42,647 免费图片适用于学生

生物学水下鱼动物海上生活野生动物水海洋性质女性

Aroma Soap

卫生学肥皂

Aroma Soap

卫生学肥皂

Female student attention

Student Boy Thinks of Money

Drug Blister

Plesiosaur

爬行动物恐龙

Greenery green space skyscraper

卫生学梳篦

Tyrannosaurus Dinosaur

古生物学恐龙

Aroma Soap

卫生学肥皂

Student desk

Satellite View of Earth

River carpsucker-1

Black Bullhead catfish-2

野生动物鱼

River and Rockhills

Student Girl

Praying Mantis

Pea Aphid

生物学性质

Student Boy Eats a Rice Ball

卫生学梳篦

A boy and a snowman playing hockey

Yellow bullhead catfish-3

Channel catfish-2

Quilback carpsucker-3

Rock Bass

Rainbow trout-1

Pallid Sturgeon-13

Paddlefish-2

Happy Medical Doctor

A photomicrograph of a direct fluorescent antibody (DFA)–stained specimen, revealing the presence of numerous Francisella tularensis coccobacilli. Original image sourced from US Government department: Public Health Image Library, Centers for Disease Control and Prevention. Under US law this image is copyright free, please credit the government department whenever you can”.

电子学细菌

Safety Razor

Rescue Wing Conducts

铁路列车人

Female Student is Reading a Book

Ash Meadows Speckled Dace-4

野生动物鱼

Purple crab

Front Cichlid Cyphotilapia Frontosa

Medical Doctor

Brook Trout juvenile-2

Devils Hole pupfish-5

野生动物鱼

Tidepool Sculpin

Ash Meadows Speckled Dace-2

Dinosaur Skeleton

College Student

古老的恐龙

Medical Doctor Man

Teacher is Teaching a Lesson to Students

孩子们学校

Medical Doctor Woman with X Sign

Business Woman is Writing

Books

Little flowers

競賽游泳古老的

心脏膈面健康

大學生

American hog-nosed skunk

哺乳动物动物

Freshwater drum

Brownish Fish

Sturgeon

Pallid sturgeon-4

Seamless Chinese Pattern

Couple of Students

Flounder Face

Copper Tetra

Smallmouth bass

野生动物鱼

Teacher

Pigeon

Puzzled Medical Doctor

Woman doing chores in bathroom, cleaning of water tap

工具类厨房

Anatomy of humane body

医疗药物插画

Brontosaurus

Ammonoidea Fossil

恐龙骨骼古生物学

scientist doing research in a quantum optics lab

Female student thinking smartphone

Female student sports day

Female student

Cyprinella callistia

Novel Coronavirus SARS-CoV-2–Transmission electron micrograph of SARS-CoV-2 virus particles, isolated from a patient. Original image sourced from US Government department: The National Institute of Allergy and Infectious Diseases. Under US law this image is copyright free, please credit the government department whenever you can”.

Test Tubes

版面模子科学

Female student

滑板运动学生

Biologists search for Fountain Darter

生物学家水

Luxilus chrysocephalus isolepis-6

Diamondback terrapin

爬行动物动物

Biologists search for Fountain Darter-2

生物学家水

Biologists search for Fountain Darter-2

生物学家水

Influenza virus experimentation with eggs. Original image sourced from US Government department: Public Health Image Library, Centers for Disease Control and Prevention. Under US law this image is copyright free, please credit the government department whenever you can”.

A scientist using a whole genome DNA sequencer, in order to determine the “DNA fingerprint” of a specific bacterium. Original image sourced from US Government department: Public Health Image Library, Centers for Disease Control and Prevention. Under US law this image is copyright free, please credit the government department whenever you can”.

生物学控制

Students in Kagera,Tanzania

Blue Tech Background

Students at Maclay School in Tallahassee, Florida

Student recreation center

建筑物城市

A photomicrograph reveals numerous Gram–negative, Francisella tularensis coccobacilli, the bacterium responsible for causing the disease, tularemia. Original image sourced from US Government department: Public Health Image Library, Centers for Disease Control and Prevention. Under US law this image is copyright free, please credit the government department whenever you can”.

电子学细菌

Woman girl smartphone student

Rainbow trout in stream

Biologists search for Fountain Darter-2

生物学家水

Biologists search for Fountain Darter-1

生物学家水

Panama City crayfish-2

生物学水下

Female Student with English Textbook

Teacher

Novel Coronavirus SARS-CoV-2–This scanning electron microscope image shows SARS-CoV-2 (round gold objects) emerging from the surface of cells cultured in the lab. SARS-CoV-2, also known as 2019-nCoV, is the virus that causes COVID-19. Original image sourced from US Government department: The National Institute of Allergy and Infectious Diseases. Under US law this image is copyright free, please credit the government department whenever you can”.

Student Boy with Camera

照相機学生

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