Download Question Answer Which process occurs in the mitochondria in cells

B3
Question
Answer
Which process occurs in the
mitochondria in cells?
Why do the liver and muscle cells have
large number of mitochondria?
What is the function of the
ribosomes?
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Respiration occurs in the mitochondria in cells.
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Liver and muscle cells require more energy so have more
mitochondria.
Ribosomes are the site of protein synthesis.
Where are the ribosomes situated?
What do you need to use to see
ribosomes and some other structures
in cells?
What substance are chromosomes made
of?
What do chromosomes carry?
What is the name of the coded
information in genes?
What does DNA control?
What are proteins needed for?
What is the structure of DNA?
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Ribosomes are in the cytoplasm
A microscope.
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Chromosomes are made of DNA
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Coded information in the form of genes.
The genetic code
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DNA controls the production of proteins
Proteins are needed for growth and repair.
DNA has two strands coiled to form a double helix
Each strand contains chemicals called bases – there are
four types
Cross-links are formed between the strands by pairs of
bases.
Genes.
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Chromosomes are divided into areas
called?
What does each gene contain?
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Each gene contains a different sequence of bases
Each gene codes for a particular protein.
Proteins are made in the cytoplasm (ribosomes)
A copy is needed because the gene itself cannot leave
the nucleus.
A, T, G and C
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A-T and G-C.
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The base sequence determines the amino acid
sequence in proteins.
What is the name of the molecule that
takes information from the DNA to the
ribosomes?
How does DNA control cell function?
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mRNA takes information from DNA to the ribosomes
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What are the names of the scientists that
first worked out the structure of DNA?
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DNA controls cell function by controlling the production of
proteins – some of which are enzymes.
Watson and Crick were the first to work out the structure
of DNA.
What information from other scientists
did Watson and Crick use to determine
the structure of DNA?
Why wasn’t Watson and Crick’s
discovery accepted immediately?
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X-ray data showing the double helix structure
Data indicating that the bases occurred in pairs
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Work of scientists needs to be repeated or tested by
other scientists before it is accepted.
Give three examples of proteins.
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Collagen
Where are proteins made?
Why is a copy of the gene needed to
make proteins?
What are the four letters that
represent the four bases in DNA?
What are the complimentary base
pairs??
What does the base sequence in DNA
determine in proteins?
What are proteins made of?
What are the functions of proteins?
Why do proteins have different
functions?
What do enzymes do to chemical
reactions?
What are enzymes made of?
When do enzymes work best?
Which biological processes do enzymes
catalyse?
What is meant by the ‘lock and key’
mechanism?
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Insulin
Haemoglobin.
Long chains of amino acids
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Structure (collagen)
Hormones (insulin)
Carrier molecules (haemoglobin)
Enzymes
Different proteins have different functions because they
have different sequences of amino acids.
Enzymes speed up chemical reactions
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Enzymes are proteins.
Enzymes work best at certain temperatures
Respiration
Photosynthesis
Protein synthesis.
Enzymes have a high specificity for their substrate
Enzymes have an active site that only fits certain
substrates
By changing the pH
By changing the temperature.
How can the rate of an enzyme catalysed
reaction be changed?
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What happens to enzymes at high
temperature or pH?
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What does denaturing do to the
enzyme’s active site?
What are gene mutations?
What will different cells produce?
What might gene mutations lead to?
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How can mutations occur?
Are mutations always harmful?
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Do all cells use the full set of genes
contained in each cell?
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How do genetic mutations lead to
different protein production?
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Where does the energy for all life
processes come from?
What is the word equation for
respiration?
Which processes require energy from
respiration?
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Respiration
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Glucose + oxygen  carbon dioxide + water
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Muscle contraction
Protein synthesis
Control of body temperature in mammals
C6H12O6 + O2  CO2 +H2O.
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ATP
What is the symbol equation for
photosynthesis?
Apart from carbon dioxide and water
what substance does respiration
result in the production of?
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Enzymes denature at extreme temperature or pH
Denaturing in an irreversible process and stops the
enzyme from working properly
Denaturing changes the shape of the active site.
Changes to genes
Different cells will produce different proteins.
Gene mutations may lead to the production of different
proteins.
Spontaneously
Due to radiation
Due to chemicals
Mutations are not always harmful; they can sometimes be
beneficial or have no effect.
No, some genes are switched off.
Which cells are switched off determines the function
of the cell
Gene mutations change the sequence of bases in the
gene which leads to changes in the amino acid
sequence in the protein produced.
What is ATP used for?
Why can oxygen consumption be
used as an estimate for metabolic
rate?
Why is the rate of respiration
influenced by changes in pH and
temperature?
Why do breathing and pulse rate
increase during exercise?
Why does anaerobic respiration take
place during hard exercise in addition to
aerobic respiration?
What is the name of the substance
produced by anaerobic respiration that
causes pain and fatigue?
What is the word equation for anaerobic
respiration?
Which process produces the most energy
per glucose molecule – aerobic or
anaerobic respiration?
What is fatigue in terms of lactic acid
build up (oxygen debt) and how is this
removed during recovery?
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ATP is the energy source for many processes in cells
Because aerobic respiration requires oxygen
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Enzymes are used in respiration and changes in pH
and temperature will cause the enzymes to denature.
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The muscle cells require more oxygen when exercising.
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Oxygen cannot be supplied to the muscles fast enough
for all energy required to be produced by aerobic
respiration.
Lactic acid
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Glucose  lactic acid
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Aerobic respiration
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Hard exercise causes lack of oxygen in cells
This results in the incomplete breakdown of glucose.
Continued panting after exercise to replace oxygen
allowing aerobic respiration
Heart rate increased to ensure that blood carries
lactic acid away to the liver.
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In terms of cells, what is the difference
between an amoeba and a dog?
What are the advantages of being
multicellular?
Why do multicellular organisms
require specialised organ systems?
How are chromosomes arranged in most
body cells?
Why do chromosomes have to be copied
to produce new cells?
Why is cell division necessary?
What is the name of the process that
creates new cells for growth?
What are cells that have two copies of
each chromosome called?
Why does DNA have to be replicated
before cells divide?
How does DNA replicate?
What happens to chromosomes
during mitosis?
What are sperm and egg cells called?
What happens to gametes during
fertilisation?
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An amoeba is a unicellular organism and a dog is a
multicellular organism.
Allows organisms to be larger
Allows for cell differentiation
Allows organism to become more complex.
Communication between cells
Supplying the cells with nutrients
Controlling exchanges with the environment.
They are arranged in pairs.
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So that the new cells have exactly the same genetic
information as the original.
To replace worn out cells
To repair damaged tissue
For asexual reproduction
Mitosis
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Diploid
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So when the cell divides the daughter cells have a
complete set of DNA.
The DNA ‘unzips’ to form single strands.
New double strands forming by complementary base
pairing.
The chromosomes line up along the centre of the cell.
They then divide
The copies move to opposite poles of the cell.
Gametes
The gametes join during fertilisation.
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How many chromosomes do gametes
have in comparison to body cells?
When creating a unique individual where
do half the genes come from?
Why are sperm cells are produced in
large numbers?
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Gametes have half the number of chromosomes
compared to body cells.
In sexual reproduction to produce a unique individual half
the genes come from each parent.
To increase the chance of fertilisation.
How are gametes produced?
What is the term for a cell with one copy
of each chromosome?
Why does fertilisation result in genetic
variation?
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Gametes are produced by meiosis.
Haploid
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Gametes combine to form a diploid zygote
Genes on the chromosomes combine to control the
characteristics of the zygote.
To provide energy
Why does a sperm cell have many
mitochondria?
What does the acrosome in a sperm cell
do?
Why is the chromosome number
halved in meiosis?
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The acrosome releases enzymes to digest the egg
membrane.
One chromosome from each pair separate to opposite
poles of cells in the first division
In the second division the chromosomes divide and
move to the opposite ends of the cell
This makes each cell genetically different.
What is the function of the red blood
cells?
What is the function of the white blood
cells?
What is the function of platelets?
How is a red blood cell adapted to its
function?
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Red blood cells carry oxygen around the body
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White blood cells protect the body from infection
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What is the function of plasma?
What is the name of the substance
formed when oxygen and
haemoglobin react?
Where does the reverse of the above
reaction take place?
What are the three blood vessels in the
body?
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Platelets help blood to clot
Small enough to fit through the membranes of capillaries
Shaped so that it has a large surface area
Contains haemoglobin to carry oxygen and carbon dioxide
No nucleus to maximise space to carry oxygen and
carbon dioxide
Carries other chemicals around the body
Oxyhaemoglobin
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In the tissues
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Arteries
Veins
Capillaries
Arteries transport blood away from the heart
Veins transport blood to the heart
Capillaries exchanging materials with tissues
Arteries have thick muscular and elastic walls
Veins have large lumen and values to prevent back
flow
Capillaries have permeable walls
The right side of the heart pumps blood to the lungs
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What do the three blood vessels in the
body do?
How are the three blood vessels
adapted to their functions?
Where does the right side of the heart
pump blood to?
Where does the left side of the heart
pump blood to?
Where is blood at higher pressure –
veins or arteries?
Why does blood flow from one place to
another?
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The left side of the heart pumps blood to the rest of the
body
Blood is at higher pressure in the arteries
Blood flows from areas of high pressure to areas of low
pressure
What do the left and right ventricles in
the heart do?
Why does the left ventricle have a
thicker muscle wall than the right
ventricle?
What do the left and right atria in the
heart do?
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They pump blood.
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The left ventricle has to pump blood around the entire
body.
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The receive blood.
What do the semilunar, tricuspid and
bicuspid valves do in the heart?
What are the four main blood vessels of
the heart?
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They prevent backflow.
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Aorta
Vena cava
Pulmonary vein
Pulmonary artery
Can pump at higher pressure
Therefore greater rate of flow to the tissues
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Contains cell sap and provides support
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Cellulose to provide support
Bacterial cells are simpler and smaller than animal and
plant cells.
A ‘true’ nucleus
Mitochondria
Chloroplasts
No nucleus in a bacterial cell
Circular strand in a bacterial cell and chromosomes in
an animal/plant cell
As an increase in height
As an increase in wet or dry mass
Dry mass
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One just after birth
One in adolescence
Cell division then cells becoming specialised
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Cell differentiation
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Stem cells
Embryonic tissue
Different cells, tissues and organs
Adult stem cells can only become certain cells.
Embryonic stem cells can become all types of body
cell
Animals only grow in the early stages of their lives and
reach a finite size
Plants grow continually
All parts of an animal are involved in growth
Plants grow at specific parts of the plant.
Meristems
What is the advantage of the double
circulatory system in mammals?
What is the function of the vacuole in a
plant cell?
What is the cell wall made of?
What is the difference between bacterial
and animal and plants cells?
What do bacterial cells lack?
How is the arrangement of the DNA in
a bacterial cell and an animal/plant
cell different?
How can growth be measured?
What is the best measurement of
growth?
When are the two rapid phases of
growth in human growth?
How can growth be described in terms of
cell division?
What is the process by which cells
become specialised called?
What are undifferentiated cells called?
Where are stem cells obtained from?
What can stem cells develop into?
What is the difference between adult
and embryonic stem cells?
How is animal and plant growth
different?
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What is the name of the areas of plants
where cell division happens?
What is the main method by which plants 
gain height?
What do many plant cells keep but most 
animals lose at an early stage?
What is the process of selective
breeding?
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Cell enlargement
The ability to differentiate
Selection of desired characteristics
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How can selective breeding reduce
the gene pool?
What is artificially transferring genes
from living to another called?
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Cross breeding individuals with those characteristics
Selection of suitable offspring over may generations
Inbreeding which can cause health problems within the
species
Accumulation of harmful recessive characteristics
Reduction in variation
Genetic engineering or genetic modification
Give an advantage of genetic
engineering
Give a risk involved with genetic
engineering
Give three examples of genetic
engineering
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Organisms with desired features are produced rapidly
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Inserted genes may have unexpected harmful effects
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Inserting the gene from carrots that produces betacarotene into rice so that humans can process betacarotene into vitamin A from rice.
Production of human insulin by genetically engineered
bacteria
Transferring resistance to herbicides, frost damage or
disease to crop plants
Selection of desired characteristics
Isolation of genes responsible
Insertion of genes into other organisms
Replication of these organisms
Change a person’s genes and cure certain disorders
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Gene therapy
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Body cells or gametes
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If genes can be changed to cure disorders before
conception, what other genetic characteristics could
be changed prior to conception of a baby?
What can selective breeding lead to?
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What is the process of genetic
engineering?
What might it be possible for genetic
engineering to do in the future?
What is it called when a person’s genes
are changed in an attempt to cure
disorders?
What type of cells could gene therapy
involve?
Why is gene therapy involving
gametes controversial?