IB Biology HL Exam with Accurate
Solutions
What are the characteristics common to all forms of life? - ANS-reproduction, carbon,
responds to surroundings, Growth and Development, cellular organization, and energy
What are the levels of biological organization from simple to most complex? - ANS-
Molecules, cell, tissue, organ, organism, population, community, ecosystem, biosphere
What are the 4 most common types of biological molecules? - ANS-Proteins, nucleic
acids, carbohydrates, and lipids
Organelle - ANS-any of a number of organized or specialized structures in a living cell
Cell - ANS-The smallest structure and functional unit of an organism.
Tissue - ANS-The material of specialized cells and their products that make a wall of
cells and their products
Organ - ANS-a part of an organism that is self-contained and serves a function
Organism - ANS-an individual animal, plant, or single-celled life form
What are the similarities and differences of a population and an ecosystem? - ANS-a
population and ecosystem both include organisms, however a population is one type of
species while an ecosystem is both biotic and abiotic things.
What is the definition of emergent properties? - ANS-the feature that can't be directly
from the features of its simpler parts eg. the taste of salt w/ the combination of Na+Cl
What are the 4 shared characteristics of cells? - ANS-DNA, cytoplasm, ribosome, and
plasma membranes
What is the definition of unicellular organisms? - ANS-an organism that consists only of
1 cell eg. bacteria/microorganisms
What is the definition of multicellular organisms? - ANS-an organism that consists of
multiple cells eg. human
What are the similarities and differences between prokaryotic and - ANS-eukaryotic
cells? Prokaryotic cells have no nuclei, unlike Eukaryotic cells. Both are enclosed by
,membranes and have DNA. Prokaryotic cells have no independent organelles, except
for the organelle of ribosome
How do the cells in multicellular organisms become specialized? - ANS-By controlling
what DNA is expressed in one cell, because all of the cells in an organism have the
same DNA, but only express some. This might include how tight the bindings of the
protein are, and if protein is made what the microRNAs do
What is sexual reproduction? - ANS-the production of a new living organism by
combining genetics of 2 different sexes/fusion of 2 gametes
What is asexual reproduction? - ANS-the reproduction of offspring without the fusion of
gametes.
How do Growth and Development differ? - ANS-Growth is the process of Development,
which is getting bigger/stronger/smarter
When consumers die, what gets nutrients and energy from the dead? - ANS-The
saprotrophs and detritivores
What is the definition of homeostasis and an example? - ANS-The ability or tendency of
an organism or cell to maintain internal equilibrium by adjusting its physical processes.
eg. body temperature in mammals
What is the definition of metabolism? - ANS-The chemical processes in living organisms
in order to maintain life. eg. the mammal's body metabolism can change the need and
absorption of energy, depending on environment
How does "response to environment" differ from "adaptation to environment?" - ANS-
Response involves the behavior that results from the environment, while adaptation is
how structures or functions of an organism change in order to better survive in the
environment.
What is the definition of adapt? - ANS-to adjust to the environment
What is the definition of anabolism? - ANS-constructive metabolism that synthesizes
more complex substances from simple substances
What is the definition of an atom? - ANS-The smallest unit of matter
What is the definition of autotroph? - ANS-any organism capable of self nourishment to
get energy
What is the definition of Biome? - ANS-a large naturally occuring community of fauna
and flora occupying that habitat
,What is the definition of biosphere? - ANS-it is the part of the earth's crust, waters, and
atmosphere that support life
What is the definition of catabolism? - ANS-the metabolism breaking down complex into
simple substances with the release of energy
What is the definition of cell? - ANS-the smallest functioning structure of living matter
What is the definition of cell membrane? - ANS-The semipermeable membrane
enclosing the cytoplasm of a cell
What is the definition of community? - ANS-a set of species found in the same place at
the same time
What is the definition of cytoplasm? - ANS-The cell substance between cell membrane
and nucleus
What is the definition of detritivore? - ANS-an organism that uses organic waste as a
food source
What is the definition of differentiation? - ANS-process by which cells or tissues
change/specialize in development
What is an electron? - ANS-an elementary particle having negative charge and exists
outside of the nucleus (electron cloud)
What is evolution? - ANS-process how different living organisms developed and
diversified
What is growth? - ANS-increasing in amount or complexity
What is a heterotroph? - ANS-organism deriving nutrients from complex organic
substances
What is a molecule? - ANS-a group of atoms bonded together
What is a neutron? - ANS-a neutrally charged ion inside the nucleus with proton
What is organization? - ANS-organic structure or compositions
What is a proton? - ANS-A positive ion in the nucleus with a neutron
What are ribosomes? - ANS-tiny mitten-shaped organelles that manufacture proteins
What is a saprotroph? - ANS-organism that live and feeds on dead organic matter
, What is tissue? - ANS-An aggregate of similar cells and cell products
What happens to the SA:V ratio when the size of the cell increases? - ANS-the ratio is
becoming smaller ad smaller, giving a cell less surface area for the transport of nutrients
for given unit volume
What does the amount of surface area for a cell dictate? - ANS-the larger the SA is, the
rate of diffusion halves each time cell doubles size, and the cell has a limit before it is
too large to metabolize
What does the amount of volume dictate in a cell? - ANS-the number of reactions
increase in a cell the larger the volume
What are some adaptations by cells to maximize their SA:V ratio? - ANS-Creating many
more cell folds (Crista) in their cell membranes to maximize the SA which speeds up the
processes of cellular metabolism
What is the function of a cell membrane? - ANS-To protect the nucleus and filter
particles
What is the structure of a phospholipid? - ANS-made up of 2 hydrophobic tails for each
hydrophilic head. Structure is flexible and changes shape easily due to fluidity. Structure
is strong due to attraction between hydrophobic tails
How are integral proteins different from peripheral proteins? - ANS-integral protein is
inside the lipid bilayer, where peripheral protein are attached to the hydrophilic heads of
the bilayer
What are the 4 functions of membrane bound proteins? - ANS-a) Immune system
receptors (b) act as carrier proteins to transport molecules across cell membranes (c)
signal transduction (d) cell-cell adhesion
Why are carrier proteins and channel proteins different types of transport proteins? -
ANS-both are integral membrane proteins involved in moving things across the
membrane and both have specific targets, but carrier proteins transport molecules by
changing shape while channel proteins are like tubes to transport. Carrier proteins are
saturated, while channel proteins are unsaturated
Why are phospholipids in the membrane fluid? - ANS-fluid membranes allow cells to be
dynamic and responsive in their environment
Why are some fatty acids considered saturated while others are unsaturated? - ANS-
saturated fatty acids are evenly filled with hydrogen, while double bonds in the
hydrocarbon chain create unsaturated fatty acids
Solutions
What are the characteristics common to all forms of life? - ANS-reproduction, carbon,
responds to surroundings, Growth and Development, cellular organization, and energy
What are the levels of biological organization from simple to most complex? - ANS-
Molecules, cell, tissue, organ, organism, population, community, ecosystem, biosphere
What are the 4 most common types of biological molecules? - ANS-Proteins, nucleic
acids, carbohydrates, and lipids
Organelle - ANS-any of a number of organized or specialized structures in a living cell
Cell - ANS-The smallest structure and functional unit of an organism.
Tissue - ANS-The material of specialized cells and their products that make a wall of
cells and their products
Organ - ANS-a part of an organism that is self-contained and serves a function
Organism - ANS-an individual animal, plant, or single-celled life form
What are the similarities and differences of a population and an ecosystem? - ANS-a
population and ecosystem both include organisms, however a population is one type of
species while an ecosystem is both biotic and abiotic things.
What is the definition of emergent properties? - ANS-the feature that can't be directly
from the features of its simpler parts eg. the taste of salt w/ the combination of Na+Cl
What are the 4 shared characteristics of cells? - ANS-DNA, cytoplasm, ribosome, and
plasma membranes
What is the definition of unicellular organisms? - ANS-an organism that consists only of
1 cell eg. bacteria/microorganisms
What is the definition of multicellular organisms? - ANS-an organism that consists of
multiple cells eg. human
What are the similarities and differences between prokaryotic and - ANS-eukaryotic
cells? Prokaryotic cells have no nuclei, unlike Eukaryotic cells. Both are enclosed by
,membranes and have DNA. Prokaryotic cells have no independent organelles, except
for the organelle of ribosome
How do the cells in multicellular organisms become specialized? - ANS-By controlling
what DNA is expressed in one cell, because all of the cells in an organism have the
same DNA, but only express some. This might include how tight the bindings of the
protein are, and if protein is made what the microRNAs do
What is sexual reproduction? - ANS-the production of a new living organism by
combining genetics of 2 different sexes/fusion of 2 gametes
What is asexual reproduction? - ANS-the reproduction of offspring without the fusion of
gametes.
How do Growth and Development differ? - ANS-Growth is the process of Development,
which is getting bigger/stronger/smarter
When consumers die, what gets nutrients and energy from the dead? - ANS-The
saprotrophs and detritivores
What is the definition of homeostasis and an example? - ANS-The ability or tendency of
an organism or cell to maintain internal equilibrium by adjusting its physical processes.
eg. body temperature in mammals
What is the definition of metabolism? - ANS-The chemical processes in living organisms
in order to maintain life. eg. the mammal's body metabolism can change the need and
absorption of energy, depending on environment
How does "response to environment" differ from "adaptation to environment?" - ANS-
Response involves the behavior that results from the environment, while adaptation is
how structures or functions of an organism change in order to better survive in the
environment.
What is the definition of adapt? - ANS-to adjust to the environment
What is the definition of anabolism? - ANS-constructive metabolism that synthesizes
more complex substances from simple substances
What is the definition of an atom? - ANS-The smallest unit of matter
What is the definition of autotroph? - ANS-any organism capable of self nourishment to
get energy
What is the definition of Biome? - ANS-a large naturally occuring community of fauna
and flora occupying that habitat
,What is the definition of biosphere? - ANS-it is the part of the earth's crust, waters, and
atmosphere that support life
What is the definition of catabolism? - ANS-the metabolism breaking down complex into
simple substances with the release of energy
What is the definition of cell? - ANS-the smallest functioning structure of living matter
What is the definition of cell membrane? - ANS-The semipermeable membrane
enclosing the cytoplasm of a cell
What is the definition of community? - ANS-a set of species found in the same place at
the same time
What is the definition of cytoplasm? - ANS-The cell substance between cell membrane
and nucleus
What is the definition of detritivore? - ANS-an organism that uses organic waste as a
food source
What is the definition of differentiation? - ANS-process by which cells or tissues
change/specialize in development
What is an electron? - ANS-an elementary particle having negative charge and exists
outside of the nucleus (electron cloud)
What is evolution? - ANS-process how different living organisms developed and
diversified
What is growth? - ANS-increasing in amount or complexity
What is a heterotroph? - ANS-organism deriving nutrients from complex organic
substances
What is a molecule? - ANS-a group of atoms bonded together
What is a neutron? - ANS-a neutrally charged ion inside the nucleus with proton
What is organization? - ANS-organic structure or compositions
What is a proton? - ANS-A positive ion in the nucleus with a neutron
What are ribosomes? - ANS-tiny mitten-shaped organelles that manufacture proteins
What is a saprotroph? - ANS-organism that live and feeds on dead organic matter
, What is tissue? - ANS-An aggregate of similar cells and cell products
What happens to the SA:V ratio when the size of the cell increases? - ANS-the ratio is
becoming smaller ad smaller, giving a cell less surface area for the transport of nutrients
for given unit volume
What does the amount of surface area for a cell dictate? - ANS-the larger the SA is, the
rate of diffusion halves each time cell doubles size, and the cell has a limit before it is
too large to metabolize
What does the amount of volume dictate in a cell? - ANS-the number of reactions
increase in a cell the larger the volume
What are some adaptations by cells to maximize their SA:V ratio? - ANS-Creating many
more cell folds (Crista) in their cell membranes to maximize the SA which speeds up the
processes of cellular metabolism
What is the function of a cell membrane? - ANS-To protect the nucleus and filter
particles
What is the structure of a phospholipid? - ANS-made up of 2 hydrophobic tails for each
hydrophilic head. Structure is flexible and changes shape easily due to fluidity. Structure
is strong due to attraction between hydrophobic tails
How are integral proteins different from peripheral proteins? - ANS-integral protein is
inside the lipid bilayer, where peripheral protein are attached to the hydrophilic heads of
the bilayer
What are the 4 functions of membrane bound proteins? - ANS-a) Immune system
receptors (b) act as carrier proteins to transport molecules across cell membranes (c)
signal transduction (d) cell-cell adhesion
Why are carrier proteins and channel proteins different types of transport proteins? -
ANS-both are integral membrane proteins involved in moving things across the
membrane and both have specific targets, but carrier proteins transport molecules by
changing shape while channel proteins are like tubes to transport. Carrier proteins are
saturated, while channel proteins are unsaturated
Why are phospholipids in the membrane fluid? - ANS-fluid membranes allow cells to be
dynamic and responsive in their environment
Why are some fatty acids considered saturated while others are unsaturated? - ANS-
saturated fatty acids are evenly filled with hydrogen, while double bonds in the
hydrocarbon chain create unsaturated fatty acids
