Biology B1 Flashcards
(37 cards)
What is the main difference between prokaryotic and eukaryotic cells?
Prokaryotic cells (e.g., bacteria) have no nucleus; eukaryotic cells (e.g., plant and animal cells) do.
Name three organelles found in plant cells but not in animal cells.
Cell wall, chloroplasts, permanent vacuole
What is the function of the mitochondria?
Site of aerobic respiration, releasing energy.
What is the function of a root hair cell and how is it adapted?
Absorbs water and minerals; has a large surface area.
How is a sperm cell specialised?
Tail for movement, lots of mitochondria, enzymes to penetrate egg.
What’s the role of a nerve cell?
To carry electrical signals around the body.
What is diffusion?
Movement of particles from high to low concentration.
What is osmosis?
Movement of water across a partially permeable membrane from dilute to concentrated solution.
What is active transport?
Movement of substances against the concentration gradient, requiring energy.
What is a eukaryotic cell?
A cell with a nucleus and membrane-bound organelles (e.g., animal, plant cells).
What is a prokaryotic cell?
A simpler cell without a nucleus, e.g., bacterial cell.
Name all the organelles found in an animal cell.
Nucleus, cytoplasm, cell membrane, mitochondria, ribosomes.
Name the additional organelles in a plant cell.
Cell wall, chloroplasts, permanent vacuole.
What structures are found in bacterial cells?
Cell wall, cell membrane, cytoplasm, plasmids, single circular DNA strand.
What is the difference between light and electron microscopes?
Light microscopes have lower resolution; electron microscopes give higher magnification and detail.
Define magnification and resolution.
Magnification = how much bigger an image is than the object. Resolution = clarity/detail of the image.
How do you calculate magnification?
Image size ÷ real size.
Why do cells specialise?
To perform specific functions efficiently.
Name 3 specialised animal cells.
Sperm cell, nerve cell, muscle cell.
Name 3 specialised plant cells.
Root hair cell, xylem cell, phloem cell.
When do most animal cells differentiate?
Early in development.
When can plant cells differentiate?
Throughout their life.
What is a stem cell?
An undifferentiated cell that can become any type of cell.
