1. AQA GCSE Biology: Cell Biology
Active transport - ANS-Move substances from a more dilute solution to a more concentrated
solution (against a concentration gradient). This requires energy from respiration.
\Area of a circle - ANS-πr^2
\Calculating bacterial populations equation - ANS-Bacteria at the end of the growth period =
bacteria at the beginning of the growth period x 2^number of divisions
\Cell division by mitosis is important in... - ANS-...the growth and development of
multicellular organisms
\Cell membrane - ANS-Controls the passage of substances in and out of the cell e.g.
glucose and ions
\Chloroplasts - ANS-Where photosynthesis occurs because contain chlorophyll (in plant
cells)
\Chromosome - ANS-A structure made up of DNA molecules. Each chromosome carries a
large number of genes. In body cells these are normally found in pairs.
\Crenation - ANS-When an animal cell is put into a hypertonic solution - water has travelled
out by osmosis
\Culture medium - ANS-A liquid or gel containing nutrients for bacteria
\Cytokinesis - ANS-When the cell cytoplasm divides to form the daughter cells
\Cytoplasm - ANS-Where most chemical reactions take place
\Describe an investigation into the effects of osmosis on plant tissue. - ANS-1. Cut potato
chips using a cork borer, use scalpel to trim to same size
2. Find the mass and length of each chip
3. Pour 5cm3 water into test tube
4. Add 5cm3 of salt solutions of different concentrations
5. Leave for 30 mins
6. Remove chips and blot
7. Record masses and length of chip
\Describe the aseptic technique required to prepare an uncontaminated culture (4) - ANS-1.
Sterilise petri dishes and culture media (usually by heating)
2. Sterilise inoculating loop by passing through flame
3. Lid of petri dish secured with tape and stored upside down
4. Incubated at 25 degrees C (in school laboratories)
\Difference in antiseptic effectiveness = - ANS-diameter of largest zone of inhibition/diameter
of smallest zone of inhibition
\Diffusion - ANS-The spreading out of the particles of any substance in solution, or particles
of a gas. resulting in a net movement from an area of higher concentration to an area of
lower concentration
\During the cell cycle, the genetic material... - ANS-...is doubled and then divided into two
identical cells
\Electron microscopes - ANS-1. Invented in 1930s
2. Use beams of electrons to form an image
2. Can magnify up to 2,000,000 times - subcellular structures
3. Transmission microscopes give 2D images with high magnification and low resolution
4. Scanning electron microscopes give 3D images but with a lower resolution
, \Equipment for microscopy practical (6) - ANS-1. Microscope
2. Onion
3. Scalpel
4. Forceps
5. Slide and cover slip
6. Iodine
\Eukaryotic cells - ANS-Plant and animal cells
\Flaccid - ANS-When a plant cell is put into a hypertonic solution - the cell membrane
becomes plasmolysed
\Further cell division, stem cells, monoclonal antibodies and therapeutic cloning - ANS-See
this quizlet set:
https://quizlet.com/240906580/gcse-aqa-biology-cell-division-monoclonal-antibodies-flash-ca
rds/
\How are gills in fish adapted for exchanging materials? (3) - ANS-1. Many gill filaments
increase surface area
2. Gills have a rich blood supply - lots of capillaries
3. Pump water needed to maintain concentration gradient over gills with a flap called the
operculum
\How are leaves in plants adapted for exchanging materials? - ANS-Flat, thin leaves,
presence of air spaces and stomata help provide a big surface area and maintain a steep
concentration gradient
\How are molecules moved by active transport into cells? - ANS-By carrier proteins which
use energy from respiration to transport molecules against a concentration gradient
\How are muscle cells adapted for their function? (4) - ANS-1. Function: to generate
movement
2. Contain many mitochondria to transfer the energy needed
3. Can store glycogen which can be used in respiration to transfer the energy needed
4. Contain special proteins that slide over each other making the fibres contract
\How are nerve cells adapted for their function? (4) - ANS-1. Function: to transmit messages
from one part of the body to another
2. Axon is very long so easier to communicate over further distances
3. Dendrites (branched endings) allow connections with many other neurones
4. Nerve endings contain lots of mitochondria to provide energy to make transmitter
chemicals
\How are phloem cells adapted for their function? (3) - ANS-1. Function: to transport sugar
from the leaves to the rest of the plant (translocation)
2. Cell walls between cells form sieve plates (tiny holes) which allow dissolved food to move
between cells
3. Supported by companion cells which have mitochondria to transfer energy for
translocation
\How are root hair cells adapted for their function? (4) - ANS-1. Function: to absorb minerals
and nutrients from the soil
2. Increased surface are for water to move into the cell
3. Large permanent vacuole speeds up the movement of water by osmosis
4. Many mitochondria to transfer the energy needed for active transport
\How are roots in plants adapted for exchanging materials? (2) - ANS-1. Large surface area,
increased by root hair cells
Active transport - ANS-Move substances from a more dilute solution to a more concentrated
solution (against a concentration gradient). This requires energy from respiration.
\Area of a circle - ANS-πr^2
\Calculating bacterial populations equation - ANS-Bacteria at the end of the growth period =
bacteria at the beginning of the growth period x 2^number of divisions
\Cell division by mitosis is important in... - ANS-...the growth and development of
multicellular organisms
\Cell membrane - ANS-Controls the passage of substances in and out of the cell e.g.
glucose and ions
\Chloroplasts - ANS-Where photosynthesis occurs because contain chlorophyll (in plant
cells)
\Chromosome - ANS-A structure made up of DNA molecules. Each chromosome carries a
large number of genes. In body cells these are normally found in pairs.
\Crenation - ANS-When an animal cell is put into a hypertonic solution - water has travelled
out by osmosis
\Culture medium - ANS-A liquid or gel containing nutrients for bacteria
\Cytokinesis - ANS-When the cell cytoplasm divides to form the daughter cells
\Cytoplasm - ANS-Where most chemical reactions take place
\Describe an investigation into the effects of osmosis on plant tissue. - ANS-1. Cut potato
chips using a cork borer, use scalpel to trim to same size
2. Find the mass and length of each chip
3. Pour 5cm3 water into test tube
4. Add 5cm3 of salt solutions of different concentrations
5. Leave for 30 mins
6. Remove chips and blot
7. Record masses and length of chip
\Describe the aseptic technique required to prepare an uncontaminated culture (4) - ANS-1.
Sterilise petri dishes and culture media (usually by heating)
2. Sterilise inoculating loop by passing through flame
3. Lid of petri dish secured with tape and stored upside down
4. Incubated at 25 degrees C (in school laboratories)
\Difference in antiseptic effectiveness = - ANS-diameter of largest zone of inhibition/diameter
of smallest zone of inhibition
\Diffusion - ANS-The spreading out of the particles of any substance in solution, or particles
of a gas. resulting in a net movement from an area of higher concentration to an area of
lower concentration
\During the cell cycle, the genetic material... - ANS-...is doubled and then divided into two
identical cells
\Electron microscopes - ANS-1. Invented in 1930s
2. Use beams of electrons to form an image
2. Can magnify up to 2,000,000 times - subcellular structures
3. Transmission microscopes give 2D images with high magnification and low resolution
4. Scanning electron microscopes give 3D images but with a lower resolution
, \Equipment for microscopy practical (6) - ANS-1. Microscope
2. Onion
3. Scalpel
4. Forceps
5. Slide and cover slip
6. Iodine
\Eukaryotic cells - ANS-Plant and animal cells
\Flaccid - ANS-When a plant cell is put into a hypertonic solution - the cell membrane
becomes plasmolysed
\Further cell division, stem cells, monoclonal antibodies and therapeutic cloning - ANS-See
this quizlet set:
https://quizlet.com/240906580/gcse-aqa-biology-cell-division-monoclonal-antibodies-flash-ca
rds/
\How are gills in fish adapted for exchanging materials? (3) - ANS-1. Many gill filaments
increase surface area
2. Gills have a rich blood supply - lots of capillaries
3. Pump water needed to maintain concentration gradient over gills with a flap called the
operculum
\How are leaves in plants adapted for exchanging materials? - ANS-Flat, thin leaves,
presence of air spaces and stomata help provide a big surface area and maintain a steep
concentration gradient
\How are molecules moved by active transport into cells? - ANS-By carrier proteins which
use energy from respiration to transport molecules against a concentration gradient
\How are muscle cells adapted for their function? (4) - ANS-1. Function: to generate
movement
2. Contain many mitochondria to transfer the energy needed
3. Can store glycogen which can be used in respiration to transfer the energy needed
4. Contain special proteins that slide over each other making the fibres contract
\How are nerve cells adapted for their function? (4) - ANS-1. Function: to transmit messages
from one part of the body to another
2. Axon is very long so easier to communicate over further distances
3. Dendrites (branched endings) allow connections with many other neurones
4. Nerve endings contain lots of mitochondria to provide energy to make transmitter
chemicals
\How are phloem cells adapted for their function? (3) - ANS-1. Function: to transport sugar
from the leaves to the rest of the plant (translocation)
2. Cell walls between cells form sieve plates (tiny holes) which allow dissolved food to move
between cells
3. Supported by companion cells which have mitochondria to transfer energy for
translocation
\How are root hair cells adapted for their function? (4) - ANS-1. Function: to absorb minerals
and nutrients from the soil
2. Increased surface are for water to move into the cell
3. Large permanent vacuole speeds up the movement of water by osmosis
4. Many mitochondria to transfer the energy needed for active transport
\How are roots in plants adapted for exchanging materials? (2) - ANS-1. Large surface area,
increased by root hair cells
