Life Science (Grade 7) Midterm — Units 1–2

Part 1: Multiple Choice

1. Which structure controls what enters and leaves the cell?
   1. A. Cell membrane
   2. B. Cell wall
   3. C. Nucleus
   4. D. Chloroplast
2. In which organelle does photosynthesis take place?
   1. A. Mitochondrion
   2. B. Chloroplast
   3. C. Lysosome
   4. D. Ribosome
3. Which structure is found in plant cells but not in animal cells?
   1. A. Ribosome
   2. B. Cell wall
   3. C. Cell membrane
   4. D. Mitochondrion
4. Which list shows levels of organization from smallest to largest?
   1. A. Cell, organ, tissue, organ system
   2. B. Organ, tissue, cell, organ system
   3. C. Tissue, cell, organ, organ system
   4. D. Cell, tissue, organ, organ system
5. Which statement is part of the cell theory?
   1. A. Cells can form from nonliving matter
   2. B. All cells contain chloroplasts
   3. C. All living things are made of one or more cells
   4. D. All organisms are made of many cells
6. What is the basic unit of structure and function in all living things?
   1. A. The cell
   2. B. The organ
   3. C. The atom
   4. D. The tissue
7. What do prokaryotic cells, such as bacteria, lack?
   1. A. DNA
   2. B. A nucleus
   3. C. Ribosomes
   4. D. A cell membrane
8. Which organelle contains the cell's DNA and controls its activities?
   1. A. Nucleus
   2. B. Vacuole
   3. C. Cell membrane
   4. D. Ribosome
9. Which organelle releases energy from food through cellular respiration?
   1. A. Golgi apparatus
   2. B. Mitochondrion
   3. C. Chloroplast
   4. D. Nucleus
10. Which organelles build proteins?
    1. A. Chloroplasts
    2. B. Vacuoles
    3. C. Ribosomes
    4. D. Lysosomes
11. Sex cells such as eggs and sperm are produced by which process?
    1. A. Fertilization
    2. B. Mitosis
    3. C. Binary fission
    4. D. Meiosis
12. An organism with the genotype Tt is described as what?
    1. A. Purebred
    2. B. Heterozygous
    3. C. Homozygous recessive
    4. D. Homozygous dominant
13. Which tool is used to predict the possible genotypes of offspring?
    1. A. Pedigree of fossils
    2. B. Dichotomous key
    3. C. Food web
    4. D. Punnett square
14. Two Tt pea plants are crossed. What percent of offspring are expected to be tt?
    1. A. 50%
    2. B. 25%
    3. C. 0%
    4. D. 75%
15. Tall (T) is dominant over short (t). What percent of offspring from Tt × tt are expected to be tall?
    1. A. 25%
    2. B. 75%
    3. C. 50%
    4. D. 100%
16. How many chromosomes are in a typical human body cell?
    1. A. 23
    2. B. 92
    3. C. 48
    4. D. 46
17. What is the shape of a DNA molecule?
    1. A. Single straight strand
    2. B. Triple spiral
    3. C. Double helix
    4. D. Flat circle
18. What are different forms of the same gene called?
    1. A. Chromosomes
    2. B. Proteins
    3. C. Phenotypes
    4. D. Alleles
19. What is the term for an organism's observable traits, such as height or color?
    1. A. Genotype
    2. B. Allele
    3. C. Phenotype
    4. D. Gene
20. Which scientist is known as the father of genetics for his work with pea plants?
    1. A. Charles Darwin
    2. B. Louis Pasteur
    3. C. Robert Hooke
    4. D. Gregor Mendel

Part 2: Written Response

21. 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.