactions are theatrically
reversible
- Chemical equilibrium is when forward
and reverse reaction rates are equal
o Cells are far away from
equilibrium because there is no
energy in equilibrium
Chapter 3: Water and Life
- Hydrogen bonds between the negative
oxygen and positive hydrogen in water
molecule are the basis of waters
properties
- Properties of water that contribute to
Earth’s sustaiailit for life;
o Cohesion and Surface Tension /
Adhesion - H-bonds keep water
molecules close to each other
o Specific Heat Capacity - is high
in water which keeps
temperatures steady
o Density - Ice is less dense then
liquid water because of
expansion upon freezing
o Universal Solvent - hydrophilic
substances have an affinity for
water
- A cell cannot be dissolved, however
some molecules in cells can
- Phospholipids are amphipathic
o Both hydrophobic and
hydrophilic
o Their heads and tails have their
specific properties that form
the phospholipid bilayer
- Most cells function at neutrality
o Cells have a pH window
find more resources at oneclass.com
find more resources at oneclass.com
Victoria Sa Biology Review Mid Term
3
- The concentration of H+ is expressed as
pH;
o You can distinguish between
acids and bases with the
presence and absents of H+
o Buffers in biological fluids resist
change on pH
o Regulation of pH in cells takes
up a huge amount of energy
within the cell
Chapter 4: Carbon and the Molecular
Diversity of Life
- Living matter is made mostly of Carbon,
Hydrogen, Oxygen and Nitrogen with
some Sulfur and Phosphorus
- Biological diversity is dependent on
carbons ability to form a huge number
of molecules with particular shapes and
chemical properties
o Carbon has 4 valence electrons,
therefore it can combine with
up to four elements at once
- Variation at the molecular level lies at
the foundation of all biological diversity;
o Length
o Branching
o Double bond position
o Presence of rings
- Functional groups attached to the
carbon skeleton of organic molecules
and participate in chemical reactions or
contribute to function by affecting
molecular structure;
o Hydroxyl group
o Carbonyl group
o Carboxyl group
o Amino group
o Sulfhydryl group
o Phosphate group
o Methyl group
- Isomers are compounds with the same
molecular formula but different
structures and properties;
o Structural isomers - different
covalent arrangements
o Cis-trans isomers - same
covalent bonds but differ in
spatial arrangement
o Enantiomers - mirror images of
each other
▪ The cell has incredible
ability for specificity
and distinguishing these
small differences
- ATP reacts with water forming inorganic
phosphate and ADP
o This reaction releases energy
that can be used by cells
The Chemistry of Life
Chapter 5: The Structure and Function of
Large Biological Molecules
- Macromolecules are polymers built
from monomers
o Monomers form polymers by
dehydration reactions
o They can disassemble by the
reverse process, hydrolysis
Carbohydrates
- Sugars
o Monosaccharides
o Disaccharides
o Polysaccharides
- Composed of CHO
- Base Formula; Cn(H20)n
- Linkages; -H and -OH
find more resources at oneclass.com
find more resources at oneclass.com
Document Summary
The hierarchy of life unfolds as follows: understanding the structure of something helps understand its function. The information is in the dna: central dogma, biosphere, ecosystem, community, population, organism, organ system, organ, tissue, cell, organelle, molecule, atom. With each step upwards from the atom, new properties emerge as a result of interactions among components at the lower levels. Energy flows through an ecosystem: all organisms must perform work, which requires energy, energy from the sun is converted into chemical energy by producers, which is then passed onto consumers. Every cell in your body has the same. Dna, this is your genome: there is one nuclear genome and one mitochondrial genome in the typical human cell. In the plant cell there is also a chloroplast genome. The proteome includes all proteins expressed from your genome: certain parts of your dna code for specific proteins. Evolution is an observational fact that accounts for the unity and diversity of life.
