END OF YEAR BIOLOGY

Cells can either be

prokaryotic-single cell and eukaryotes-organisms

What are the diffrences between plant and animal cells

animal cells dont have a cell wall or chloroplasts to do photosynthesis with.

Bacteria

They dont have mitochondria or chloroplasts. they also dont have a nucleus. DNA floats freely in the cytoplasm.

Diffrences between plant and animal cells

animal cells dont have cell walls or chloroplasts.

magnification =

image size/real size

Differation

when a cell changes to become specialised

Sperm cells

repoduction

nerve cells

rapid signalling

muscle cells

contraction

root hair

absorbsion of water and minerals

Phloem and xylem

transporting substances

Organs systems

are organised into organ systems, which work together to form organisms.

Organs

are groups of tissues performing specific functions.

A tissue

is a group of cells with a similar structure and function.

Cells

they make up all living organisms

diffusion

movement of a substance from a region of high concentration to a region of low concentration 

What affects diffusion

The greater the difference in concentration, the quicker the rate of diffusion.

The higher the temperature the faster they will move and mix.

The greater the surface area, the faster the rate of diffusion.

what diffuses in and out of cells

O2 CO2 and glucose

Surface area to volume ratio

find area (length X width)

Find volume (lenght X width X height)

put into ratio

how the small intestine and lungs in mammals, and roots and leaves in plants, are adapted for exchange of substances.

they all have large surface areas and a thin membrane.

What is osmosis?

It is the movement of water across a semipermeable membrane from high concentration

how to investigate the effect of salt or sugar solutions on plant tissue.

prepare sugar solutions with a range of concentrations

set up one with distilled water to act as the control

cut up potato and measure the mass of each one

leave the potato in each of the solutions for 24 hours

After 24 hours take the potatoes out of the solution and measure their mass

calculate percentage change in mass

change in mass= (mass at end - mass at start)/ mass at start X 100

Active transport

movement of cells from low to high concentration.

photosynthisis

co2+water → glucose+o2

Lactic acid

makes muscles hurt is toxic, oxygen is used to get rid of it

AEROBIC 1

releases lots of energy, uses o2, produces c02 and h2o, long time, low intensity, C6H12O6+O2→CO2+H20,

ANAEROBIC

RELEASES LESS ENERGY, SHORT TIME, HIGH INTENSITY, GLUCOSE→LACTIC ACID, HAPPENS IN MUSCLE CELLS

ALVIOLI ADAPTATIONS

THIN CELL WALLS, LARGE SURFACE AREA

OXYGEN DEBT

The amount of oxygen required to remove the lactic acid, and replace the body's reserves of oxygen

LIMITING FACTORS

A FACTOR THAT LIMITS PHOTOSYNTHESIS PRODUCTS OF RESPIRATION WATER AND CO2

Layers of plant tissue

waxy cuticle-stops water from evaporating out of leaf

palisade layer- contains chloroplasts , this is where most photosynthesis takes place.

spongy layer- allows teh interchange of gases during photosynthesis.

Guard cells-control what goes in and out of the leave

affect of co2 on photosynthesis

as co2 increases so does photosynthesis until something else becomes a limiting factor.

What do alveoli do

carry out gas exchange gas exchange

Adaptations of an alveoli

thin walls

good blood supply

large surface area

What are enzymes

Enzymes are catalysts. They speed up useful chemical reactions in the body.

Enzymes need a specific pH and temperature to work. If they are not in this environment they will

denature. this means that the active site changes and it no longer fits the substrate

Starch is broken down into

sugars

Protiens is broken down into

amino acids

Lipids are broken down into

glycerol and fatty acids

Lipids is broken down by

Lipase

Starch is broken down by

Amylase

Where is bile produced

in the liver

where is bile stored

in the gallbladder

Where is bile released

in the small intestine

what does bile do

It neutralises the stomach acid acid emulsifies fats

Salivary glands

Produce amylase in saliva

Oesophagus

Muscle that transports food to stomach

Liver

Bile is produced here

Stomach

Pummels food Produced protease Produced hydrochloric acid-To kill bacteria and give right pH for protease

Gallbladder

Bile is stored

Pancreas

Makes Protease, amylase, lipase

Large intestine

excess water is absorbed

small intestine

digested food is absorbed into the blood

Test for sugars

Benedict’s test Positive-Blue to green to yellow to red

Test for starch

iodine Positive- Orange to black or blue

Test for Proteins

biuret Positive- Blue to purple

Test for lipids

Sudan 3 Positive- Red layer

Lock and key model

every active site will have a substrate that will fit perfectly in it .

Digestive system

Digestive system

Method reqired praq limiting factors

* Ensure the water is **well aerated** before use by **bubbling air through it**
* This will ensure oxygen gas given off by the plant during the investigation form **bubbles** and **do not dissolve in the water**
* Ensure the plant has been **well illuminated** before use
* This will ensure that the plant contains all the enzymes required for photosynthesis and that any changes of rate are due to the independent variable
* Set up the apparatus in a **darkened room**
* Ensure the pondweed is submerged in **sodium hydrogen carbonate solution (1%)** – this ensures the pondweed has a controlled **supply of carbon dioxide** (a reactant in photosynthesis)
* Cut the stem of the pondweed **cleanly** just before placing into the boiling tube
* Measure the volume of gas collected in the gas-syringe in a **set period of time** (eg. 5 minutes)
* **Change the independent variable** (ie. change the light intensity, carbon dioxide concentration or temperature depending on which limiting factor you are investigating) and repeat step 5
* Record the results in a table and plot a graph of volume of oxygen produced per minute against the distance from the lamp (if investigating light intensity), carbon dioxide concentration, or temperature

aerobic respiration is

 glucose + oxygen → carbon dioxide + water + energy.