Topic 2 (Homeostasis)

Question 2

What is homeostasis?

Answer 2

he internal stability that all organisms maintain to survive, through biochemical processes.

Question 3

What process stores energy in plants?

Answer 3

Photosynthesis.

Question 4

Photosynthesis word equation?

Answer 4

Water + Carbon Dioxide → Glucose + Oxygen.

Question 5

Photosynthesis chemical equation?

Answer 5

H20+CO2

Question 6

Where does photosynthesis happen?

Answer 6

In the chloroplasts of plant cells (chlorophyll is needed).

Question 7

What is the role of stomates?

Answer 7

Holes on the bottoms of leaves that open to let in CO₂ and close to conserve water.

Question 8

What controls the opening and closing of stomates?

Answer 8

Guard cells.

Question 9

What process releases energy?

Answer 9

Cellular respiration.

Question 10

Cellular respiration word equation?

Answer 10

Glucose + Oxygen → Water + Carbon Dioxide + ATP.

Question 11

Cellular respiration chemical equation?

Answer 11

C₆H₁₂O₆ + O₂ → H₂O + CO₂ + ATP.

Question 12

Where does cellular respiration happen?

Answer 12

In the mitochondria of all cells.

Question 13

What is ATP?

Answer 13

A form of energy used by cells, made from chemical energy in glucose.

Question 14

What is an organism?

Answer 14

All systems working together to maintain life and homeostasis.

Question 15

What is the function of the digestive system?

Answer 15

To digest and absorb nutrients.

Question 16

What is the main function of the respiratory system?

Answer 16

Gas exchange (oxygen and carbon dioxide).

Question 17

What does the immune system do?

Answer 17

Protects the body from viruses, bacteria, and other pathogens/antigens.

Question 18

What are pathogens?

Answer 18

Disease-causing organisms like viruses, bacteria, fungi, and microorganisms.

Question 19

What are antigens?

Answer 19

Produce antibodies that fit antigens and destroy or label pathogens for destruction.

Question 20

How do vaccines work?

Answer 20

Inject dead or weakened pathogens so WBC can make antibodies and create immunity.

Question 21

What are antibiotics used for?

Answer 21

Fighting bacterial infections.

Question 22

What causes allergies?

Answer 22

The body making antibodies to harmless antigens like pollen or dust.

Question 23

How does AIDS affect the immune system?

Answer 23

HIV destroys WBCs, leading to no immunity.

Question 24

What is the main function of the nervous system?

Answer 24

Fast communication between cells to maintain homeostasis.

Question 25

What is a feedback mechanism?

Answer 25

Process that maintains homeostasis by regulating levels of sugar, water, or calcium.

Question 26

Give an example of a feedback mechanism.

Answer 26

If blood sugar is high, insulin is released from the pancreas to lower it.

Question 27

What does the excretory system do?

Answer 27

Removes wastes from the body (kidneys, skin, lungs).

Question 28

What is the skeletal/muscular system responsible for?

Answer 28

Locomotion (movement).

Question 29

What is dynamic equilibrium?

Answer 29

Constant small corrections to maintain homeostasis.

Question 30

What are enzymes?

Answer 30

Special proteins that digest or synthesize large molecules, acting as catalysts.

Question 31

How are enzymes specific?

Answer 31

Each enzyme fits only one substrate, like a lock and key.

Question 32

Give examples of enzyme actions.

Answer 32

• Protease digests proteins • Lactase digests lactose • Lipase digests lipids

Question 33

What do enzymes do to reactions?

Answer 33

Enzymes make reactions happen up to 1000 times faster.

Question 34

What happens if you change the shape of an enzyme (denature)?

Answer 34

You change its speed or stop it from functioning.

Question 35

What factors affect enzyme activity?

Answer 35

Temperature, pH (acidic/basic), and amount of enzyme or substrate.

Question 36

What is the optimal temperature or pH for an enzyme?

Answer 36

The specific temp or pH where the enzyme works the fastest (highest rate).

Question 37

What happens to enzyme activity if the temperature or pH is not optimal?

Answer 37

The enzyme activity slows down or stops.

Question 38

What happens when substrate concentration increases?

Answer 38

Reaction rate increases until saturation is reached, then it levels off.

Question 39

How do enzyme activity graphs look for temperature and pH?

Answer 39

They both show a peak at the optimum and then a sharp decline after.

Question 40

What does the graph of substrate concentration vs reaction rate show?

Answer 40

Reaction rate rises quickly then levels off when enzymes are saturated.