Cells
What is the function of the mitochondria
performs aerobic respiration to release energy
what blood vessel carries blood away from the heart?
Arteries
What is the definition of a pathogen and four examples of?
A micro organism that causes disease e.g Protist, fungus, bacteria, virus
Who is credited with coming up with the theory of evolution through natural selection?
Charles Darwin
What are the three sub-atomic particles and their charge and relative mass?
Electron- negative- 0
Neutron- neutral- 1
Proton - positive - 1
What are 3 organelles found in plant cells but not animal cells
Chloroplasts, Permanent Vacuole, Cell wall
Name the four chambers of the heart in order of blood being pumped through
Right Atrium --> Right Ventricle --> Left Atrium --> left ventricle
What treats bacteria infections and name an example of one?
Antibiotic, Peniccillin
What is the only type of mammal that can fly
Bats
What is the unit for force and for energy?
Force - Newtons (N)
Energy - Joules (J)
Explain how is a root hair cell adapted to its function (3 points)?
Large surface area for absorption of water and minerals. Lots of mitochondria to release energy for active transport. No chloroplasts as root hair cells are underground so no access to sunlight for photosynthesis.
Xylem- transports water and mineral ions from roots to rest of plant- dead hollow tubes
phloem- Transports food molecules (Sugar)- sieve end plates
What are the three different types plant defence and give an example of each?
- Physical- cellulose in cell wall/ bark etc
- Chemical- poisons to deter herbivory e.g chilli
- Mechanical- thorns/ mimicry etc
what is the added total of the number of brains, hearts and limbs of an octopus?
brains= 9
Hearts = 3
limbs = 8
total = 20
What will happen to the motion of a car if the resultant force acting on the car is 0N?
The car will either remain stationary if it is not moving or travelling at a constant speed if it is moving
Where are stem cells in animals (2 places) and plants (1 place) and how are they different to other cells?
Animals= Embryos and Bone marrow
Plants = Meristem
They can differentiate into different cells
Less bile production and so fat not emulsified, so longer for lipase to digest fat and smaller surface area. Additionally bile neutralises stomach acid, less bile means HCL not neutralised and lipase in small intestines will be denatured.
Why would medicine with monoclonal antibodies be given to someone who has had a liver transplant?
The monoclonal antibodies bind to specific antigens on the transplanted liver as they are complementary. This prevents the antibodies from lymphocytes binding with the liver antigens. preventing the liver from being rejected.
what is the difference between precision, accuracy, and reliability?
Accuracy is how close a measured value is to the true value.
Precision is the consistency and repeatability of measurements.
Reliability is a combination of the two where consistency is kept across repetition.
Compare the properties of sodium chloride (NaCl) and oxygen (O2) in terms of bonding?
Sodium chloride forms an ionic bond between a metal and non-metal ion. Oxygen forms a covalent bond. In an ionic bond electrons are donated and received resulting in ions and in covalent bonding electrons are shared. NaCl forms a giant ionic lattice with strong electrostatic attraction between oppositely charged ions which require lots of energy to overcome. Oxygen forms simple molecules with weak intermolecular forces requires less energy to overcome.
What are three factors that influence rate of diffusion, how and why?
- concentration gradient - Greater concentration gradient greater rate of diffusion as particles move to an area of low concentration
- Temperature - greater temperature greater rate of diffusion due to greater kinetic energy and movement of particles.
- Surface area- greater surface area to volume ratio results in greater rate of diffusion as more surface for diffusion to occur
What are the tissues in a leaf and how are they adapted to help the leaf perform its function?
Waxy cuticle- prevents water loss and is transparent to allow sunlight to pass through
Palisade Mesophyll- Cells have many chloroplasts for photosynthesis
Spongey mesophyll- has many spaces for gas exchange to occur
Explain how vaccines are made and how they work?
A dead or weak version of the pathogen is injected. This stimulates the bodies lymphocytes to produce antibodies specific to the pathogen. If the person is reinfected the lymphocytes respond quickly and produce the specific antibodies preventing infection.
What does WHO stand for and why is it important
World health organisation
They monitor and prevent disease as well as co-ordinate global efforts to respond to health emergencies
Compare the I-V graph for an ohmic resistor, filament lamp and diode
Ohmic resistor- straight line through the origin and directly proportion.
Filament lamp- Current and potential difference not directly proportional as temp increases in filament lamp so does resistance so graph is s shaped
Diode-
The I–V graph for a diode is slightly different. When the current is in the direction of the arrowhead symbol, this is forward bias. This is shown by the sharp increase in potential difference and current on the right side of the graph