Topic One Flashcards
How do you calculate a microscope magnification
You multiply the eyepiece lens by the objective lens
What was magnification of Hookes microscope
30x
What is resolution in microscope
The smallest distance between two points that can still be seen as two points
What is an electron microscope
A microscope that uses beams of electrons to pass through a specimen to build an image. These have really high magnification which means that the resolution is very clear
How many micro meters in 1 mm
1000 micro metres(µm)
How many nanometres in 1 mm
1,000,000
How many mm in 1metre
1000mm
How many pico meters in 1 mm
1,000,000,000
Robert Brown 1828
Examined cells from a surface of a leaf and noticed that they each contain a small blob. He called this the nucleus
A cell with a nucleus
Eukaryotic
What does the cell membrane do
Controls what enters and leaves the cell on separate one cell from another
What happens in the cytoplasm
Where the cells activities and reactions occur
What do mitochondria do
This is where aerobic respiration occurs and they provide energy
What does the nucleus do
The nucleus controls the cell and has DNA inside of it
What do ribosomes do
These make new proteins for a cell
What do animal cells have in them
Nucleus, cell membrane, cytoplasm, ribosomes, mitochondria.
What do plant cells have in them
Nucleus, cell wall, cytoplasm, cell membrane, chloroplast, vacuole, mitochondria, ribosomes.
Specialised cells
Are adapted to their function is
How are the cells that line the small intestine adapted for digestion
They have microvilli which have lots of folds that increase the surface area of the cell which means that the absorption of molecules is faster.
The walls of the small intestine have muscles to squeeze food along.
These are adapted by having lots of mitochondria because they need energy
How are pancreatic cells adapted for digestion
They have lots of ribosome is so that they can produce enzymes which are proteins
How are gametes specialised for reproduction
Gametes just have one copy of the types of Chromosome. This means they are haploid cells, and can fuse to make a complete diploid egg
How are the oviduct cells adapted for fertilisation
They have hair like cilia which wave from side to side that carry the egg along the oviduct.

Cell without a nucleus
Prokaryotic
What does the cytoplasm of a bacteria cell contain
One large loop of chromosomal DNA and smaller loops of DNA called plasmids which control a few of the cells activities. Bacteria cells don’t have mitochondria or chloroplasts
What do bacteria cells have in them usually
Flagellum for movement
Plasmids and chromosomal DNA
Slime coat for protection
Flexible cell wall that’s not made out of cellulose for support
Cell membrane
Cytoplasm that has ribosomes in it
What does protein breakdown into
Amino acids
What does starch breakdown into
Glucose
What do lipids breakdown into
Fatty acids and glycerol
Describe an enzyme
Enzymes are biological catalysts that increase the rate of reactions. They work on substances called substrate and produce products. Enzymes are proteins.
Amylase
Found in saliva and the small in testing and breaks down starch to small sugars like maltose
Catalase
Found in most cells but especially in liver cells and breaks down hydrogen peroxide made in cell reactions to water and oxygen
Carbohydrase
Breaks down carbohydrates into glucose
Protease
Breaks down proteins into amino acid
Lipase
Breaks down lipids into glycerol and fatty acids
What is the test for starch
Iodine turns blue or black if it’s positive for starch from its original colour of orange
This is a qualitative test
What is the test for sugar
Benedict’s solution turns green or orange or red depending on the amount of reducing sugar from its original colour of blue
This is a semi qualitative test
What is the test for protein
Biuret turns different shades of violet depending on the quantity of protein in the substance this is a semi qualitative test
Biuret is blue originally
What is the test for lipids or fat
The emotion test – dissolve fats and ethanol and then put into water it will turn cloudy if the fats are present
What is calorimetry
When we heat food by burning and measure the energy released to figure out how much energy is in food. Energy transferred is equal to the mass of water x 4.2 x temperature rise
What is a more accurate way of measuring the amount of energy in food
By using a calorimeter that has insulation to have more accurate results
Explain how enzymes work
Enzymes have an optimum temperature and an optimum pH level. They have an active site that is shaped specifically for a substrate to bind with it. Enzymes can either find substrates together or reduce them to smaller pieces. When the substrate fits into the active site this is called the enzyme substrate complex. High temperatures or high pH levels can denature the enzyme so the active site becomes altered. When substrate concentration increases so does enzyme activity
Example of active transport in animals
Glucose gets absorbed into the blood from the small intestine which is from a low to high concentration and uses carrier proteins and energy
Example of active transport in plants
Minerals are absorbed into root hair cells from the low concentration in the soil to the high concentration in the cell so it has a lot of mitochondria to do this
