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海洋水西維吉尼亞州海洋

Bluegill on nest-1

Brook trout-3

Ash Meadows Amargosa pupfish-4

Redline darter -2

Brook trout-3

Brook trout-1

Chucky Madtom

Chinook salmon-3

Blue Patterned Fish

Porcupinefish fish

Shortfin Mako Shark - Isurus oxyrinchus

Dna Gene

School girl

孩子們學校

Lung

醫療藥物科學

Stingray Fish

Redbreast sunfish-6

Brook trout in Seneca Creek-1

Alewife-2

White-tipped reef sharks, Tern Island

Nerd

Medical Doctor

Grape Leaf

Teacher and Student Saying Bye Bye

Brightly lit Florida bluegill

Bluegill on nest-1

野生動物魚

Yellow bullhead catfish-4

Bluegill-3

野生動物魚

Redear sunfish-3

Close-up of Redbreast Sunfish

Chinook salmon-5

Brook trout-1

European Chub - Squalius cephalus

Brook trout-3

Brook trout-1

Brook trout-2

Brook trout-2

Bluegill on nest-1

Bonytail Chub

Zebra Head

Student Girl with Camera

Virus Germ

生物學病原體

Mimic shiner-1

Largemouth bass in vegetation

Sea turtle release after the cold weather.

Male bowfin hides in vegetation-4

Young brook trout with fall leaves in water-1

Mimic shiner-2

Mimic shiner-2

Redear sunfish school with other species of sunfish-1

Redbreast sunfish-1

Redline darter -3

Bluegill and Redear sunfish

Full Bath Bucket

Varicose and normal vein

醫療衛生醫學

Dinosaurus

Triceratops Dinosaur Skull

Male Student with Smartphone

Red Fringed Tulip in a Flowery Garden

天時熱自然

Green and Brown Mountain

(Tim) Medical Doctor Man

Science Teacher with Student

Cameron Indoor Stadium with student tents at Duke University, North Carolina

Stacked Books

Videographer interviews biologist-1

A Petri dish culture plate, which had contained a growth medium of sheep blood agar (SBA), and which was inoculated with Gram–positive, Burkholderia pseudomallei 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”.

Western Mosquitofish-1

Hospital Building

建築物醫學

(Martine) Nurse is Using a Pointer

Videographer interviews biologist

Student Girl

Student Girl

護理人員

(Kendra) Girl is Reading a Book

School girl

孩子們學校

Brook trout-1

Young brook trout with fall leaves in water-2

Redbreast sunfish-1

Young brook trout with fall leaves in water-1

Brook trout-1

Redbreast sunfish-1

Redbreast sunfish-2

Redbreast sunfish-3

A 3D graphical representation of a number of norovirus virions, set against a black background. 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”.

MERS Coronavirus Particles–Colorized scanning electron micrograph of MERS virus particles (yellow) both budding and attached to the surface of infected VERO E6 cells (blue). 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”.

顯微鏡藍色

Dinosaur Fossil

Mountain yellow-legged frog tadpole

兩棲動物水下

Bluegill on nest-1

Redear sunfish

Team surgeon at work on operating in hospital

Team surgeon at work on operating in hospital

Ash Meadows Amargosa pupfish-1

Bluegill on nest-1

Preparing to tag black bear cub

野生動物哺乳动物

A technician placing the repackaged influenza samples into a cold–storage environment within the laboratory setting. 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–This scanning electron microscope image shows SARS-CoV-2—also known as 2019-nCoV, 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”.

顯微鏡健康

Biologist monitors aquatic plants-2

Medical Doctor Nurse Patient

Biologist searches for freshwater mussels

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