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Question 1

How do cells transfer energy, and what is the formula?

Answer 1

Cells transfer energy by respiration
glucose+oxygen—————-> =carbon dioxide+water +(energy)
light

Question 2

Where does respiration happen?

Answer 2

In the mitochondria

Question 3

How does glucose get into your cells?

Answer 3

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.

Question 4

How does oxygen get in your cells?

Answer 4

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.

Question 5

Word equation for anaerobic respiration?

Answer 5

Glucose—–> lactic acid+ (energy)

Question 6

Why is aerobic better?

Answer 6

Produces more energy per glucose molecule

lactic acid can cause painful cramps

Question 7

What is the word equation of fermentation?

Answer 7

Glucose—–>ethanol +carbon dioxide

Question 8

What is biotechnology?

Answer 8

Use of biochemical processes or organisms to create useful products.

Question 9

How is bread made?

Answer 9

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

Question 10

Making cider (same process for wine and beer too)

Answer 10

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

Question 11

How do plants and algae make their food

Answer 11

Plants and algae make their food using raw materials

Question 12

How have plants adapted for photosynthesis

Answer 12

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.

Question 13

How does water get into a plant

Answer 13

Water diffuses into the root hair cells and then transported through xylem.

Question 14

Leaf structure

Answer 14

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

Question 15

How do gases get in and out of the leaf

Answer 15

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

Question 16

Different layers of a leaf

Answer 16

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

Question 17

Testing leaves for starch

Answer 17

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

Question 18

Which factors affect the rate of photosynthesis

Answer 18

Light intensity, carbon dioxide and temperature

Question 19

How does light intensity affect the rate of photosynthesis

Answer 19

The higher the light intensity, the faster the rate of photosynthesis. It will get faster until it reaches its maximum rate

Question 20

How does carbon dioxide affect the rate of photosynthesis

Answer 20

Greater the concentration of carbon dioxide, the faster the rate of photosynthesis to some extent

Question 21

How does temperature affect the rate of photosynthesis

Answer 21

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.

Question 22

What minerals do plants need

Answer 22

Nitrates-contain nitrogen for healthy growth
magnesium- for making chlorophyll
potassium- for healthy flowers and leaves
phosphates-contain phosphorous for healthy roots

Question 23

Where do plants get minerals from

Answer 23

Plants get the minerals they need from the soil, they are absorbed into root hair cells and transported throughout the plant through xylem tubes

Question 24

Different mineral deficiencies

Answer 24

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