dsaf Flashcards
How do cells transfer energy, and what is the formula?
Cells transfer energy by respiration
glucose+oxygen—————-> =carbon dioxide+water +(energy)
light
Where does respiration happen?
In the mitochondria
How does glucose get into your cells?
Digestion breaks down the food, releasing glucose molecules. These molecules are absorbed by the wall of the small intestine and then into your blood stream. The liquid part of your blood called plasma dissolves it.
How does oxygen get in your cells?
When you breathe, air fills the alveoli in your lungs, it then diffuses into your bloodstream. Oxygen is carried by red blood cells. Red blood cells contain haemoglobin, oxygen joins to haemoglobin.
Word equation for anaerobic respiration?
Glucose—–> lactic acid+ (energy)
Why is aerobic better?
Produces more energy per glucose molecule
lactic acid can cause painful cramps
What is the word equation of fermentation?
Glucose—–>ethanol +carbon dioxide
What is biotechnology?
Use of biochemical processes or organisms to create useful products.
How is bread made?
Flour water and yeast are mixed to make dough
dough then kept in warm place to rise (caused by fermentation)
yeast fermenting changes the flour into ethanol+co2 rising dough
dough then baked in oven ethanol evaporates
bubbles of gas further rise the dough
Making cider (same process for wine and beer too)
The apple is crushed to get the plant sugar
Yeast then added in order to ferment sugar
The container then sealed for the prevention of oxygen and microorganisms from entering and creating a reaction
The mixture is left until the process of fermentation complete
the apple solids are removed by filtration
the cider is bottled ready for use
How do plants and algae make their food
Plants and algae make their food using raw materials
How have plants adapted for photosynthesis
Plants have scientifically adapted organs that allow them to obtain all the resources for photosynthesis.
Photosynthesis mainly takes place in chloroplasts in the leaf cells, though a small amount happen in the stem. Leaves and stems are green because they have a green pigment called chlorophyll. Chlorophyll uses light from the sun. The energy transferred from the sun is needed in photosynthesis.
How does water get into a plant
Water diffuses into the root hair cells and then transported through xylem.
Leaf structure
Are thin- allows gasses to diffuse in and out of the leaf
are green -they contain chlorophyll which absorbs sunlight
have a large surface area- to absorb as much light as possible
have veins-these contain xylem which transport water and phloem tubes which transfer glucose
How do gases get in and out of the leaf
The tiny holes (pores) found at the bottom of a leaf are called stomata (singular stoma) their function is to let gases diffuse into and out of the leaf.
Co2 goes in
oxygen+water vapour diffuse out
Different layers of a leaf
Palisade layer is the top layer of a leaf which contain cells packed with chloroplasts and where most of the photosynthesis happens
The spongy layer contains lots of airspace, allowing co2 to diffuse throughout the leaf. Oxygen diffuses out of the leaf
Testing leaves for starch
Take the leaf and put it in boiling water to kill it
put the leaf into a boiling tube of boiling ethanol to remove all the chlorophyll to prevent photosynthesis
wash the leaf with water to remove ethanol
add a few drops of iodine solution onto the leaf
if the leaf has starch, iodine will turn blue-black
Which factors affect the rate of photosynthesis
Light intensity, carbon dioxide and temperature
How does light intensity affect the rate of photosynthesis
The higher the light intensity, the faster the rate of photosynthesis. It will get faster until it reaches its maximum rate
How does carbon dioxide affect the rate of photosynthesis
Greater the concentration of carbon dioxide, the faster the rate of photosynthesis to some extent
How does temperature affect the rate of photosynthesis
In general, the higher the temperature, the faster the rate of photosynthesis. This is because photosynthesis involves enzymes which speed up the reaction as the temperature increases. However, at a certain temp, enzymes stop working.
What minerals do plants need
Nitrates-contain nitrogen for healthy growth
magnesium- for making chlorophyll
potassium- for healthy flowers and leaves
phosphates-contain phosphorous for healthy roots
Where do plants get minerals from
Plants get the minerals they need from the soil, they are absorbed into root hair cells and transported throughout the plant through xylem tubes
Different mineral deficiencies
Nitrate deficiency- have poor growth and older leaves are yellowed
Phosphorous- deficiency- have poor root growth and younger leaves look purple.
Potassium deficiency- Plant has yellow leaves with dead patches
magnesium deficiency- plant leaves are yellowed
