Biology Paper 1

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Cards (104)

What is Osmosis?
Movement of water particles from a high water concentration to a low water concentration through a semi permeable membrane
Define prokaryotic 
A smaller cell that does not have a nucleus, the DNA is loose in the cytoplasm or in plasmids
Active Transport 
Movement of particles from a low concentration to high concentration against a concentration gradient
Diffusion
Movement of particles high to low concentration down a gradient
Define eukaryotic
A larger cell with a nucleus containing DNA
Stem Cell 
An undifferentiated cell that can differentiate into other types of cells
Define Resolution 
How well we can distinguish between 2 seperate points that are close together
How is a sperm cell adapted? 
It has a long tail to help it swim to the egg. It contains lots of mitochondria to provide energy
How are nerve cells adapted?
It carries electrical signals to parts of the body. The cells are long and have branched connections at their ends to form a network through the body
How are root hair cells adapted?
On the surface of plant roots which grow into long hairs. This gives the plant a large surface area for absorbing water and mineral ions
How are muscle cells adapted?
They contract quickly, these cells are long and contain lots of mitochondria for energy needed for contraction
How are Phloem and Xylem cells adapted?
They transport substances such as food or water and mineral ions to plants
Define Mitosis  
A type of cell division used for growth and repair of tissues. Also used to form embryos
Define Differentiation 
The process by which cells become specialised to perform their function
Define Magnification
How much bigger an image is compared to real life
Equation : actual size = image/ magnification
What is the method for the Microscope practical? 
Put a drop of the specimen on a microscope slide
Add a drop of water in the middle of a clean slide
Cut up an onion and seperate it out into the layers. Use tweezers to peel off the epidermal tissue from the bottom of one of the layers
Using the tweezers place the epidermal tissue into the water on the slide
Add a drop of iodine solution stain to highlight objects in the cell
Place a cover slip on top,stand the cover slip upright to the water droplet CAREFULLY to prevent air bubbles
How do you set up a light microscope?
Clip the prepared slide onto the stage
Select the lowest power objective lens
Use the coarse focus wheel and to move the stage up to just below the objective lens
Look down on the eyepiece. Use the coarse wheel to move the stage downwards till image is roughly in focus
Adjust the focus with fine focus wheel until there is a clear image of what’s on the slide
If slide needs to be seen in greater magnification, change to the high power objective lens
What do white blood cells do?
Ingest pathogens and produce antibodies
What is the use of the epidermal tissue?
Covers the whole plant
What does palisade mesophyll tissue do?
It is the place where most photosynthesis takes place
What is the spongy mesophyll tissues function? 
Has big air spaces to allow gases to diffuse in and out of cells
What is the function of the Xylem and Phloem?
Transports water, mineral ions and dissolved sugars around the plant
What is the function of the Meristem Tissue? 
Is able to differentiate into lots of different types of plant cell, letting everything grow
What does the Phloem do?
It transports dissolved sugard made in the leaves for immediate use or for storage
Its made out of elongated living cells with small pores in end walls to let cell sap flow
What does the Xylem do?
Transport water and minerals from roots to leaves
Its made out of dead cells joined end to end with no end walls and are strengthened with a material called lignin
What is the function of Red Blood Cells?
What is their shape?
Their job is to carry oxygen from the lungs to all the cells in the body
Their shape is bioncave disc to give a large surface area for absorbing oxygen
They have no nucleus so there’s more space for oxygen to be carried
What is a communicable disease?
A disease that is spread between people and is caused by a pathogen
What is a non communicable disease?
A disease that can’t be spread and is not caused by a pathogen
Define health
State of physical and mental wellbeing
How do you test for sugars?
Add a few drops of Benedict’s solution
Heat a water bath at 75 degrees for 5 mins
If it stays blue, no sugar if present
If it turns red there is a low concentration of sugar
If it turns green there is a high concentration of sugar
What are the enzymes and what do they break down and produce?
Amylase breaks starch into glucose
Lipase breaks down lipids into fatty acids and glycerol
Protease breaks down proteins into amino acids
How to test for proteins?
Add a few drops of Biuret solution
If the solution stays blue no protein is present
If it turns purple/ lilac protein is present
How to test for lipids ( fats)?
Add a few drops of ethanol to the sample
If no lipids are present it will remain colourless
If a white cloudy emulsion forms then lipids are present
What are the organs in size from smallest to biggest?
Cell
Tissue
Organ
Organ system
What is a cell?
Basic building block of all organisms
What is a tissue?
A group of similar cells working together to perform a specific function
What is an organ? 
A group of different tissues that work together to perform a specific function in the body.
What is an Organ System?
A group of organs working together
What is a risk factor and which risk factors can cause disease? 
Things that are linked to an increase in a likelihood that a person will develop a certain disease in their lifetime
Drinking and smoking
What are the 2 types of cancer?
Benign - tumour grows until theres no more room and isn’t cancerous
Malignant - tumour spreads across healthy tissues and is fatal