43,827 免費圖片適用於學生

生物學水下魚海上生活野生動物動物水內華達州教育男生

Highland shiner

Logperch-2

Fantail darter

Ash Meadows Amargosa pupfish-1

Spotted sunfish

Ash Meadows Amargosa pupfish-1

school boy

孩子們學校

School boy

孩子們學校

School boy

孩子們學校

school boy

孩子們學校

School boy

孩子們學校

school boy

孩子們學校

School boy

孩子們學校

Medical Doctor Man

school

孩子們學校

A 440X photomicrograph magnification of a hematoxylin and eosin (H&E)–stained liver tissue specimen, revealed the presence of cytoarchitectural changes indicative of fatty degeneration. 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”.

電子學细菌

A 100X photomicrograph magnification of photomicrograph of a hematoxylin and eosin (H&E) stained liver tissue specimen, revealed the presence of histopathologic changes indicative of fatty degeneration. 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”.

Novel Coronavirus SARS-CoV-2–Colorized scanning electron micrograph of an apoptotic cell (blue) infected with SARS-COV-2 virus particles (red), isolated from a patient sample. 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”.

Frog Green

Student Girl

Medical Doctor with a Yellow Card

Pills

醫療藥物藥品

Aquarium fish

Aquarium fish

Lake chubsucker-1

Transparent Fish Background

Brook Trout juvenile-2

野生動物魚

Yellow bullhead catfish-1

Greenbrier Cave Crayfish

生物學樣本

Ash Meadows Amargosa pupfish-1

Devils Hole pupfish-1

Brown trout pair

Largemouth bass-1

Captive Devils Hole pupfish-3

Black Crappie - Pomoxis nigromaculatus

野生動物魚

Chinese Pattern

中國人中國

Chinese Pattern

中國人中國

Captive Devils Hole pupfish-3

Ash Meadows Amargosa pupfish-3

Ash Meadows Amargosa pupfish-1

Ash Meadows Amargosa pupfish-1

Black Fish Aquarium

Fetus

Woman is Bathing

Pallid Sturgeon-1

Bluegill searches for food

Brook Trout juvenile-2

野生動物魚

Western Mosquitofish

Captive Devils Hole pupfish

Ash Meadows Amargosa pupfish-1

Close-up of bluegill with other fish

Juvenile Spotted sunfish in clear water

Black Finger Crab - Ozius truncatus

Teacher and formulas

school boy

孩子們學校

Mandrill

哺乳动物動物

Male Student

School boy

孩子們學校

MERS Coronavirus Particles–Colorized scanning electron micrograph of Middle East Respiratory Syndrome virus particles attached to the surface of an infected VERO E6 cell. 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”.

香港多個民間團體、學者及大專學生在記者會上宣布「社區公民約章運動」詳情

Student Girl Cries in Depression

卡哇伊聖情人節恐龍紙杯蛋糕

情人節恐龍

Beetle

野生動物動物

Bath Bucket

Native american liaison and biologists with sedated black bear

野生動物科學

Tyrannosaurus Dinosaur Bone

骨組織恐龍

Male Student is Writing in His Notebook

Brittle Star on Sponge

Candy darter-1

Dolly Varden-1

Juvenile Rainbow trout-1

Candy darter

Dolly Varden-1

Juvenile Rainbow trout-2

Juvenile Rainbow trout-1

Candy darter-1

Juvenile Chinook salmon-2

Medical doctor nurse patient

Juvenile Chinook salmon-2

Preparing to tag black bear cub-3

哺乳动物生物學家

Biologists search for Fountain Darter-2

Juvenile Chinook salmon-2

Hybognathus placitus

Biologists search for Fountain Darter-1

Novel Coronavirus SARS-CoV-2–This scanning electron microscope image shows SARS-CoV-2 (round magenta 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”.

Lab technician adding a solution to an Enzyme–Linked Immunosorbent Assay (ELISA) plate 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”.

Woman Taking a Bath

Female Student Umbrella

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”.

Biologists search for Fountain Darter-1

Brook trout-1

A medical illustration of Clostridioides difficile bacteria, formerly known as Clostridium difficile. 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 100X photomicrograph magnification of a malachite green spore stained sample, revealed the presence of numerous Bacillus sp. bacteria. 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”.

生物學细菌

Bright Flower Free Photo

Young woman withdrawing money from credit card at ATM

Laboratory experiment

Microscope - Grayscale

實驗室科學

Maldive anemonefish - Amphiprion nigripes

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