Organisation Flashcards
True or false, the spongy mesophyll is a tissue
True
What is the purpose of the waxy cuticle on the top of the leaf
To reduce water loss
(It is a thin layer of lipids that the water can’t get through)
Where are most stomata located in a leaf and why
Underside
To prevent water loss through evaporation as it is shaded so cooler
Why is the upper epidermis transparent
Allow light to pass through to reach palisade cells for photosynthesis
Where are the epidermis located in the leaf
Top (upper)
Bottom (lower)
(Single layer of cells to protect against water loss)
What is the upper and lower epidermis
Single layer of cells to protect against water loss but transparent to still let light pass through
True or false, the waxy cuticle and epidermis both protects against water loss
True
Waxy cuticle (waterproof layer) is very outer layer of leaf followed by epidermis (single layer of cells)
What is transpiration
Movement of water from roots to leaves through xylem and then the loss of water by evaporation through the stomata
4 factors affecting rate of transpiration
Humidity
Temperature
Wind
light
How humidity affects rate of transpiration
More humid= slower rate so less water loss
(When it’s humid there’s already lots of water in the air so less of it evaporates from the leaf)
How light affects rate of transpiration
Higher light intensity increases rate as stomata open wider for more CO2 to be let in for photosynthesis but in turn water is lost
How wind affects rate of transpiration
More wind increases rate
Water vapour is removed quickly by wind so concentration gradient is steeper
How temperature effects rate of transpiration
Higher temperature increases rate because water evaporates faster in higher temperatures
What is translocation
Movement of dissolved sugars from leaves to rest of plant through phloem
Importance of transpiration in plants
Provides water to cells to keep them turgid
Provides water to cells for photosynthesis
Transports mineral ions to leaves
Importance of translocation in plants
Moves dissolved sugars produced in photosynthesis to other parts of plant allowing respiration, growth and glucose storage
When guard cells are turgid are the stomata open or closed
Open
(When they are turgid they have lots of water so swell up and curve away from each other so open the stomata)
When they are flaccid (lack of water) the stomata close
Is a leaf a cell, tissue or organ
Organ
True or false, layers of cells in a plant are tissues e.g the upper epidermis is a tissue
True
(Tissue = group of cells with similar structure and function)
What colour does iodine turn to if starch is present
Blue/ black
What colour is iodine solution
Orange
How many test tubes do you need for the enzymes RPA (effect of analyse on PH)
3
(One for starch solution, one for analyse solution, one for buffer PH solution)
What equipment do you need for the effect of enzymes (analyse) on PH RPA
Spotting tile
3 test tubes
Stirring rod
Iodine solution
2cm cubed buffer solution with different PH
2cm cubed analyse solution
2 cm cubed starch solution
Water bath at 30 degrees
Stopwatch
First stage of effect of enzymes on PH RPA
Take a spotting stile and use a pipette to add one drop of iodine solution (orange) to each well (hole)
What do you do once each well in the spotting tile had a drop of iodine solution in
Take 3 test tubes and use a pipette to measure 2cm cubed of starch solution, analyse solution and buffer PH solution and add each different solution to each test tube
What temperature should the water bath be for enzymes RPA
30 degrees
Why do the test tubes for enzymes RPA need to be placed in a 30 degree water bath for 10 mins
Allows them all to reach the correct temperature so analyse enzymes are at optimum temperature to react and therefore it is only the PH that effects the reaction, not temperature
What is a tumour
Lump of cells formed by uncontrolled cell division and growth.
A tumour is a lump of cells formed by
Uncontrolled cell division and growth
What is a carcinogen
Chemical/ other agent that causes cancer
Name for chemical/ other agent that causes cancer
Carcinogen
Which type of tumour is cancerous
Malignant
Which type of tumour isn’t cancerous
Benign
Which type of tumour invades other parts of the body
Malignant
Describe a malignant tumour
Type of tumour formed by uncontrolled cell division that grows quickly and invades neighbouring tissues and can spread to other parts of the body through the bloodstream (is cancerous)
How can a malignant tumour spread to other parts of the body
Bloodstream
Describe a benign tumour
Not cancerous. Formed from uncontrolled cell division but grows slowly, doesn’t invade other parts of the body and can easily be removed
Where does a benign tumour usually grow
Within the cell membrane
What type of process causes the cells that form a tumour to divide
Mitosis
Where is bile produced, stored and added
Produced by liver, stored in gall bladder, added to small intestine
2 functions of bile (produced in liver, stored in gall bladder, added to small intestine)
Emulsifies fats- breaks them down into smaller molecules to increase surface area for lioase enzymes to work on
Neutralises acid from stomach- creates optimum ph for enzymes
2 key adaptations of xylem
Thick walls strengthened by lignin to stop water bursting through
Made of dead cells joined together with no end walls to form a continuous hollow tube
2 adaptations of phloem
Companion cells attach to each sieve plate to provide energy for transportation of dissolved sugars
Made up of sieve tubes
What are the 4 food tests
Iodine (starch) orange to black/ blue
Benedict’s (glucose) blue to red
Biuret (protein) blue to purple
Ethanol (fats) colourless to cloudy
What is used to test for protein
Biuret solution
What is used to test for glucose
Benedicts solution
What is used to test for starch
Iodine solution
What is used to test for fats
Ethanol
Colour change of Biuret solution if protein is present
Blue to purple
Colour change of iodine solution if starch is present
Orange to blue/ black
Colour change of Benedict’s solution if glucose is present
Blue to red
Colour change of ethanol if fats are present
Colourless to cloudy
If what is present ethanol will turn from what to what
Fats, colourless, cloudy
If what is present Benedicts solution will turn from what to what
Glucose, blue, red
If what is present iodine will then from what to what
Starch, orange, blue/ black
If what is present biuret solution will turn from what to what
Protein, blue, purple
Function of epithelial tissue in stomach
Covers inside and outside of stomach
What is a stent
Mesh like cage that inflates in order to open up the coronary artery to allow more blood carrying oxygen to flow and be supplied to the heart
Risk of infection and blood clotting
What is a statin
Drugs that reduce cholesterol levels to reduce build up of fatty deposits in coronary arteries making room for more blood to flow through so more oxygen can be supplied to the heart
No need for surgery, may have side effects like headaches and sickness
Which arteries supply oxygen for respiration
Coronary arteries
Which ventricle has thicker muscle wall and why
Left ventricle
To pump the blood away from the heart at a high pressure to get the whole way round the body
Generally do arteries carry oxygenated or deoxygenated blood
Oxygenated to get to the rest of the body (except the pulmonary artery)
