42,648 免费图片适用于学生

生物学动物水下海上生活鱼海洋水洋海野生动物

Stop Coronavirus

Teacher at the Blackboard

急救包

Medical Doctor Woman is Using a Tablet

Green sea Turtle

Young brook trout with fall leaves in water

White grey shark jaws close up portrait

Plant Growth

Woman is Bathing

colorful leaf texture

colorful leaf texture

Medicine

Brook trout-3

water drops on the leaf

California halibut - Paralichthys californicus

Red Tailed Catfish swimming in water -- Phractocephalus hemioliopterus

Alewife-2

Angel Fish Tank

Yellow bullhead catfish-4

Brook trout-1

大食蚁兽

野生动物动物

A medical illustration of drug–resistant, Neisseria gonorrhoeae 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”.

Bouquet

(Joshua) Medical Doctor

洗发精

卫生学肥皂

洗发精

卫生学肥皂

洗发精

卫生学肥皂

Doctor Mask Hospital

Hospital Face Mask 3

Hospital Face Mask 5

Gila trout-4

A 1000X photomicrograph magnification of numerous, rod-shaped, Gram–negative, Yersinia pestis bacilli. 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 1125X photomicrograph magnification of Giemsa stained blood smear, revealed a number of Plasmodium falciparum parasites, in the form of gametocytes, and ring-form trophozoites. 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”.

生物学细菌

Yellow Soap

Test Tubes from experimenting on coronavirus. 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”.

医疗药物细菌

Hospital Face Mask

Juvenile Chinook salmon-1

Pills Medicine

医疗药物健康

Pills Medicine

医疗药物健康

A 1125X photomicrograph magnification of a Giemsa stained, thin film blood smear, revealed a mature, Plasmodium malariae schizont. 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”.

生物学细菌

An electron microscopic (SEM) image, depicts a blue-colored, human white blood cell, (WBC) known specifically as a neutrophil, interacting with two pink-colored, rod shaped, multidrug–resistant (MDR), Klebsiella pneumoniae 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”.

实验室细菌

Novel Coronavirus SARS-CoV-2–Colorized scanning electron micrograph of a VERO E6 cell (blue) heavily infected with SARS-COV-2 virus particles (orange), 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”.

A 125X photomicrograph magnification of a hematoxylin and eosin (H&E)–stained lung tissue specimen, revealed the presence of cytoarchitectural changes indicative of a blastomycosis fungal infection. 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”.

MRI of my Brain

Pills Medicine

医疗药物健康

Motivated Student Girl

Pterodactyl

(Martine) Nurse

古老的水下

A 3D graphical representation of a number of Rotavirus 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”.

Karate

Medical Doctor Man

Bathing Woman is Drinking Wine

Redbreast sunfish-1

Eye of a Bluegill

Book and plant isolated on white background

Open book in green grass over blue sky

25 Thailand

Bluegill on nest-1

Bluegill on nest-2

Bluegill on nest-4

Strange looking white fish with black spots

Homework Text

Humpback chub

Cream Colored Fish

Redbreast sunfish-2

Bluegill on nest-2

12 Oman

Sea turtle swims in sea water

Alewife-1

Aspen Leaf

A medical illustration of drug–resistant, Neisseria gonorrhoeae 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”.

Apples on stack of books

建筑物餐饮

Wolverine

野生动物动物

Stegosaurus

野生动物动物

Male Student is Holding His Smartphone

EKG Monitors

心脏膈面医学

Woman is Bathing

Stop Coronavirus

Kids are Studying

孩子们学校

Hospital Building

建筑物建筑

Medical Doctor Man Acting as a Guide

Man Standing in front of an Electric Fan

Tropical Fish

beautiful bee sucking the juicy nectar

Piano lesson

Father and Son are Taking a Bath

Female Hands Typing On A Laptop Keyboard

Fish 2

Silly looking yellow fish

8 Oman

Fish Reflection Water Tank

Man is Thinking

cute little fish in an aquarium

Lionfish swimming in the Aquarium

leaf

leaf

Leaf

leaf

leaf

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