(P1+P2) Topic 1: Key Concepts Flashcards
Calculation to convert metres (m) to millimetres (mm)
x1000
Calculation to convert millimetres (mm) to micrometers (μm)
x1000
Calculation to convert micrometers (μm) to nanometres (nm)
x1000
Calculation to convert nanometres (nm) to picometres (pm)
x1000
Calculation to work out total magnification
Total magnification = eyepiece lens x objective lens
Name the components of a plant cell (7 things)
Cell wall
Cell membrane
Vacuole
Nucleus
Mitochondria
Cytoplasm
Chloroplast
Name the components of an animal cell (5 things)
Ribosomes
Mitochondria
Cytoplasm
Nucleus
Cell membrane
What does the nucleus contain
DNA
What do mitochondria do
Respiration and release energy
What does the cell wall do
Strengthens the cell
What do chloroplasts do
Photosynthesis
What do ribosomes do
Synthesise protein
What does the cell membrane do
Controls what goes in and out of the cell
Name the 7 nutrients
Minerals
Vitamins
Protein
Carbohydrates
Fats
Fibre
Water
What is the food test for starch
Iodine
Goes blue-black in starch
Orange in no starch
What is the food test for sugar
Benedict’s +heat (90°)
Yellow orange/ brick red = sugar present
Blue = no sugar present
Food test for fat
Ethanol + shake
Milky white = fat present
Clear and colourless = no fat present
Food test for protein
Biuret
Purple = protein present
Blue = no protein present
What is the cell wall made of
Cellulose
What is a catalyst
Something that speeds up a reaction
What is an enzyme
A biological catalyst
What does denatures mean
When a cell can’t work anymore due to too high or low temp, too high or low pH, etc
What is physical digestion + examples
Breaking large pieces of food into smaller pieces e.g chewing, stomach churning
What are enzymes made out of
Amino acids
Factors that effect enzymes (4 things)
Temperature
pH
Surface area
Concentration
What is chemical digestion and why does it occur
Breaking down large molecules into smaller molecules. It requires enzymes. Molecules need to be small do they can be absorbed through the gut wall into the blood
Why does bile emulsify fats
Because water and fat don’t mix
Define diffusion
The movement of a substance from an area of high concentration to an area of low concentration, down the concentration gradient
What are the factors that affect diffusion (4)
Temperature
surface area to volume ratio
thickness of membrane
concentration gradient
What is Fick’s Law
Rate of diffusion ∝ concentration gradient x surface area / thickness of membrane
∝ means approximately
What is facilitated diffusion
Special diffusion, carrier proteins let large molecules in
Define osmosis
Diffusion of water across a partially permeable membrane
Define active transport
Movement of ions against the concentration gradient. This requires energy
Calculation for image size
Image size = actual size x magnification
