Bionergetics ( part 1) Flashcards
What is the equation for photosynthesis ?
carbon dioxide + water –> glucose + oxygen
6CO2 + 6H2O –> C6 H12 O6 + 6O2
Balanced symbol equation
What two things are essential for photosynthesis
light ( energy) and chlorophyll
What is an endothermic reaction ?
Give an example
A reaction that takes in energy from the surroundings ie photosynthesis ( takes in light energy from the surroundings)
What is an exothermic reaction ?
Give an example
A reaction that releases energy into the surroundings
ie respiration
How is glucose used for storage in plants ?
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
How do plants use glucose for fruit ?
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
How do plants use glucose for protein synthesis ?
Glucose is combined with nitrate ions in the soil to make amino acids, which link to form proteins
How do plants use glucose for seeds ?
Glucose is turned into lipids ( fats) for storing in seeds
How do plants use glucose for cell walls ?
Glucose is converted into cellulose which is the substance used for making cell walls
What does a cell wall do ?
Provides plant cells with structural support and protection
Acts as a pressure vessel, preventing cell from over expanding when water enters by osmosis
what is the final use of glucose in plants and what is the use of it ?
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
What is the formula for aerobic respiration ?
glucose + oxygen –> carbon dioxide + water + energy
C6 H12 O6 + 6O2 → 6CO2 + 6H2O
How is the energy in respiration used by organisms ?
- protein synthesis
- muscle contraction
- nerve impulses
- mitosis
When energy is released in respiration what substance is it used to form ?
ATP - Adenosine Triphosphate
What is the mitochondria ?
Site of aerobic respiration
What do ribosomes do ?
Synthesise proteins ie enzymes
What is the cytoplasm ?
jelly like substance where chemical reactions occur including anaerobic respiration
What does the nucleus do ?
Contains the genetic information thereby controls what happens inside the cell
What does the cell membrane do ?
Acts as a gatekeeper, controls what enters and exits the cell
What is glycogen ?
A form of glucose that has been stored in the liver and muscles. It is made from many glucose molecules chained together.
What two substances join together to make fat ?
fatty acid and glycerol molecules
What is the difference between aerobic and anaerobic respiration ?
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
When does the body start using anaerobic respiration ?
When your muscle cells become short of oxygen because the blood cannot supply oxygen fast enough to your respiring cells
What is the equation for anaerobic respiration in animals ?
Glucose —> Lactic acid + energy
What is the equation for anaerobic respiration in plants ? aka fermentation
Glucose —> ethanol + carbon dioxide + energy
What can fermentation be used for ?
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
What does lactic acid build up do the muscles ?
Causes muscle cramps
What is oxygen debt ?
The amount of oxygen needed to break down lactic acid into carbon dioxide and water
What is the main role of muscle tissue ?
To contract in order to bring about movement
What is muscle tissue made of ?
protein fibres
What happens to your heart rate when you exercise and how does this help ?
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
What happens to your breathing rate during exercise and how does this help ?
Breathing rate increases
This increases volume of oxygen intake and also means that carbon dioxide can be exhaled quicker
What happens to your glycogen store during exercise and how does this help ?
Glycogen store decreases
More glucose is needed for respiration so more glycogen needs to be broken down to supply the glucose
What is metabolism ?
The sum of all the reactions that take place in a cell or in the body
What are some examples of metabolic reactions ?
- 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
How can stored glycogen provide glucose to respiring cells in different parts of the body ?
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
What are the three main functions of the liver ?
Storehouse, processing plant, manufacturing hub
How does the liver act as a storehouse ?
Stores nutrients the body doesn’t immediately need
How does the liver act as a processing plant ?
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
How does the blood from the body get to the liver ?
Hepatic portal vein - transports blood from the intestines to the liver
Hepatic artery - transports blood from heart to liver
How does the liver deal with toxins ( harmful substances)
Liver either isolates them and excretes them through the kidneys and intestines
Or converts them into harmless substances
What are some substances that the liver manufactures ?
- Vitamin D
- substances that help digestion
- blood plasma proteins
- cholesterol
- bile
What do hepatocyte cells do ?
Convert toxins into bile ( that’s how it’s made)
What are the main functions of bile ?
- breaks down fat
- destroys microbes
- neutralises stomach acid
What do blood plasma proteins do ?
Transport fatty acids and help form blood clots
