Skeletons and Muscles
What is the main job of the skeleton?
Protects organs / helps movement
What does “unicellular” mean?
One-celled organism
What is a pathogen?
A microorganism that causes disease
What does a producer do in a food chain?
Makes its own food (usually by photosynthesis)
What is an adaptation?
A feature that helps an organism survive
A joint that allows bending, like the elbow.
Hinge joint
Name one type of unicellular organism.
Bacterium / yeast / protoctist
What do vaccines do?
Helps body make antibodies / immunity
What is a food web?
A network of connected food chains
Give one example of a desert adaptation.
Large ears to lose heat (jack rabbit)
What happens to a muscle when it contracts?
It becomes shorter and fatter
What is the word equation for fermentation in yeast?
Glucose → alcohol + carbon dioxide
How do white blood cells fight infection?
Engulf microbes or make antibodies
Name one reason why energy is lost at each level.
Energy lost as heat, movement, or waste
What is biodiversity?
Variety of living things in an area
How do two muscles work together to move a bone?
One contracts, one relaxes
Why don’t bacteria have a nucleus?
Because they are prokaryotes
Why don’t antibiotics work on viruses?
Viruses are not alive and use host cells
What does a pyramid of numbers show?
Number of organisms at each level
What is continuous variation?
Variation that shows a range (e.g. height)
Explain how antagonistic muscles move the arm during a bicep curl.
Biceps contract to pull; triceps relax. Opposite when straightening.
How does yeast respire differently when oxygen is and isn’t present?
With oxygen: aerobic respiration; without: fermentation
Describe how a vaccine leads to long-term immunity.
Vaccine triggers memory cells to respond faster next time
Explain what might happen if a top predator is removed from a food web.
Prey populations rise, imbalance occurs in food web
Explain how variation helps a species survive environmental change.
Some individuals survive better and pass on traits