paper 1 Flashcards
What are the three types of cell transport?
Diffusion, osmosis, and active transport.
What is the function of the mitochondria?
Site of aerobic respiration, where energy (ATP) is released.
What is the function of ribosomes?
Site of protein synthesis.
What is mitosis used for?
Growth, repair, and asexual reproduction.
Why are stem cells important?
They can develop into different cell types and be used in medicine.
What are the differences between prokaryotic and eukaryotic cells?
Prokaryotic cells (e.g., bacteria) have no nucleus and no membrane-bound organelles; eukaryotic cells (e.g., animal and plant cells) have a nucleus and organelles.
What is the function of the cell membrane?
Controls what enters and exits the cell.
What is the difference between plant and animal cells?
Plant cells have a cell wall, chloroplasts, and a permanent vacuole; animal cells do not.
What are the four components of blood?
Red blood cells, white blood cells, platelets, and plasma.
What do red blood cells do?
Carry oxygen using haemoglobin.
What is the function of white blood cells?
Defend the body against pathogens by engulfing, producing antibodies, and releasing antitoxins.
What is the function of platelets?
Help blood clot to stop bleeding.
What are the three types of blood vessels?
Arteries (carry blood away from the heart), veins (carry blood to the heart), capillaries (allow exchange of substances).
What is coronary heart disease (CHD)?
When fatty deposits build up in the coronary arteries, reducing blood flow and oxygen supply to the heart.
What lifestyle factors increase the risk of CHD?
Smoking, high-fat diet, lack of exercise, high blood pressure
What is the function of the digestive enzymes?
Amylase (starch → sugar), protease (protein → amino acids), lipase (lipids → fatty acids + glycerol).
What are the four main types of pathogens?
Bacteria, viruses, fungi, and protists.
How do viruses cause disease?
Invades cells, replicates, and bursts the cells, spreading infection
What is herd immunity?
When a large proportion of the population is vaccinated, reducing the spread of disease.
Why don’t antibiotics work on viruses?
: Viruses reproduce inside host cells, so antibiotics can’t target them without harming the host.
How are new drugs developed?
Tested in labs, then on animals, then human clinical trials including placebo tests.
Why does oxygen debt occur?
After anaerobic respiration, extra oxygen is needed to break down lactic acid.
What is the function of the nucleus?
Controls the activities of the cell and contains DNA
How is a root hair cell adapted for absorption?
Large surface area, thin cell wall, many mitochondria for active transport.
