Biology EOY Topics 1, 2 and 3

chat GPT flashcards from EOY checklist: Topics 1, 2 and 3 IGCSE Edexcel

Characteristics of living organisms

Nutrition, respiration, excretion, response, movement, internal control, reproduction, and growth.

Aerobic respiration word equation

Glucose + oxygen → carbon dioxide + water.

Aerobic respiration symbol equation

C₆H₁₂O₆ + 6O₂ → 6CO₂ + 6H₂O.

Role of respiration

Produces ATP as energy for cells.

Respiring seeds experiment

Measures CO₂ and heat release to show respiration.

Balanced diet

Contains carbohydrates, proteins, lipids, vitamins, minerals, water, and fibre.

Function of nutrients

Carbs for energy, proteins for growth/repair, lipids for energy/insulation, vitamins/minerals for health, fibre for digestion, water for hydration.

Energy needs

Vary with activity, age, and pregnancy.

Food energy experiment

Burn food sample to measure energy content.

Carbohydrate structure

Made of simple sugars; starch and glycogen are complex forms.

Protein structure

Made from amino acids.

Lipid structure

Made from fatty acids and glycerol.

Elements in macromolecules

Carbs and lipids: C, H, O; Proteins: C, H, O, N.

Food tests

Benedict's for glucose, iodine for starch, biuret for protein, ethanol for fat.

Alimentary canal

Includes mouth, oesophagus, stomach, small and large intestines, rectum, pancreas.

Peristalsis

Muscle contractions that move food through the gut.

Levels of organisation

Organelle → cell → tissue → organ → system.

Role of enzymes

Biological catalysts in metabolism.

Digestive enzymes

Amylase/maltase (starch to glucose), protease (proteins to amino acids), lipase (lipids to fatty acids/glycerol).

Enzyme temperature effect

Higher temps increase activity up to optimum, then denature.

Active site shape

Can change with temperature, affecting enzyme function.

Bile production

Made in liver, stored in gall bladder.

Bile function

Neutralises stomach acid, emulsifies fats.

Diffusion

Movement from high to low concentration.

Osmosis

Water moves through semi-permeable membrane.

Active transport

Movement against concentration gradient using energy.

Small intestine adaptation

Villi increase surface area for absorption.

Plasma role

Transports CO₂, food, urea, hormones, heat.

Alveoli adaptation

Large surface area, thin walls, good blood supply for gas exchange.

Thorax structure

Ribs, intercostal muscles, diaphragm, trachea, bronchi, bronchioles, alveoli, pleural membranes.

Ventilation

Diaphragm and intercostal muscles change pressure for breathing.

Blood composition

Red/white cells, platelets, plasma.

Cell organelles

Nucleus, cytoplasm, membrane, wall, mitochondria, chloroplasts, ribosomes, vacuole.

Red blood cells

Biconcave, no nucleus, haemoglobin for oxygen transport.

Heart structure

Chambers, valves, arteries/veins, contracts to pump blood.

Circulatory system

Blood vessels to/from heart, lungs, liver, kidneys.

Blood vessel structure

Arteries (thick, high pressure), veins (valves), capillaries (thin walls).

Heart rate

Increases with exercise or adrenaline.

Diffusion/osmosis experiment

Use living and non-living systems to observe movement.

Stimulus response

Receptor detects, effector responds.

Organs of excretion

Lungs (CO₂), kidneys (urea), skin (sweat).

Urinary system

Kidneys, ureters, bladder, urethra.

Nephron structure

Bowman's capsule, glomerulus, tubules, loop of Henle, collecting duct.

Ultrafiltration

Blood is filtered in Bowman's capsule.

Selective reabsorption

Glucose reabsorbed in proximal tubule.

Kidney roles

Excretion and osmoregulation.

ADH hormone

Regulates water reabsorption in kidney.

Water reabsorption

Occurs in collecting duct.

Urine content

Water, urea, ions.

Diffusion in unicellular organisms

Sufficient due to small size.

Transport in multicellular organisms

Needed due to complexity and size.

Coordinated response

Requires stimulus, receptor, effector.

Nervous vs hormonal control

Nervous is fast and localised, hormones are slower and longer-lasting.

Central nervous system

Brain and spinal cord connected to sense organs.

Reflex arc

Involves sensory neuron, spinal cord, motor neuron.

Impulse transmission

Receptors send impulses via nerves for response.

Neurotransmitters

Transfer signal across synapses.

ATP

Energy currency for cellular activities.

Exercise and heart rate

Increases to supply more oxygen.

Breathing experiment

Measures CO₂ release and breathing rate during exercise.

Adrenaline and insulin

Adrenaline increases heart rate; insulin lowers blood sugar.

Homeostasis

Maintaining stable internal environment.

Skin in thermoregulation

Sweating, vasodilation/constriction control temperature.

Temperature effect on enzymes

High temp denatures, low temp slows reaction.

Coronary heart disease

Risk increased by lifestyle factors.

Smoking effects

Damages lungs, heart, increases disease risk.

Air pollution effects

Sulfur dioxide and CO cause respiratory problems.

Cell nucleus

Contains chromosomes with genes.

Genome

All DNA; gene codes for a protein.

DNA structure

Double helix with base pairs A-T and C-G.

Restriction enzymes

Cut DNA at specific sites.

Ligase enzyme

Joins DNA fragments.

Vectors

Plasmids/viruses insert DNA into cells.

Transgenic definition

DNA from one species inserted into another.

Insulin production

Genetically modified bacteria in fermenters make insulin.

Bacteria features

No nucleus, single-celled.

Pathogens

Disease-causing: bacteria, fungi, viruses, protoctists.

Antibiotic resistance

Bacteria evolve resistance, making infections harder to treat.

Platelets

Help blood clot to prevent loss/infection.

White blood cells

Phagocytes engulf pathogens, lymphocytes produce antibodies.

Vaccination

Triggers memory cells for faster future response.

Stem cells

Can treat diseases, but raise ethical issues.

Variation

Caused by genetics, environment, or both.

Eukaryotic features

Nucleus, membrane-bound organelles (plants, animals, fungi, protoctists).

Prokaryotic features

No nucleus, simple structure (bacteria).

Selective breeding

Choosing parents with traits to produce offspring with desired features.

RNA structure

Single strand, uracil replaces thymine.

Protein synthesis

Transcription makes mRNA, translation at ribosome assembles protein.