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Biology Review
Fall Semester
SCIENTIFIC METHOD AND LAB SAFETY
Ultimately, all scientific knowledge comes from:
• both experimentation and observation
Hypothesis
• A hypothesis must be:
• experimental
Independent Variable
• A scientist testing the affects of a chemical on an
apple sprays an orchard with the chemical. A
second orchard does not receive the chemical. In
the fall, the number of apples harvested from
each forest is counted. Which of the following is
the independent (manipulated) variable in the
experiment?
• the chemical
• the number of apples
• the first orchard
• the second orchard
Inventions
Which invention played the biggest role in the
discovery of cells by early scientists?
• compound microscope
SCIENTIFIC METHOD AND LAB SAFETY
• Ultimately, all scientific knowledge comes
from:
• both experimentation and observation
Evidence
If a theory is challenged by new evidence, which
of the following could occur?
• the theory could be altered.
Theories
Theories help scientists to:
• propose new ideas about how the world
works
Smallest Unit
The smallest unit capable of carrying out life
functions is:
• a cell
Lab Safety
What are good lab safety practices?
• always wear goggles
• no horseplay
• never eat or drink during a lab.
• What are the steps of the scientific method?
All living things must:
• maintain homeostasis
CELLS and CELL STRUCTURE
What are the main differences between plant
and animal cells?
• plant cells have cell walls and chloroplasts,
animals cells do not
Organelles
• Which organelles supply energy to the cell?
(also known as the powerhouse of the cell)
• Mitochondria
Organelles
• Which organelles contain enzymes that break
down old cell parts and defend a cell against
viruses? (also known as suicide cells)
• Lysosomes
Cell Movement
• Which sentence best describes endocytosis?
• contents enter a cell
Cell Movement
• Which sentence best describes exocytosis?
• contents exit a cell
Organelles
• Which organelles are unique to plant cells?
• Chloroplasts
Cell Theory
The cell theory states that all organisms are
made of cells; cells are the most basic unit of
life, and
• all existing cells are produced by other living
cells
Cell Parts
What is the term for the jellylike substance that
is contained inside the cell membrane?
• cytoplasm
Cell Parts
Unlike a eukaryotic cell, a prokaryotic cell does
not have
• a nucleus
Cell Parts
Specialized structures that work together inside
a cell are called
• Organelles
ATOMS, IONS AND MOLECULES
The smallest basic unit of matter is the
• Atom
Carbon Based Molecules
The four carbon based molecules are:
• Lipids, proteins, amino acids, carbohydrates
Bonds
Atoms in molecules share pairs of electrons
when the make
Covalent bonds
Acids and Bases
Which of the following solutions has the highest
H ion concentration? (also most basic)
•
•
•
•
solution with pH of 1
solution with pH of 4
solution with pH of 7
solution with pH of 10
Bonds
Substances are changed into different
substances when bonds break and form
during
chemical reactions
Energy
Chemical reactions that absorb more energy
than they release (also speed up reactions at a
lower temperature) are called…
catalyzed
DIFFUSION & OSMOSIS
Which of the following is NOT a type of passive
transport?
• diffusion
• osmosis
• endocytosis
• facilitated diffusion
DIFFUSION & OSMOSIS
• Which of the following phrases best describes
active transport?
• moves substance against concentration
gradient
• does not use chemical energy
• forms a vesicle around a large particle
• relies on diffusion of materials.
DIFFUSION & OSMOSIS
Transport proteins play a role in both
• passive and active transport
DIFFUSION & OSMOSIS
Diffusion is
• net transport of molecules from a region of
higher concentration to one of lower
concentration by random molecular motion.
• net transport of molecules from a region of
lower concentration to one of higher
concentration by random molecular motion.
• net transport of molecules from a region of
higher concentration to one of lower
concentration by specific molecular motion
DIFFUSION & OSMOSIS
• Osmosis is
• diffusion of a solvent through a semipermeable membrane
• diffusion of a solvent through a permeable
membrane
• diffusion of a solute through a permeable
membrane
• diffusion of a solute through a semipermeable membrane
DIFFUSION & OSMOSIS
A solute is
• a solid material (like sugar or salt) dissolved in
another substance
• a liquid material (like kool-aid) that is
dissolved in another substance.
• a solitary material
DIFFUSION & OSMOSIS
A solvent is
• a cleanser
• a liquid or gas that dissolves a solid, liquid or
gaseous solute resulting in a solution.
• a liquid or gas that dissolves only solids
resulting in a solution
Somatic Cells
• Also called Body Cells
• Make up most of your
body tissues and
organs
Germ Cells
• Are cells in your reproductive organs—ovaries
and testes that develop into gametes.
• Gametes are sex cells
-ova or eggs in female
-sperm in male
Mitosis
• During which stage of the cell cycle is the DNA
copied?
• Gap 1
Mitosis
• Mitosis can only happen in what type of cell?
– Eukaryotic cells
Mitosis
• The process where the cytoplasm divides and
forms two new cells is called:
• cytokinesis
MEOSIS
Meiosis results in _____
• 2 haploid daughter cells
• 4 haploid daughter cells
• 2 diploid daughter cells
• 4 diploid daughter cells
Meiosis
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Cell division to form the gametes, sperm (male
gamete) and egg (female gamete).
Characteristic of eukaryotes only: not in
prokaryotes.
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•
Normal cells are diploid: 2 copies of every gene.
Diploidy is useful because 2 copies of every gene
means that there a backup copy if one gets
mutated. Mutations are very frequent in the
cells of large organisms. We wouldn’t survive
with just one copy of each gene.
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•
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Gametes are haploid: 1 copy of every gene
Need to choose 1 copy of each gene randomly.
Why have sexual reproduction? Shuffling of
alleles between parents and offspring leads to
new combinations. Bad combinations die
without reproducing; good combinations survive
and reproduce more offspring.
Result of Meiosis 1
• Go from 1 cell to 2 cells. Each
daughter cell contains 1 copy of
each chromosome: they are
haploid, with the chromosomes
still having 2 chromatids each.
• For humans: start with one cell
containing 46 chromosomes (23
pairs) to 2 cells containing 23
chromosomes.
• As a result of crossing over, each
chromosome is the mixture of the
original homologues.
Meiosis 2
• Meiosis 2 is just like mitosis
• No replication of DNA between
meiosis 1 and meiosis 2.
• Chromosomes line up individually
on the equator of the spindle at
metaphase.
• At anaphase the centromeres
divide, splitting the 2 chromatids.
• The one-chromatid chromosomes
are pulled to opposite poles.
More Meiosis 2
Meiosis is a type of cell division that
produces:
• zygotes
• chromosomes
• DNA
• gametes
PHOTOSYNTHESIS, CELLULAR RESPIRATION
& FERMENTATION
• Which process is
best represented by
the following
chemical equation?
• Sugars + oxygen =
carbon dioxide +
water
Cellular Respiration
Before cellular respiration, glucose must be
broken down by the process of
Photosynthesis
Cellular Respiration
The universal currency for energy in a cell is
ATP
ATP/ADP
The unit which has a phosphorus group taken
away is called
• ADP
Cellular Respiration
• Which of the following groups of organisms
uses cellular respiration in mitochondria to
produce ATP for their energy needs?
• Plants only
• Eukaryotes
• Animals only
• Prokaryotes
• Lipids, proteins, nuclear reactants, oxygen
Fermentation
Fermentation does not produce ATP. Why is
fermentation such an important process to
cells?
• It allows glycolysis to continue to produce a
small amount of ATP when oxygen is
unavailable.
Cellular Respiration
Which of the following is a waste product
(reactant) in photosynthesis?
• Oxygen
• Glucose
• Carbon dioxide
• Carbon hydrotrioxide
CELLULAR REPRODUCTION
• Asexual reproduce is creation of offspring
from
• One parent
Cellular Reproduction
In asexual reproduce the offspring is
• Genetically identical to each other and the
single parent
Cellular Reproduction
Most prokaryotes reproduce through
• Binary fission
Cellular Reproduction
• Eurkayotes can reproduce asexually by all but
one of the following:
• a. stem cutting
• b. fragmentation
• c. replication
• d. cell differentiation
• Apoptosis is
• Programmed cell death
Cellular Reproduction
• How do most prokaryotes reproduce
reproduction
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How is mitosis different from binary fission?
a. mitosis is division of the cell nucleus
b. mitosis is involved in sexual reproduction
c. four daughter cells form in mitosis
d. the daughter cells formed by mitosis are
genetically differen
reproduction
How might asexually reproduction be
beneficially to a small animal in a widely
scattered area?
• a. it is more energy efficient than sexual
reproduction
• b. both male and female offspring are
produced by asexual reproduction
• c. the organism won’t have to spend time
looking for a mate
• d. the organism won’t need a nucleus
reproduction
• What term describes a form of reproduction
that involves gametes
• a. budding
• b. fragmentation
• c. vegetative reproduction
• d. sexual reproduction
STEM CELLS AND CELL
ORGANIZATION
Which of the following is correctly arranged
from smallest to largest?
• a. tissue, cell, organ, organ system
• b. organ, cell, organ system, tissue
• c. organ system, organ, tissue, cell
• d. cell, tissue, organ, organ system
Stem Cells
• What term describes the kind of stem cell that
can grow into all cell types in the body?
• a. totipotent
• b. pleuripotent
• c. multipotent
• d. adult stem cell
Homeostatis
How does communication between cells help
maintain homeostatsis?
• a. coordination of activities are needed to
maintain the body’s internal environment
• b. to know where to connect
• c. to make other differentiated cells
• d. coordinated cell division