Biology- key stuff
- Created by: Splash Heslin
- Created on: 06-05-15 20:15
Osmosis/ diffusion
Diffusion- net movement of particles (low to high conc.), down conc. gradient.
Osmosis- diffusion of water (dilute to more conc.), through partially permable membrane.
- Hypertonic- shrivelled.
- Isotonic- normal for animals
- Hypotonic- bursting, normal for plants.
Active transport- movement of substances agaisnt conc. gradient, using energy (low conc. to high).
ONLY ACTIVE TRANSPORT USES ENERGY!!!!!!!
Mitosis/ meiosis
Mitosis- 1 stage process: (Diploid)
- a copy of each chromosome made
- cell splits in two
- produce 2 identical daughter cells
NO variation!!!
Meiosis- 2 stage process: (Haploid)
- a copy of each chromosome is made
- cell splits in two
- cells split in two again
- produce 4 gamete sex cells
There IS variation!!!!
Tissues
ANIMAL
- muscular- contract to bring movement
- glandular- produce/ release enzymes + hormones
- epithelial- covers body/ organs. PLANT
- epidermal- covers surface of plant
- paliside mesophyll- chloroplast (photosynthasis)- top layer
- spongy mesophyll- big air spaces + surface area- diffusion.
- xylem- transports water
- phloem- transports sucros TUMOURS
- Benign- single, not affect other tissues, can be life threatning.
- Maligant- (cancer), spreads (blood streme).
- Causes: carcinogens, ionising radiation, virus infections.
Lipids, proteins, carbs
Lipids: Lipase
- fat- source of energy -nuts
- test- ethanol (milky white) -cream
- Made from: glycerol + fatty acids -butter Proteins: Protease
- Hormones, enzymes, antibodies -meat
- Enzymes denature (too hot, wrong pH) -pulses
- Test: biurets solution (cloudy white) -cheese
- Made from: amino acids Carboydrates: Carbohydrase
- Long lasting energy -banana
- Test: iodine (black) -sugar
- Made from simple sugars -bread
Ventilators
Postitve: forces air into lungs (to infalte), pressure stops to deflate.
Advantages: portable, used in operations, patients can move, simple.
Disadvantages: tube inserted into trachea, need source of gas.
Negative:air pumped into chamber 2 cause vaccume. IRON LUNGS
Advantages: used to treat polio, patient can talk, patients can cough.
Disadvantages: patients cannot move about, not portable, hard to acess patientss, can cause blood in abdomen
Respiration
Energy used for: growth/ repair; active transport, heat generation, making proteins.
Aerobic: release large amount of energy in cells in presence of oxygen
glucose + oxygen -> carbon dioxide + water +energy
Anaerobic: release small amount of energy in cells in the absence of oxygen.
glucose -> lactic acid + energy
Blood Vessels
Artery: brings blood away from the heart.
- High pressure and oxygen
- Thick walls
Vein: brings blood back to the heart.
- low pressure
- Valves
- Thin walls
Capillary: links arterys and veins.
- low pressure
- allows diffusion of sudstances
Parts of the blood
Platelets: helps blood clot (fibrogen to fibrin)
Red blood cells: picks of oxygen from lungs and carries to the body (haemoglobin).
White blood cells: bodies defences systeem. (antibodies and antitoxins).
Plasma: waste stuff carried around body. (urea, CO , digestive system)
Nervous System key words
Central nervous system: brain and spinal cord
Neurotransmitters: chemiicals that diffuse across the synapse.
Reflex: automatic response of nerous system to stimuli, uncontious.
Synapse: gap between neurons where the transmition of info is chemical, not electrical.
------------------------------------------------------------------------
Stimulus response pathway: stimulus -> receptor -> sensory neurons -> coordinator -> motor neurone -> effector -> response
The brain
Cerebral Cortex: concerend with consciosness, intelligence, memory, and language.
Cerebellum: concerned mainly with coordinating muscualr activity and balance.
Medulla: concerenced with unconscious activites: heartbeat, breathing, movement of gut.
Hypothalmus: regulation of body functions (thermoregulation)
Pituitary Gland: produces chemical messags(hormones) which control reactions in the body.
Homeostasis key words
Homeostatis: maintence of constant internal body conditions.
Hormone: chemical producaed in glands to carry chemical messages.
Coordinators: brain, spinal cord, pancreas.
Liver: organ that produces bile
Kidney: filters blood- removes ures, excess salts and water.
Urea: waste product formed by breakdown of amino acids
Selective reabsorbtion: the kidneys selectively reabsorb only those molecules which the body needs back in the bloodstream.
Thermoregulatory: in brain controls/ monitors body temperature.
Diabetes: failing to regulate blood sugar levels.
Diabetes
Type 1:pancreas not producing enough inculin = high blood glucose levels
- Genetics
- Control: transplant, inject insulin
Type 2: body cells not responding to insulin.
- age, obesity.
- Control: loose weight, drugs, exersize
-------------------------------------------------------------------------
Insulin: hormone controlling sugar levels
Treating disease
MMR vacination: measels, mumps, reubella.
Heard immunity: if most people are immune to a diease in a community then it cant spread, and it will die.
White blood cells:
- Ingest pathogen
- Antibodies made for specific antigen on pathogen to destroy it.
- Antitoxins counteract toxins from pathogens.
Anitbiotics: chemical compund killing bacteria.
Painkillers/ drugs: relieve symtoms but not killing pathogen.
Antiseptic: kills microoganisms in the enviroment.
Growing baterica
Keeping it uncontaminated:
- sterilize petri dish + agar
- sterilize incoulating loop (flame)
- tape the lid down
- place it upside down (condesation)
Conditions:
- 25 degrees (not hotter as harmfull bacteria may grow)
- culture medium: nutrients, carbohydrates, minerals. (agar jelly)
- dont tape lid all the way round (oxygen needs to get in)
Photosynethsis
carbon dioxide + water -> glucose + oxygen
6CO + 6H O -> C H O + 6O
Photosynthesis ingrediants:
- Carbon dioxide
- Light
- Water
- Chlorophyll.
Limiting Factors: light, temperature, carbon dioxide
Testing for starch: iodine goes blue/ black.
- no starch in plant left in the dark as it has used it all up to convert to energy (glucose)
Germination
Auxin: plant horone controlling plant responses.
- Phototropism
- Gravitropism
- Negative
- Positve
Plant shoots grow towards light, against the force of gravity.
Plant roots grow towards moisture, in the direction of gravity.
Auxin spreads to the dark side
Shoot grows more on the side with the most auxin
Root grows more on the side with the least auxin.
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