Biology
Study Guide
Gucciardo/ Schwartz /CJ
Semester 2
Heredity
Heredity
 The passing of characteristics or traits from
parents to offspring
DOMINANT
 THE EXPRESSED FORM OF A TRAIT
 REPRESENTED BY CAPITAL LETTERS
 EXAMPLE: PURPLE FLOWER = B
recessive
 the trait not expressed in an offspring
 represented by lower case letters
 example: white flower = b
Homozygous
 Two alleles of a particular gene that are the same
 Example: BB or bb
Heterozygous
 Two alleles of a particular gene that are different
 Example: Bb
Genotype
 The set of alleles that an individual has for a character or trait
 Example: (three possible types) BB, bb, or Bb
Phenotype
 The physical appearance of any given character or trait
 Example: Purple flower or white flower
Punnett Square: (each square = 25% of the offspring)
Genotype:
50% Tt , 50% tt
Phenotype:
50% tall, 50% short
Practice…
2
Multiple Alleles
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More than two alleles exist for a trait.
Example: Blood type exists as four possible phenotypes: A, B, AB, & O
GENOTYPES
IAIA
IAi
IB IB
IB i
IAIB
ii
RESULTING PHENOTYPES
Type A
Type A
Type B
Type B
Type AB
Type O
Pedigree Studies
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Each generation is represented by a roman numeral
Each person is numbered
Males are squares
Females are circles
Affected individuals are shaded
3
Evolution
 change over time
 fossils show that evolution happens
gradually

homologous (similar) skeletal structures
suggests common ancestors
Darwin’s Journey
 South America to Galapagos Islands
 found animals on the islands resembled those living on the coast
of South America
Natural Selection
 individuals that have traits that are better suited to their
environment are more likely to survive and reproduce more
successfully
Adaptation
 a change in a species that makes it better suited to its
environment (like the giraffe’s neck)
Prokaryote
 organism consisting of a single cell (like bacteria)
 1st living things to appear on earth
Eukaryote
 an organism made up of many cells
 includes animals, plants, and fungi
Photosynthetic
 gathers light from the sun and converts it to energy
Heterotrophic
 eats other organisms for energy
Competition
 happens when resources are limited
4
Linnaeus, Carl
 father of taxonomy (naming and classifying organisms)
 started system called binomial nomenclature
 consists of: Genus species
Example: Homo sapien (human)
 two word name for a species is called its scientific name
 the scientific naming system allows all biologists to
communicate regardless of the language they speak
Domain
 largest division that a group of animals can belong to
Organization:
Kingdom, Phylum, Class, Order, Family, Genus, Species
(Kings play chess on Friday generally speaking)
least in common (simple)------------------------------------------- most in common (complex)
largest group
smallest group
6 Kingdoms
Animalia
eukaryotes
- multicellular
- heterotrophic
- cells without walls
Plantae
eukaryotes
- autotrophic
(photosynthesis)
- producers
Eubacteria
prokaryotes
- found everywhere
- the kind people are most
familiar with
Fungi
eukaryotes
- decomposers
Protista
eukaryotes
-most diverse kingdom
-found anywhere there is water
-animal-like protista move like
animals
Archaebacteria
prokaryotes
- most unicellular
Paramecium
5
Bacteria
Two major groups:
 Archaebacteria “ancient bacteria”
 Eubacteria “true bacteria”
smaller than eukaryotic cells
In 1928, Alexander Fleming discovered a fungus that killed bacteria. By accident,
he left Petri plates out and mold grew on the surface, leaving a ring where bacteria
were killed. He later called the secretion penicillin, the first antibiotic.
Viruses


parasitic
active inside living cells
Pathogen
 a virus, microorganism, or other substance that causes
disease
Vaccine
 harmless version of a virus injected into the body that
produces immunity
 sometimes the vaccine can cause the disease
6
Animalia
Invertebrates
-animals that do not have a spine or backbone
-includes arthropods, echinoderms, mollusks, annelids, nematodes, playhelminthes
Phylum: Annelids – earthworms, leeches
 Coelomate – has a coelom (fluid filled body cavity)
 1st segmented animals
Phylum: Platyhelminthes – flatworms
 Acoelmate – does not have a coelom
 Cephalization – evolutionary trend where sensory
structures gather in the anterior end, eventually
producing a head with sensory organs
Phylum: Nematodes – roundworms
 Some are hermaphrodites, producing both eggs and sperm
Phylum: Arthropods – insects, arachnids, lobsters, crayfish, crabs
 Two-thirds of all name species
 Segmented bodies
 Jointed appendages
 Bilaterally symmetrical
 Covered by a hard exoskeleton
 Grow by shedding or molting
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Phylum: Echinoderms – sand dollars, sea stars, sea urchins
 1st to develop a endoskeleton
 Coelomate - has a coelom
 Radial symmetry
Phylum: Cnidarians – jellyfish, corals, hydras, sea anemones
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Radially symmetric
Carry stinging organelles called
nematocysts
Phylum: Mollusks – octopus, squid, snails, bivalves (clams, oysters, scallops)
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Coelomate - has a coelom
Has nephridia which are small tubes that collect and release waste from the body
All have an open circulatory system except the octopus and squid
Vertebrates
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Have a backbone that protects dorsal nerve cord
1st to ever evolve were fish
All evolved in water, were carnivores, and had skeletons
All have bilateral symmetry
Marsupial
-live birth
-baby completes
development in
in pouch
Cartilaginous Fishes
Placental
-live birth, baby completely developed
-placenta carries nutrition and removes waste
8

skeletons made of cartilage
Examples:
 sharks, rays, skates
Bony Fishes
Class of Animals
Reptilia: turtles, snakes, crocodiles
 scaly skin
 lay their eggs on
land
Amphibia: frogs, salamanders
 can live on land or
water
 moist skin
 lay their eggs in
water or in moist
environments
Aves: birds
Mammalia: dolphins, manatees, humans
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
endothermic
thin hollow bones

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rely on parental care for protection,
knowledge, and food
hair provides insulation, protection, and
sensory information
9
Bodily Systems
Excretory System
Removes waste from the body
Digestive System
how bodies process food
Respiratory System
Circulatory System
the system of organs and
tissues, including the
heart, blood, blood vessels,
and lymph glands,
involved in circulating
oxygen and nutrients
throughout the body.
Skeleton
The bones,
cartilage, and joints
that support and
protect the body
Nervous system
the system of nerves and nerve centers in an
animal or human, including the brain, spinal
cord, nerves,
and ganglia.
10
DNA
Watson and Crick
 discovered the structure of DNA
Chargaff’s rule:
The amount of Adenine
equals the amount of
Thymine. The amount of
Guanine equals the
amount of Cytosine.
(Nitrogen bases)
Nucleotide
 a sugar, a phosphate group, and a
nitrogen base
Deoxyribose
 five carbon sugar in nucleotides
Gel electrophoresis separates DNA fragments by their size and shape.
DNA fingerprinting or analysis allows investigators of crime scenes to look at
different body cells from different individuals, who are unlikely to have the same
DNA.