Bionergetics ( part 1)

Question 1

What is the equation for photosynthesis ?

Answer 1

carbon dioxide + water –> glucose + oxygen

6CO2 + 6H2O –> C6 H12 O6 + 6O2
Balanced symbol equation

Question 2

What two things are essential for photosynthesis

Answer 2

light ( energy) and chlorophyll

Question 3

What is an endothermic reaction ?

Give an example

Answer 3

A reaction that takes in energy from the surroundings
ie photosynthesis ( takes in light energy from the surroundings)

Question 4

What is an exothermic reaction ?

Give an example

Answer 4

A reaction that releases energy into the surroundings

ie respiration

Question 5

How is glucose used for storage in plants ?

Answer 5

Glucose is converted into insoluble starch for storage

Starch can be stored in roots, leaves and stems to provide plant with food when photosynthesis isn’t happening ie at night

Question 6

How do plants use glucose for fruit ?

Answer 6

Glucose, and another sugar- fructose are turned into sucrose for storing in fruits

Fruits deliberately taste nice so animals will eat them and disperse the seeds in their faeces

Question 7

How do plants use glucose for protein synthesis ?

Answer 7

Glucose is combined with nitrate ions in the soil to make amino acids, which link to form proteins

Question 8

How do plants use glucose for seeds ?

Answer 8

Glucose is turned into lipids ( fats) for storing in seeds

Question 9

How do plants use glucose for cell walls ?

Answer 9

Glucose is converted into cellulose which is the substance used for making cell walls

Question 10

What does a cell wall do ?

Answer 10

Provides plant cells with structural support and protection

Acts as a pressure vessel, preventing cell from over expanding when water enters by osmosis

Question 11

what is the final use of glucose in plants and what is the use of it ?

Answer 11

Plants use some of the glucose they produce for respiration

Respiration releases energy, allows plant to convert the rest of the glucose into other useful substances ie proteins, lipids

Question 12

What is the formula for aerobic respiration ?

Answer 12

glucose + oxygen –> carbon dioxide + water + energy

C6 H12 O6 + 6O2 → 6CO2 + 6H2O

Question 13

How is the energy in respiration used by organisms ?

Answer 13

• protein synthesis
• muscle contraction
• nerve impulses
• mitosis

Question 14

When energy is released in respiration what substance is it used to form ?

Answer 14

ATP - Adenosine Triphosphate

Question 15

What is the mitochondria ?

Answer 15

Site of aerobic respiration

Question 16

What do ribosomes do ?

Answer 16

Synthesise proteins ie enzymes

Question 17

What is the cytoplasm ?

Answer 17

jelly like substance where chemical reactions occur including anaerobic respiration

Question 18

What does the nucleus do ?

Answer 18

Contains the genetic information thereby controls what happens inside the cell

Question 19

What does the cell membrane do ?

Answer 19

Acts as a gatekeeper, controls what enters and exits the cell

Question 20

What is glycogen ?

Answer 20

A form of glucose that has been stored in the liver and muscles. It is made from many glucose molecules chained together.

Question 21

What two substances join together to make fat ?

Answer 21

fatty acid and glycerol molecules

Question 22

What is the difference between aerobic and anaerobic respiration ?

Answer 22

Aerobic respiration uses oxygen, anaerobic respiration doesn’t

Aerobic respiration takes place in the mitochondria while anaerobic respiration takes place in the cytoplasm

Aerobic respiration is more efficient

Question 23

When does the body start using anaerobic respiration ?

Answer 23

When your muscle cells become short of oxygen because the blood cannot supply oxygen fast enough to your respiring cells

Question 24

What is the equation for anaerobic respiration in animals ?

Answer 24

Glucose —> Lactic acid + energy

Question 25

What is the equation for anaerobic respiration in plants ? aka fermentation

Answer 25

Glucose —> ethanol + carbon dioxide + energy

Question 26

What can fermentation be used for ?

Answer 26

Ethanol can be used for brewing alcoholic drinks ie beer and wine

Carbon dioxide can be used in the baking industry to help make dough rise

Question 27

What does lactic acid build up do the muscles ?

Answer 27

Causes muscle cramps

Question 28

What is oxygen debt ?

Answer 28

The amount of oxygen needed to break down lactic acid into carbon dioxide and water

Question 29

What is the main role of muscle tissue ?

Answer 29

To contract in order to bring about movement

Question 30

What is muscle tissue made of ?

Answer 30

protein fibres

Question 31

What happens to your heart rate when you exercise and how does this help ?

Answer 31

Heart rate increases

This increases blood flow which means that oxygen can be supplied faster to respiring muscle cells and waste substances can be removed faster

Question 32

What happens to your breathing rate during exercise and how does this help ?

Answer 32

Breathing rate increases

This increases volume of oxygen intake and also means that carbon dioxide can be exhaled quicker

Question 33

What happens to your glycogen store during exercise and how does this help ?

Answer 33

Glycogen store decreases

More glucose is needed for respiration so more glycogen needs to be broken down to supply the glucose

Question 34

What is metabolism ?

Answer 34

The sum of all the reactions that take place in a cell or in the body

Question 35

What are some examples of metabolic reactions ?

Answer 35

• Conversion of glucose to starch, glycogen and cellulose
• use of glucose and nitrate ions to form amino acids
• respiration
• photosynthesis
• the formation of lipid molecules
• breakdown of excess proteins in the liver to form urea

Question 36

How can stored glycogen provide glucose to respiring cells in different parts of the body ?

Answer 36

Firstly, it is broken down into glucose molecules by the liver.

The glucose then diffuses into the bloodstream where it is transported via the blood stream to respiring tissues in different parts of the body

The glucose will then diffuse into the cells to be used in respiration

Question 37

What are the three main functions of the liver ?

Answer 37

Storehouse, processing plant, manufacturing hub

Question 38

How does the liver act as a storehouse ?

Answer 38

Stores nutrients the body doesn’t immediately need

Question 39

How does the liver act as a processing plant ?

Answer 39

One of the liver’s main roles is to filter the body’s blood
It does this with the help of lobules which are tiny processing plants that help sort, process and store the nutrients from blood

Question 40

How does the blood from the body get to the liver ?

Answer 40

Hepatic portal vein - transports blood from the intestines to the liver

Hepatic artery - transports blood from heart to liver

Question 41

How does the liver deal with toxins ( harmful substances)

Answer 41

Liver either isolates them and excretes them through the kidneys and intestines

Or converts them into harmless substances

Question 42

What are some substances that the liver manufactures ?

Answer 42

• Vitamin D
• substances that help digestion
• blood plasma proteins
• cholesterol
• bile

Question 43

What do hepatocyte cells do ?

Answer 43

Convert toxins into bile ( that’s how it’s made)

Question 44

What are the main functions of bile ?

Answer 44

• breaks down fat
• destroys microbes
• neutralises stomach acid

Question 45

What do blood plasma proteins do ?

Answer 45

Transport fatty acids and help form blood clots