Extra Test Practise Questions Flashcards
Explain the role of mitochondria in energy production. What is the connection between mitochondria and aerobic respiration?
The role of the mitochondria is for energy production through aerobic respiration, converting chemical energy from food into ATP.
How is photosynthesis and cellular respiration interconnected in the environment?
Photosynthesis makes glucose which is used in cellular respiration for making ATP. The glucose is then transformed back into carbon dioxide, which is used in photosynthesis.
What are lysosomes?
Lysosomes are a membrane bound organelle found in animal cells. They remove waste using digestive enzymes.
What are centrosomes?
Centrosomes are a membrane bound organelle found in animal cells. They are crucial for cell division.
What will happen to the movement of water in a plant cell exposed to a hypertonic solution?
Water will move out of the cell.
What will happen to the movement of water in a plant cell exposed to a hypotonic solution.
Water will move into the cell.
What is the role of the rough endoplasmic reticulum?
To synthesise and package proteins for transport within the cell.
What is the role of the golgi body?
Further modify and package proteins.
Why do muscles have more mitochondria than skin cells?
They need more energy for movement.
Describe osmosis:
Movement of water from low to high concentration through a semi permeable membrane.
How do cells in the small intestine adapt to absorb nutrients efficiently?
By a large surface area created by villi and microvilli along with a rich blood supply and specialised transport mechanisms.
Two adaptations allowing bacteria to thrive in extreme environments.
Enzyme adaptations - Bacteria can produce in extremely hot environments.
Specialised membrane lipids are modified in a way that makes the cell membrane able to withstand high temps.
Explain antibiotics:
They selectively target bacterial cells while leaving human cells unharmed. Bacteria have a cell wall however humans do not, therefore the antibiotics target the cell wall. They are also designed to effect the larger and differently structured ribosomes in humans.
How are antibiotics made?
Through a process called fermentation where bacterial strains are grown in controlled environments to produce antibiotics.
Endosymbiotic theory:
Eukaryotic cells came from prokaryotes engulfing other prokaryotes, leading to the formation of organelles like mitochondria and chloroplasts. Evidence can be seen through their double membrane and own circular DNA of the mitochondria and chloroplasts. And as they divide using binary fission independent to the cell.
By product of anaerobic respiration:
Lactic acid from fermentation due to ineffective pyruvate transport.
How does bacteria contribute to nutrient cycling in ecosystems?
By decomposing organic matter and fixing atmospheric nitrogen.
Two conditions that influence growth of bacteria?
Temperature and moist conditions.
As the cell grows explain what happens to their ability to exchange materials with the external environment.
It is harder for nutrients and waste to move efficiently across the membrane, as when cell size increases the surface area to volume ratio decreases, slowing diffusion.
Hypertonic:
A hypertonic solution has a higher solute concentration (and therefore lower water concentration) compared to a cell, causing water to move out of the cell and shrink.
Hypotonic:
A hypotonic solution has a lower solute concentration (and therefore higher water concentration) compared to a cell, causing the water to move into the cell and potentially swell or burst.
