Download Life Science 2nd Semester Exam Review

Life Science
nd
2 Semester Exam Review
Basic Concepts
Structure of Ecosystems/Levels
of Organization
• Organism – individual living (biotic) thing
• Population – group of organisms, all of one
species, which live in the same place and the
same time
• Community – all the populations of different
species, same place, same time
• Ecosystem – Populations of plant and animals
that interact with each other in a given area
and with the abiotic parts (non-living)
• Biosphere – The portion of Earth that
supports life
Has
Nucleus
Ribosomes
and DNA
No Nuclear
Membrane
Cell Structure
Cell Structures
• 1. Cell wall: rigid layer of
nonliving material that
surrounds the cells of plants
– Made of cellulose
– Protects and supports the cells
• 2. Cell membrane: Boundary
that protects the cell from
the environment & controls
what comes in and out
– All cells have
– Like a screen door
3. Nucleus: control center for the
cell
4. Ribosomes: grain like bodies
on the ER & in the cytoplasm
5.Endoplasmic Reticulum: (called ER) carry
proteins and materials within the cell
6. Golgi Body: receives and packages
proteins from ER and distributes
around cell and body (mailroom)
7. Cytoplasm: clear gelatinous fluid
inside a cell
8. Vacuoles: storage area of the cell
Plant has one large vacuole
Stores food, waste, & enzymes
9. Mitochondria = powerhouse of the cell; where
cell energy comes from.
10. Chloroplasts: ONLY IN PLANTS
captures sunlight and produces food
for the cell
11. Flagella = used for movement
12. Cilia = used for movement; tiny
hair-like structures; found on
cells that need to move mucus
D. Absence of a nuclear
membrane
B. Viruses require a host cell to
reproduce.
C. flagellum
B. flagella
Questions they (OGT) has asked
the last 4 years.
D. Place the rabbit in a cage with
a heated floor.
B.
D.
Evolution
Charles Darwin (1809-1882)
1. Natural Selection
a. “Only the strongest survive”
2. Darwin hypothesized that when
animals had traits that helped them
live, they would pass them on to their
offspring.
3. Animals who did not possess these
traits died.
Darwin’s Example
1. Darwin noted the different beak
structures of finches depended on the
island they came from.
2. Finches who lived on islands plentiful in
nuts and berries had different beaks
than finches who lived on islands
plentiful in insects.
Even though all these birds are finches
they developed different beaks depending
on the plentiful food source of specific
islands.
Examples of Natural Selection
1.
Galapagos Iguanas
a.
b.
c.
d.
e.
Some iguanas have evolved
to eat algae.
Some iguanas have
developed large claws to
help them cling to rock.
These iguanas evolved
from other iguanas
because they need those
two traits to survive.
The algae eating, long
clawed iguanas passed
these trait on to their
young.
Iguanas not having that
trait.
Everyday green iguana
Galapagos marine iguana
Other adaptations
1.
Camaflouge
a. Enables species to
blend in with their
surroundings.
Can you find the snake’s head?
2. Mimicry – enables a
species to look like
other species
What part of the plant is this?
It’s not part of the plant
at all, it’s an insect.
Darwin Hypothetical
1.
2.
3.
•
•
Let’s say there was a new “killer” virus that affected dogs.
This flu bug only affected dogs with long hair. So, if a dog
had long hair (more than ¾ inch long) it would get the virus and
die.
In 20 years, will all dogs have long or short hair? WHY?
All dogs would have short hair because all the long hair dogs
have died from the virus. There would only be short haired
dogs mating with short hair dogs.
You could say all dogs with short hair were “naturally
selected” to live. The dog species has evolved from having
both short and long hair to having only short hair.
1. Populations evolve not individuals.
B.
C. Had a higher survival rate than
light moths in the same area
One last thing the OGT might get
you on……
• Jean Baptiste Lamarck (1744-1821)
–
–
–
–
Came before Darwin
Had some of the same ideas as Darwin
No one ever believed him.
Died in obscurity and poverty.
Genetics
1. The dominant trait will always be visible
2. Dominant-always masks the recessive;
represented by uppercase letter (T, H, D, R)
3. Recessive-will be masked by dominant;
represented by lowercase letter (t, h, d, r)
-For a recessive trait to be visible, there
must be two (tt, hh, dd, rr)
Pedigrees
XY
c
XX
CC
Father
XX
C c
Daughter
Mother
XY
C
Son
XY
C
Son
Down Syndrome Karyotype
Darwin’s Background
• Born in England, 1809
• Studied Medicine at
Edinburgh University
• Transferred to Cambridge
University
• Studied to be a Minister
Library of Congress, Prints and
Photographs Division [reproduction
number, e.g., LC-USZ61-104].
Charles Darwin
• Wrote in 1859:
“On the Origin of Species
by Means of Natural Selection”
• Two main points:
1. Species were not created in their present
form, but evolved from ancestral species.
2. Proposed a mechanism for evolution:
NATURAL SELECTION
Chapter 15
Section 1 History of Evolutionary
Thought
http://player.discoveryeducation.com/index.cfm?guidAssetId=3941
21AC-2256-43A7-8F70367D66017CFC&blnFromSearch=1&productcode=US
Darwin’s Voyage
Example of Natural Selection
Analogous Structures
• Different structure
design, same
purpose.
Homologous Structures
• Different uses, same
design
What is Convergent Evolution?
• Different unrelated species demonstrate
similar traits in response to environment.
What is divergent Evolution?
• Common ancestor
• Develop different
traits
II. Mendel’s Legacy
A. Observed 7 traits (a genetically determined
variant of a characteristic) of Garder Peas
A.
B.
C.
D.
E.
F.
G.
Height
Flower position
Pod color
Pod appearance
Seed texture
Seed color
Flower color
XI. Homozygous dominant x
Homozygous recessive
• Purple is dominant over white
• PP (purple) x pp (white)
p
p
Genotypic ratio = 4:0
P
P p
P
P p
P p
P
p
Phenotypic ratio = 4
purple : 0 white
XII. Homozygous dominant x
heterozygous
• Purple is dominant over white
• PP (purple) x Pp (purple)
P
p
p
Genotypic ratio = 2:2
P
P P
P
P P
P p
P
p
Phenotypic ratio = 4
purple : 0 white
XIII. heterozygous x heterozygous
• Purple is dominant over white
• Pp (purple) x Pp (purple)
p
P
Genotypic ratio = 1:3:1
P
P P
p
P p
P p
p
p
Phenotypic ratio = 3
purple : 1 white
XIV. Incomplete dominance
• In roses (R = red, Rr
= pink, rr = white)
r
R
Genotypic ratio = 1:3:1
R
P
r
R R
R r
R r
r
r
Phenotypic ratio = 1 red:
2 pink: 2 white
XV. Co-Dominance
• In guinea pigs (B = black, Bb = black and white, bb = white)
c. taxonomy.
• The science of classifying living things is
called
• a. identification. c. taxonomy.
• b. classification. d. speciation.
c.
become more similar in
appearance.
• As we move through the biological hierarchy
from the kingdom to species level, organisms
• a. vary more and more.
• b. are less and less related to each other.
• c. become more similar in appearance.
• d. always are members of the same order.
c. Quercus.
• The organism Quercus phellos is a
member of the genus
• a. Plantae. c. Quercus.
• b. phellos. d. Protista.
d. toxicodendron.
• Poison ivy is also known as Rhus
toxicodendron. Its species identifier is
• a. poison. c. ivy.
• b. Rhus.
d. toxicodendron.
d. Acer rubrum.
• The red maple is also known as Acer
rubrum. Its scientific name is
• a. red maple.
c. rubrum.
• b. Acer.
d. Acer rubrum.
c.
kingdom, phylum, class, order,
family, genus, species.
• The correct order of the biological hierarchy from
kingdom to species is
• a. kingdom, class, family, order, phylum, genus,
species.
• b. kingdom, phylum, order, family, class, genus,
species.
• c. kingdom, phylum, class, order, family, genus,
species.
• d. kingdom, class, order, phylum, family, genus,
species.
b. species.
• The lowest hierarchy level in biological
classification is the
• a. genus. c. family.
• b. species. d. order.
d. species
• Which of the following is the least inclusive
classification group?
• a. class
c. phylum
• b. genus
d. species
Refer to the illustration above. A
branching diagram like the one
shown is called a
a. phenetic tree.
c. family tree.
b. cladogram.
b. cladogram.
d. the Galápagos Islands.
• Darwin drew ideas for his theory from
observations of organisms on
• a. the Samoan Islands.
• b. Manhattan Island.
• c. the Hawaiian Islands.
• d. the Galápagos Islands.
c.
•
•
•
•
•
because of natural selection.
According to Darwin, evolution occurs
a. only through artificial selection.
b. during half-life periods of 5,715 years.
c. because of natural selection.
d. so rapidly that it can be observed
easily.
c. the idea that species are
permanent and unchanging.
• When Darwin published his first book about
evolution, he included all of the following ideas
except
• a. the idea that species change slowly over
time.
• b. the idea that some organisms reproduce at a
greater rate than others.
• c. the idea that species are permanent and
unchanging.
• d. the idea that some species become better
suited to their environment than others.
d. species change over time by
natural selection.
• The major idea that Darwin presented in his
book The Origin of Species was that
• a. species change over time and never
compete with each other.
• b. animals change, but plants remain the same
over time.
• c. species may change in small ways but
cannot give rise to new species.
• d. species change over time by natural
selection.
b.
organisms with traits well suited to their environment survive and
reproduce more successfully than organisms less suited to the same
environment.
• Natural selection is the process by which
• a. the age of selected fossils is calculated.
• b. organisms with traits well suited to their
environment survive and reproduce more
successfully than organisms less suited to the
same environment.
• c. acquired traits are passed on from one
generation to the next.
• d. All of the above
c. adaptation.
• The process by which a population
becomes better suited to its environment
is known as
• a. accommodation.
c. adaptation.
• b. variation. d.
acclimation.
a. had a common ancestor.
• The species of finches that Darwin
observed differed in the shape of their
beaks. According to Darwin, all of these
species probably
• a. had a common ancestor.
• b. had migrated from Africa.
• c. had descended from similar birds in
Africa.
• d. ate the same diet.
d.
become increasingly different as each population becomes adapted to its own
environment.
• Populations of the same species living in
different places
• a. do not vary.
• b. always show balancing selection.
• c. are genetically identical to each other.
• d. become increasingly different as each
population becomes adapted to its own
environment.
b. must compete for resources.
• Since natural resources are limited, all
organisms
• a. must migrate to new habitats.
• b. must compete for resources.
• c. display vestigial structures.
• d. have inherited characteristics.
Refer to the illustration above. The bones
labeled “X” can be referred to as
a.
vestigial structures.
b.
sequential structures.
c.
homologous structures.
d.
fossil structures.
c.
homologous structures.
a. share a common ancestor.
• Homologous structures in organisms
provide evidence that the organisms
• b. must have lived at different times.
• c. have a skeletal structure.
• d. are now extinct.