Biology Crossword Puzzles: Free Printable and Online

Unravel the complexities of life itself, from microscopic cells to sprawling ecosystems. Explore genetics, evolution, and the wonders of the natural world.

Print any biology crossword below, download it as a PDF, or play it online. Free, and no signup is needed to play.

10 puzzles, click Print on any puzzle below

genus

Easy · 5×5 · 5 words
Play online →
1
2
3
4

Across

  1. 1. The genus Canis includes this common household pet.
  2. 2. A crustacean often found in the genus Cancer.
  3. 4. A non-flowering vascular plant in the genus Pteridium.

Down

  1. 1. A water bird belonging to the genus Anas.
  2. 3. A large primate classified within the genus Pongo or Pan.

Print pack

Print a set, not just a sheet

Two or four versions of this puzzle with different layouts, a separate answer key for each, your own header line, and no Grid Genius footer.

Your first worksheet, answer key, and play link stay free. The pack is the extra.

Biological

Easy · 5×5 · 5 words
Play online →
1
2
3
4
5

Across

  1. 1. The molecule that carries genetic instructions for life.
  2. 4. The organ that serves as the center of the nervous system.
  3. 5. The reproductive unit of a flowering plant.

Down

  1. 2. A fiber that transmits impulses to the brain.
  2. 3. An organ used for breathing air.

arachnid

Hard · 15×15 · 23 words
Play online →
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23

Across

  1. 4. Hardened dorsal shield covering the cephalothorax
  2. 5. Shedding one's hardened overcoat to permit expansion
  3. 7. Nursery parcel guarded in a spherical sac
  4. 8. Distal leg tip equipped with microscopic climbing claws
  5. 10. Polysaccharide armor forming the lightweight skeleton
  6. 14. Arachnid jaw mechanism designed to crush or pierce
  7. 16. Tail extremity that packs a toxic punch
  8. 18. Camouflaged subterranean door lined with soil and thread
  9. 19. Octet of ocular beads watching for vibration
  10. 20. Parasitic clockwork crawler spreading Lyme
  11. 21. Hourglass wearer with a reputation for lethal widowhood
  12. 22. Geometric suspended snare engineered of protein
  13. 23. Pertaining to the tail end that carries a sting

Down

  1. 1. Father figure absent after a cannibalistic mating encounter
  2. 2. The metamorphic act of crawling out of one's skin
  3. 3. Glands located near the leg base for liquid waste
  4. 6. Sydney resident lurking in ground silk tubes with deadly bite
  5. 9. Abdominal organ that prints liquid threads into open air
  6. 11. Daddylonglegs with no venom nor separate waistline
  7. 12. Glows neon under ultraviolet illumination with claws aloft
  8. 13. Scytodes missile that glues prey from a distance
  9. 15. Hollow syringe used before the digest begins
  10. 17. Silken tote bag carried under the sternum

biology

Easy · 7×7 · 6 words
Play online →
1
2
3
4
5
6

Across

  1. 2. Living organism that typically produces its own food via photosynthesis
  2. 5. Organ that filters waste from the blood
  3. 6. The command center of the nervous system

Down

  1. 1. Protein that speeds up chemical reactions in the body
  2. 3. Organ used for breathing
  3. 4. Large organ that cleans the blood and produces bile

Biology

Easy · 7×7 · 8 words
Play online →
1
2
3
4
5
6
7

Across

  1. 4. A hard part of the skeleton
  2. 5. The organ where food is digested
  3. 6. The organ used for seeing
  4. 7. The molecule that carries genetic information

Down

  1. 1. The underground part of a plant
  2. 2. A tiny living thing that can cause disease
  3. 3. A group of living things that are similar
  4. 5. The part of a flowering plant that can grow into a new one

Biology

Easy · 7×7 · 8 words
Play online →
1
2
3
4
5
6
7

Across

  1. 1. The small part of a plant that can grow into a new one
  2. 4. An organ used for breathing air
  3. 6. The organ used for seeing
  4. 7. A fiber that sends signals to the brain

Down

  1. 1. The outer layer of the body
  2. 2. The molecule that carries genetic information
  3. 3. The basic unit of all living things
  4. 5. A segment of DNA that determines a trait

Simple biology cells knowledge

Easy · 7×7 · 7 words
Play online →
1
2
3
4
5
6
7

Across

  1. 1. Any tiny part of a cell with a specific job
  2. 5. The scientific name for the cell control center
  3. 7. A small segment of DNA that determines a trait

Down

  1. 2. The simple sugar that cells use for fuel
  2. 3. The genetic material that carries instructions for life
  3. 4. A long cell that sends signals to the brain
  4. 6. Cells that form a protective layer over the body

Biology

Easy · 7×7 · 9 words
Play online →
1
2
3
4
5
6
7
8

Across

  1. 1. The small part of a plant that can grow into a new one
  2. 4. An organ used for breathing air
  3. 7. The organ used for seeing
  4. 8. The main trunk of a plant that supports leaves

Down

  1. 1. The outer layer covering a human body
  2. 2. An oval object from which a baby animal hatches
  3. 3. The basic building block of all living things
  4. 5. A tiny living thing that can cause disease
  5. 6. The part of a plant where photosynthesis usually happens

Life Cycles

Medium · 15×15 · 14 words
Play online →
1
2
3
4
5
6
7
8
9
10
11
12
13
14

Across

  1. 1. Earliest stage of a developing plant or animal, before birth or hatching
  2. 5. Young animal that has not yet reached adulthood
  3. 10. Immature, wingless feeding stage between egg and pupa in many insects
  4. 12. Process of a seed beginning to sprout and grow into a plant
  5. 13. Young insect that looks like a small adult and lacks a pupal stage
  6. 14. Total length of time an organism is expected to live

Down

  1. 2. Young produced by an animal or plant
  2. 3. Final, sexually mature stage of an organism's life cycle
  3. 4. Non-feeding stage during which an insect's body is completely rebuilt into its adult form
  4. 6. Describes a life cycle with only three main stages
  5. 7. Transfer of pollen that allows a flowering plant to produce seeds
  6. 8. Describes metamorphosis with four distinct stages, including a pupa
  7. 9. All the offspring born and living around the same time
  8. 11. To produce offspring of the same species

Life Cycles

Easy · 11×11 · 12 words
Play online →
1
2
3
4
5
6
7
8
9
10
11
12

Across

  1. 2. Resting stage between larva and adult in many insects
  2. 5. To break out of an egg
  3. 6. Adult amphibian that hops and can live on land or water
  4. 8. Hard protective case a caterpillar forms before becoming a butterfly
  5. 10. Fully grown stage of an animal's life cycle
  6. 12. Colorful part of a plant that helps it make seeds

Down

  1. 1. Flying insect with colorful wings that starts life as a caterpillar
  2. 3. Part of a plant that grows from a flower and holds seeds
  3. 4. Round object where many animals begin life
  4. 7. Young frog that lives in water and breathes with gills
  5. 9. Worm-like young stage of an insect after it hatches
  6. 11. Small part that a new plant can sprout from
Get AI Hints in the AppGet it on Google PlayPlay Biology Online

Make your own Biology crossword

Turn your own word list into a crossword with the free Grid Genius maker. Print it with an answer key or share a playable link with your class. No account needed.

Make your own Biology crossword

Related Printable Crossword Topics

Cell BiologyLife CyclesPhotosynthesisAnatomyAstronomyChemistryEcologyFamous InventionsFood ChainsGenetics & DNAHuman BodyMedicine

Biology Crossword FAQ

Is this Biology crossword puzzle free?

Yes. Every Biology crossword on this page is free. You can print it, download it as a PDF, or play it online without paying anything or creating an account.

Can I print the Biology crossword?

Yes. Click Print on any puzzle for a print-ready page with the grid, the clues, and a name and date line, or use Download to save it as a PDF, PNG, or JPEG for photocopying. The PDF download includes a filled answer key on the last page for grading.

Can students play these crosswords online?

Yes. Every puzzle has a Play online link that opens in the browser on any device. No app install and no signup is needed to play, which makes it easy to share with a class.

Can I make my own Biology crossword?

Yes. The free Grid Genius crossword maker builds a puzzle from your own words and clues, with a printable grid and answer key. The Grid Genius app can also generate a complete crossword from any topic you type.

Play Biology online|All printable topics|Browse all topics