Paper 1 Flashcards
What is a eukaryotic cell? What’s a prokaryote cell?
A eukaryotic cell is an animal or plant cell. Prokaryotes are bacteria.
What is the cell cycle?
Stage 1) Cells grow bigger, increase mass, and replicate their DNA
Stage 2) Mitosis- One set of chromosomes is pulled to each end of the dividing cell and the nucleus divides
Stage 3) Cytoplasm and cell membrane divide to form two identical daughter cells
What’s the tests for starch, carbohydrates, lipids and protein?
Carbohydrates- Benedict solution (blue to orange)
Starch- Iodine (turns blue black)
Lipids- Ethanol (cloudy white layers)
Proteins- Biuret (turns purple)
What is the structure of the lungs?
Diaphram-contracts to increase volume Alveoli- incases surface area Lung- organ Intercostal muscles- contracts to pull ribcage Trachea- carries air to and from lungs Bronchus-carries air in or out of lungs Bronchioles- carries air to alveoli
How does a stent reduce the risk of coronary heart disease?
It keeps open the narrow or blocked artery, to keep blood flowing and limit the buildup of fatty tissue
How does statins reduce the risk of coronary heart disease?
It reduces cholesterol levels, which limits any buildup in arteries
What does the phloem and xylem transport?
Xylem transports water and mineral ions. Phloem transports glucose/food.
What factors affect the transpiration rate?
Light intensity, temperature, air flow, and humidity
How are communicable pathogens spread?
Direct contact, air by droplets, and water
How can the spread of disease be reduced?
Improving hygiene, destroying or controlling vectors, vaccination, and isolating the infected.
Rose Black Spot a fungal, viral, or bacterial disease?
Fungal
How does the human body defend itself against disease/pathogens?
Skin- acts as a barrier, produces antimicrobial secretions to kill the pathogens
Nose, trachea, and bronchi- produces mucus that traps the pathogens from the air
Stomach- the acid kills any pathogens in food or drink, or in mucus
White blood cells- Phagocytes (engulf the pathogen) and lymphocytes (which produce antibodies)
What do plants need nitrate ions for?
Protein production, which is used in growth. A lack of nitrates means protein production is limited, which may lead to stunted growth
What do plants need magnesium ions for?
To make chlorophyll. The leaves may become yellow and growth slows down in a process called chlorosis, if there isn’t enough magnesium.
What are some plant defences against pathogens and herbivores?
Mimicry, drooping, hairy stems, thorns or spikes, bakr, and a tough waxy cuticle.
How does vaccination work?
1) Small amounts of dead pathogens are injected
2) Antigens in vaccine stimulate white blood cells to produce antibodies to destroy the pathogens
3) When exposed to a live version, the body can respond rapidly and create the correct antibody.
What happens in Phase 1, 2, and 3 when testing new drugs?
Phase 1) To work out a safe dosage
Phase 2) To work out side effects
Phase 3) A double blind trial is used. A placebo is used to see how effective the drug actually is
How are monoclonal antibodies made?
1) A mouse is vaccinated to produce antibodies. Spleen cells that form antibodies are collected by operation on the mouse
2) The lymphocytes (spleen cells) are fused with tumour cells (myeloma cells)
3) A hyidoma cell is formed. The tumour cell can divide quickly, but also produce antibodies
4) The cell is cloned in a lab. The antibodies are collected, purified and ready for use
What are some advantages and disadvantages of monoclonal antibodies?
Advantages) Healthy cells aren’t affected, it only binds to the specifically diseased or damaged cells.
Disadvantages) Created more side effects than expected. The mouse antibodies may trigger an immune reaction in humans
Do painkillers help to kill the pathogens?
No. It treats the symptoms of disease.
Can antibiotics kill viruses?
No. Viruses reproduce inside cels, bursting them. Antibiotics only kill bacteria.
What’s the difference between benign and malignant tumours?
Benign form in one place and don’t spread
Malignant invade neighbouring tissues by moving through bloodstream
What is glucose used for?
Respiration, making fruits, making cellulose for cell walls, making proteins, and to store in seeds or as starch.
How is lactic acid removed?
Oxygen is needed to break it down, the amount of oxygen needed is known as the oxygen debt. Blood flowing through the muscles transports lactic acid to the liver, where it’s converted back to glucose.