Grade 9 - Unit 4 - Photosynthesis, Cellular Respiration & Enzymes

Question 1

What organelle is used in Photosynthesis?

Answer 1

Chloroplasts (Which contains the chemical for Photosynthesis, Chlorphyll)

Question 2

Why do plant cells have cell walls, but animal cells don’t?

Answer 2

Plants don’t have bones, so they need another way of staying upright to reach the sunlight, which is what cell walls are used for

Question 3

What chemical is used in Photosynthesis?

Answer 3

Chlorphyll

(Which is located inside the organelles, Chloroplasts)

Question 4

What is the formula for Photosynthesis?

Answer 4

6 Water + 6 Carbon Dioxide —> 1 Glucose + 6 Oxygen
6 H2O + 6 CO2 —> C6H12O6 + 6 O2

Light energy is used to transform it

Question 5

Where is the stomata located and why?

Answer 5

The stomata is located on the bottom of leaves to keep them in the shade and prevent sunlight from evaporating too much water

Question 6

What controls when the stomata opens and closes?

Answer 6

2 guard cells on either side

Question 7

What are the stomata used for?

Answer 7

Gas Exchange, the stomata open to collect carbon dioxide and oxygen, however risk losing water in the process

Question 8

What is the cuticle?

Answer 8

A waxy, protective covering on the plants. They are hydrophobic to prevent water loss, and they keep out unwanted substances

Question 9

When are the stomata open?

Answer 9

During the day due to photosynthesis, and they close during the night

Question 10

What are the function of the roots?

Answer 10

• Anchor the plants in the ground
• Store food
• Collect Water and minerals (tiny root hairs absorb most of it)

Question 11

What are transport tissues?

Answer 11

They appear as veins on the leaves, and are also in the roots and the stem. Vascular Tissue transports water, minerals and glucose throughout the plant. There are 2 types of Vascular tissue, Xylem and Phloem

Question 12

What is the Xylem?

Answer 12

Xylem is a transport tissue in the plant which distributes water & dissolved minerals from roots to leaves. Nutrients only go upwards

Question 13

What is the Phloem?

Answer 13

Phloem is a transport tissue in the plant which distributes sugars from photosynthetic cells in the leaves to living cells throughout the plant. This glucose goes both directions.

Question 14

What energy is used in Photosynthesis?

Answer 14

Light Energy

(Abhinav somehow took 4 tries to figure this out)

Question 15

What organelle is responsible for cellular respiration?

Answer 15

The Mitochondria

(is the powerhouse of the cell)

Question 16

What energy is produced by cellular respiration?

Answer 16

ATP

Question 17

What does ATP and ADP stand for?

Answer 17

Adenosine Triphosphate and Adenosine Diphosphate

(this isn’t that important if you don’t want to memorize it)

Question 18

What is the purpose of ATP?

Answer 18

To store energy

Question 19

How does the ATP cycle work?

Answer 19

When energy is needed, a phosphate is broken off of an ATP molecule, turning it into ADP. When food is eaten, it is converted to a phosphate molecule and connected back onto the ADP to turn it back into ATP

There’s a great image on the slides that you can look at, but i can’t put it on here because Brainscape is blegh also the thingy is on slide 5

Question 20

What is the formula for Cellular Respiration?

Answer 20

Glucose + 6 Oxygen ——> 6 Carbon Dioxide + 6 Water
C6H12O6 + 6O2——> 6CO2 + 6H2O

Generates ATP
This is also the reverse of the Photosynthesis formula, which makes it easier to memorize

Question 21

What is the Cellular Carbon Cycle?

Answer 21

The Cellular Carbon Cycle is a cycle of photosynthesis and cellular respiration in plants. They generate Glucose and Oxygen, and then consume it to create Energy, Carbon Dioxide and Water. They use this Carbon Dioxide and Water to Photosynthesize again, and then repeat the process

There’s a great image on the slides that you can check out, but I can’t put it on here because Brainscape is blegh also its on Slide 18

Question 22

What does a cell need energy for?

Answer 22

• Growth & repair
• Transport
• Reproduction
• Synthesis of molecules
  (these are just some examples from the slides)

Question 23

What is Glycolysis?

Answer 23

Glycolysis is the process of the splitting a glucose molecule. This occurs in the cytoplasm of all cells (every organism). 2 ATP is made during Glycolysis, which is a little. Glucose is broken down further, however this happens in different ways, depending on if oxygen is present or not.

Question 24

What is Anaerobic Respiration?

Answer 24

Anaerobic Respiration occurs after Glycolysis, if no oxygen is present. Also known as fermentation, it occurs in the Cytoplasm and makes a small amount of ATP. It creates Carbon Dioxide and lactic acid or alcohol and it only partially breaks down the glucose. It can be in the form of either Alcoholic Fermentation or Lactic Acid Fermentation

Question 25

What is Aerobic Respiration?

Answer 25

Aerobic Respiration occurs after Glycolysis, if oxygen is present. It occurs in the mitochondria and makes a lot of ATP. It completely breaks down Glucose and also creates carbon dioxide and water. This is also literally just basic cellular respiration that we’ve been learning about.

Question 26

What is Alcoholic Fermentation?

Answer 26

Alcoholic Fermentation is a form of Anaerobic Respiration, which occurs in yeast and bacteria. CO2 and alcohol is made as a result. Shockingly, Beer and Wine are made using this.

Question 27

What is Lactic Acid Fermentation?

Answer 27

Lactic Acid Fermentation occurs in some Bacteria and animals and makes Lactic Acid (Surprisingly). In animals, it occurs as a result of tiring exercise, or when a burst of energy is needed. This results in a burning sensation or fatigue, such as when you work out.

Question 28

Idk where else to put this put if you want a better explanation for Glycolysis and Anaerobic and Aerobic Respiration and stuff

Answer 28

You should check out the thingy on the slides. Its an image on slide 7 and its way better than whatever garbage I wrote down

Question 29

What is the indent in the enzyme, where the enzyme and substrate bond, called?

Answer 29

The Active Site. Each Enzyme has an active site that is molded to its specific substrate

Question 30

What happens when an enzyme denatures, and how does it happen?

Answer 30

When an enzyme denatures, it is completely unusable, and cannot be repaired. It happens when an enzyme is in an environment that is too far from its ideal pH and temperature

Question 31

What does the optimal pH and temperature for enzymes mean?

Answer 31

The specific pH and temperature that the enzyme works most efficiently in. It varies between different enzymes

Question 32

What is a catalyst ?

Answer 32

A catalyst is something that speeds a process up.In biology, catalysts are called Enzymes and exist to catalyze various reactions, meaning they speed them up.

Question 33

What do enzymes do to substrates?

Answer 33

Depending on the enzyme, substrates can be either broken apart, or bonded together

Question 34

What is substrate concentration?

Answer 34

Substrate concentration is the amount of substrate in a specific area. The more substrate there is, the higher the reaction rate. However if there is too much substrate, the reaction rate of the enzymes can no longer increase, as there are too many substrates and not enough enzymes

Question 35

Can enzymes be reused?

Answer 35

Enzymes are never used up in a reaction

HOWEVER, if they become denatured, they are unusable.

Question 36

What is reaction rate?

Answer 36

The reaction rate is the speed at which the enzymes process substrates. Certain conditions, such as being in the optimal pH and temperature, will allow the reaction rate of the enzymes to increase.

Question 37

What are substrates?

Answer 37

Substrates are molecules such as sugars, proteins and starches that are processed by the enzymes