INTEGRATED SCIENCES$$ Flashcards
What is photosynthesis?
The process by which green plants, algae, and some bacteria convert light energy into chemical energy stored in glucose.
What is the key equation for photosynthesis?
6CO2 + 6H2O + light energy → C6H12O6 + 6O2
What are the reactants of photosynthesis?
- Carbon dioxide (CO2) * Water (H2O)
What are the products of photosynthesis?
- Glucose (C6H12O6) * Oxygen (O2)
Where does photosynthesis occur?
In the chloroplasts of plant cells.
What is respiration?
The process by which living organisms break down glucose to release energy.
What is the key equation for aerobic respiration?
C6H12O6 + 6O2 → 6CO2 + 6H2O + Energy (ATP)
What is the difference between aerobic and anaerobic respiration?
Aerobic respiration requires oxygen, while anaerobic respiration occurs in the absence of oxygen.
What are the reactants of aerobic respiration?
- Glucose (C6H12O6) * Oxygen (O2)
What are the products of anaerobic respiration in animals?
Lactic acid and energy.
What is the importance of respiration?
Releases energy for cellular functions such as growth, repair, and movement.
What is the link between photosynthesis and respiration?
The products of photosynthesis are the reactants for respiration, and vice versa.
What is chlorophyll?
The green pigment found in the chloroplasts of plants, algae, and cyanobacteria.
What role does chlorophyll play in photosynthesis?
Captures light energy from the sun.
What are the types of chlorophyll?
- Chlorophyll-a * Chlorophyll-b
How do plants use carbohydrates?
For immediate energy, storage, structural support, growth, transport, and defense.
What is gas exchange?
The process by which oxygen is absorbed into the blood and carbon dioxide is expelled.
What is the function of the trachea?
Carries air from the mouth/nose to the lungs.
What are alveoli?
Tiny, balloon-like air sacs at the ends of bronchioles where gas exchange occurs.
What is the function of the diaphragm during inhalation?
Contracts and flattens to increase chest volume.
What is ventilation?
The process of moving air in and out of the lungs.
What are the steps of inhalation?
- Diaphragm contracts * Intercostal muscles lift ribcage * Chest volume increases
What are the steps of exhalation?
- Diaphragm relaxes * Intercostal muscles lower ribcage * Chest volume decreases
What factors influence ventilation?
- Lung compliance * Airway resistance * Elastic recoil * Surface tension in alveoli
What gives maize its sweet taste?
Primarily from sugars, especially sucrose.
What are the key factors influencing sweetness in maize?
- Genetic varieties * Sugar-starch balance * Harvest timing * Enzymatic activity
Why does field corn taste less sweet?
It is bred for starch content, and sugars are rapidly converted to starch.
What is sweet corn?
Corn specifically bred to have higher sugar content compared to field corn.
At what stage is sweet corn harvested for peak sweetness?
At the milk stage.
What is the main pigment involved in photosynthesis?
Chlorophyll
What are the two main stages of photosynthesis?
Light-dependent reactions and Calvin Cycle
During respiration, glucose is broken down to produce?
ATP
Which of the following is the correct equation for photosynthesis?
6CO2 + 6H2O + Light → C6H12O6 + 6O2
Gas exchange occurs in which part of the lungs?
Alveoli
What is the primary role of the diaphragm in breathing?
Contracts to increase chest cavity volume
Which structure prevents the trachea from collapsing?
Cartilage rings
Which process occurs during exhalation?
Thoracic cavity volume decreases
What is the main carbohydrate responsible for the sweetness in sweet corn?
Sugar (sucrose, glucose, fructose)
Sweet corn retains its sweetness because?
It converts sugar to starch slowly
What is starch primarily used for in plants?
Long-term energy storage
What are the two main components of starch?
Amylose and Amylopectin
Where is cellulose found in plants?
Cell walls
Which statement about cellulose is TRUE?
It is composed of β-1,4 glycosidic bonds.
In human diets, cellulose is classified as?
An insoluble fiber
Why can some animals digest cellulose while humans cannot?
They produce the enzyme cellulase or rely on symbiotic microorganisms.
What is photosynthesis?
A process by which green plants convert light energy, carbon dioxide, and water into glucose and oxygen.
What is respiration?
A metabolic process in which cells break down glucose into energy (ATP), releasing carbon dioxide and water.
What is ventilation?
The physical process of moving air into and out of the lungs.
What is starch?
A complex carbohydrate made of glucose units, used by plants as a storage form of energy.
What is cellulose?
A structural carbohydrate found in the cell walls of plants.
What is gas exchange?
The process by which oxygen moves into the blood and carbon dioxide is expelled.
What are alveoli?
Tiny air sacs in the lungs where gas exchange occurs.
What is the role of the diaphragm?
Contracts during inhalation to increase chest volume.
What gives maize its sweet taste?
Sugar (sucrose, glucose, fructose)
Sweet corn is harvested at the __________ stage when sugar levels are at their peak.
Milk
Supersweet corn is sweeter than standard sweet corn because it contains a genetic mutation that __________.
Slows the conversion of sugar into starch
Starch is a __________ carbohydrate made of glucose molecules.
Complex
What are the two types of respiration?
Aerobic (uses oxygen) and anaerobic (does not use oxygen)
What is ventilation?
Ventilation is the process of moving air into and out of the lungs to allow gas exchange.
What are the two stages of ventilation?
Inhalation (breathing in) and exhalation (breathing out)
What is starch?
Starch is a complex carbohydrate made of glucose units and used by plants for long-term energy storage.
What are the two components of starch?
Amylose (linear structure) and amylopectin (branched structure)
What is cellulose?
Cellulose is a structural carbohydrate found in plant cell walls, providing strength and rigidity.
Why can’t humans digest cellulose?
Humans lack the enzyme cellulase needed to break the β-1,4 glycosidic bonds in cellulose.
Where does gas exchange occur in the lungs?
In the alveoli, where oxygen enters the blood and carbon dioxide is expelled.
Why is a large surface area important in alveoli?
It allows for efficient gas exchange between air and blood.
What is chlorophyll?
Chlorophyll is a green pigment in chloroplasts that absorbs light energy for photosynthesis.
Why is chlorophyll important?
It captures sunlight, which is essential for producing glucose during photosynthesis.
What gives maize its sweetness?
The sugars sucrose, glucose, and fructose in sweet corn.
Why is sweet corn sweeter than field corn?
Sweet corn converts sugar to starch more slowly due to genetic mutations.
What is a physical change?
A change in the form or appearance of a substance, but its chemical composition remains the same.
What are characteristics of physical changes?
- No new substance is formed
- Changes are usually reversible
- Only physical properties like shape, size, or state are affected
What are examples of physical changes?
- Melting of ice
- Boiling of water
- Cutting paper
- Dissolving salt in water
What is a chemical change?
A chemical change leads to the formation of a new substance with different properties.
What are characteristics of chemical changes?
- A new substance is formed
- Changes are usually irreversible
- Heat, light, or gas may be released
What are examples of chemical changes?
- Burning of wood
- Rusting of iron
- Digestion of food
- Souring of milk
What is the rate of reaction?
The rate of reaction refers to how quickly a reactant is used up or a product is formed in a chemical reaction.
What is the effect of a catalyst on the rate of reaction?
A catalyst is a substance that speeds up a chemical reaction without being consumed in the process.
How does a catalyst work?
- Lowers the activation energy required for the reaction to proceed
- Provides an alternative pathway for the reaction
Give an example of a catalyst.
Enzymes act as biological catalysts in the human body.
What is the effect of surface area on the rate of reaction?
The larger the surface area of a solid reactant, the faster the reaction occurs.
How does increasing the concentration affect the rate of reaction?
Increasing the concentration of a reactant in a solution increases the rate of reaction.
What happens to the activation energy when a catalyst is added?
A catalyst lowers the activation energy, making it easier for the reactants to form products.
What is meant by ‘activation energy’?
The minimum energy needed for a reaction to occur.
What are the types of asexual reproduction in plants?
- Vegetative propagation
- Cuttings
- Grafting
- Spores
What is pollination?
The transfer of pollen (male gamete) from the anther to the stigma.
What is fertilization in plants?
The pollen reaches the ovary, where it fuses with the ovule (female gamete) to form a zygote.
What is seed dispersal?
Seeds spread away from the parent plant by wind, animals, water, or explosion.
What is germination?
The seed starts growing into a new plant under the right conditions (water, oxygen, warmth).
How does asexual reproduction differ from sexual reproduction in plants?
- Asexual: 1 parent, clones, faster
- Sexual: 2 parents (male & female), genetic diversity, slower
