Biology Word Search — Hard

Play a free online Biology word search puzzle. Difficulty: Hard. Find all 12 hidden words on the 12×12 grid below.

Words to find

Plus 4 hidden bonus words.

Biology word list, defined

HEMOGLOBIN /hɛməˈɡloʊbɪn/ · noun
A protein in red blood cells that carries oxygen from the lungs to the body's tissues and returns carbon dioxide from the tissues to the lungs. Related: globin, oxyhemoglobin, deoxyhemoglobin, methemoglobin.
ENDANGERED /ɪnˈdeɪn.dʒəd/ · adjective
At risk of harm, destruction, or extinction; especially used of plant and animal species threatened with dying out entirely. Related: threatened, at risk, imperiled, in jeopardy.
CHOLESTEROL /kəˈlɛstərɒl/ · noun
A waxy, fat-like substance (a sterol) found in the cells and bloodstream of animals, essential for building cell membranes and producing hormones and vitamin D; high levels of certain forms in the blood are associated with an increased risk of heart disease. Related: lipid, sterol, fat.
ADAPTATION /ˌædæpˈteɪʃən/ · noun
The process or state of adjusting to new conditions, whether by an organism evolving to suit its environment or by a person or thing being modified to fit a new purpose. It also refers to a work, such as a film, that has been adapted from another medium. Related: adjustment, modification, conversion, transformation.
GESTATION /ˈdʒɛstəʊʃən/ · noun
The period of development of a fetus inside the womb, from conception to birth. The process of growth or development of something. Related: pregnancy, development, incubation, maturation.
PATHOGEN /ˈpæθɒdʒən/ · noun
A disease-causing agent, such as a bacterium, virus, or fungus. A pathogen can cause a wide range of diseases in humans, animals, and plants. Related: disease agent, infectious agent, germ, microbe.
PLANKTON /plæŋktɒn/ · noun
Small, usually microscopic, plants or animals that live in water, especially in the sea. Plankton are an important food source for many larger animals. Related: microorganisms, phytoplankton, zooplankton, algae.
HIERARCHY /ˈhaɪərəki/ · noun
A system of organizing people or things in a series of levels, with each level having a higher or lower status or authority. A series of levels or ranks in a system or organization. Related: structure, organization, system, ladder.

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