Life Science (Grade 7) Midterm — Semester 1, Form B
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Free printable Life Science midterm (Grade 7): 15 multiple-choice questions plus 1 written response covering Cells, Genetics & Heredity, Evolution & Adaptation. Answer key included — customize it in the Midterm Maker.
Life Science (Grade 7) Midterm — Semester 1, Form B
Name: Date: Period:
Directions: Read each question carefully and choose the best answer. Answer the written response in complete sentences.
Covers: Cells · Genetics & Heredity · Evolution & Adaptation
Part 1: Multiple Choice
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What is the basic unit of structure and function in all living things?
- A. The cell
- B. The organ
- C. The atom
- D. The tissue
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What do prokaryotic cells, such as bacteria, lack?
- A. DNA
- B. A nucleus
- C. Ribosomes
- D. A cell membrane
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Which organelle contains the cell's DNA and controls its activities?
- A. Nucleus
- B. Vacuole
- C. Cell membrane
- D. Ribosome
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Which organelle releases energy from food through cellular respiration?
- A. Golgi apparatus
- B. Mitochondrion
- C. Chloroplast
- D. Nucleus
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Which organelles build proteins?
- A. Chloroplasts
- B. Vacuoles
- C. Ribosomes
- D. Lysosomes
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How many chromosomes are in a typical human body cell?
- A. 23
- B. 92
- C. 48
- D. 46
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What is the shape of a DNA molecule?
- A. Single straight strand
- B. Triple spiral
- C. Double helix
- D. Flat circle
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What are different forms of the same gene called?
- A. Chromosomes
- B. Proteins
- C. Phenotypes
- D. Alleles
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What is the term for an organism's observable traits, such as height or color?
- A. Genotype
- B. Allele
- C. Phenotype
- D. Gene
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Which scientist is known as the father of genetics for his work with pea plants?
- A. Charles Darwin
- B. Louis Pasteur
- C. Robert Hooke
- D. Gregor Mendel
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Why did dark peppered moths become more common near polluted English cities in the 1800s?
- A. Light moths moved to the countryside
- B. Pollution dyed the light moths dark
- C. They were harder for birds to see on soot-darkened trees
- D. Moths chose to change their color
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A human arm, a whale flipper, and a bat wing have similar bones but different uses. What are these called?
- A. Vestigial structures
- B. Analogous structures
- C. Homologous structures
- D. Learned behaviors
-
What is an adaptation?
- A. An inherited trait that helps an organism survive and reproduce
- B. A change an organism chooses to make
- C. A skill an animal learns from its parents
- D. A trait shared by every species on Earth
-
Why is variation within a population important?
- A. It stops natural selection from happening
- B. Some individuals may survive if the environment changes
- C. It makes every individual identical
- D. It guarantees every individual survives
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Which statement best describes natural selection?
- A. Individuals with helpful inherited traits tend to survive and reproduce more
- B. All individuals survive and reproduce equally
- C. Organisms change on purpose to fit their environment
- D. The largest individual always survives
Part 2: Written Response
- In guinea pigs, black fur (B) is dominant over white fur (b). Two Bb guinea pigs are crossed. Draw or describe the Punnett square and give the expected genotype and phenotype ratios.
Answer Key — Life Science (Grade 7) Midterm — Semester 1, Form B
- A — The cell Every living thing is made of one or more cells.
- B — A nucleus Prokaryotes have DNA but no membrane-bound nucleus.
- A — Nucleus The nucleus holds DNA, the instructions for the cell.
- B — Mitochondrion Mitochondria break down sugar to release usable energy.
- C — Ribosomes Ribosomes link amino acids together to make proteins.
- D — 46 Human body cells have 23 pairs, or 46 chromosomes.
- C — Double helix DNA is two strands twisted around each other.
- D — Alleles Alleles are versions of a gene, such as T or t.
- C — Phenotype Phenotype is what you can see; genotype is the allele combination.
- D — Gregor Mendel Mendel discovered patterns of inheritance by breeding pea plants.
- C — They were harder for birds to see on soot-darkened trees Camouflaged dark moths survived and reproduced more often.
- C — Homologous structures Similar bone structure suggests a common ancestor.
- A — An inherited trait that helps an organism survive and reproduce Adaptations are inherited and improve survival or reproduction.
- B — Some individuals may survive if the environment changes Different traits make it more likely that some individuals survive change.
- A — Individuals with helpful inherited traits tend to survive and reproduce more Helpful traits become more common over generations.
Written Response — Look-Fors
- Correct square (BB, Bb, Bb, bb); genotype ratio 1:2:1; phenotype ratio 3 black : 1 white (75% black, 25% white); uses dominant/recessive vocabulary.