What is the jelly-like substance inside a cell where chemical reactions happen?
Cytoplasm
What is a group of similar cells working together called?
A tissue
What is an element?
A substance made of only one type of atom
Give one property of nonmetals
They are dull, brittle, or poor conductors
What do we use to test if a substance is an acid or alkali?
Litmus paper or universal indicator
Name two structures that are found only in plant cells but not in animal cells.
Cell wall and chloroplasts
What is a group of different tissues working together called?
An organ
Give an example of a mixture.
Air, salad, salt water, potato salad, blueberry muffin, etc
Compare the appearance of metals and nonmetals.
Metals are shiny ; nonmetals are dull
What color does blue litmus turn in acid?
Red
A scientist looks at two cells under a microscope. One has chloroplasts and a cell wall, the other doesn’t.
Which type of cells are they?
Plant cell and animal cell, respectively.
Give an example of an organ system in the human body.
Examples: circulatory system, digestive system, respiratory system
Of the four boxes shown, which one represents a model of elements only?
C
Why are cooking pots made of metal but their handles made of plastic or wood?
Metals conduct heat; plastic and wood don’t.
Name two common household acids and two alkalis.
Acids: vinegar, lemon juice;
Alkalis: soap, baking soda, antiacid
How is a root hair cell adapted to absorb water?
It has a large surface area and a large vacuole
Arrange the following in the correct order from smallest to largest:
Tissue, Organ, Cell, Organ System
Cell → Tissue → Organ → Organ System
What is the difference between a compound and a mixture?
In compounds, elements are chemically bonded; in mixtures, they are not.
Give one example of an alloy made from two metals.
Brass
Steel
What does a universal indicator color of green tell you about a substance?
It is neutral (pH 7)
Why does a leaf cell contain many chloroplasts, while a root cell has none?
Leaf cells perform photosynthesis using sunlight; root cells are underground and don’t receive light.
A group of students listed these body parts: heart, blood, red blood cells, circulatory system.
Arrange them in order from smallest to largest level of organization.
Red blood cells → Blood → Heart → Circulatory system
Which one of the following diagrams represents a mixture, an element and a compound?
D
Name one alloy made by combining copper with another metal (used in sports awards).
Bronze
You test four unknown liquids with universal indicator and get pH values of 2, 7, 9, and 13.
Which are acids, neutral, and alkalis — and which one is the strongest alkali?
Acids: pH 2;
Neutral: pH 7;
Alkalis: pH 9 and 13;
Strongest alkali: pH 13.