42,648 免费图片适用于学生

绿色性质生物学植物植物学植物群树叶叶子生长生长

leaf

Leaf

Green Background of Leaf

Leaves

建筑物医学

Businessman Thinks

实业家思维

Pharmacist Chemists Drug

医疗药物女人

Fern foliage -7

Toilet paper

View of Dhaka from the International Space Station in Bangladesh

外层空间河流

Hospital Face Mask 2

Ash Meadows Amargosa pupfish-1

Northeastern beach tiger beetles

节肢动物动物

The seven original Mercury astronauts

My abdominal aorta and iliac artery aneurysms

Pills Medicine

医疗药物健康

Cacapon mussel survey-3

5 Oman

Hellbender-1

leaf

leaf

leaf

leaf

Green Floral Leaves

Green Macro Leaf

leaves

7 Oman

FWS divers search for salamanders in Spring Lake-2

Fish Tank

Coral reef

leaf

Ecology Book

Male Student is Thinking

洗发精

卫生学肥皂

Velociraptor

Woman is Taking a Bath

Coral Water Tank Fish

Green Apple on Book

建筑物餐饮

Green apple on books

建筑物餐饮

Tylosaurus dinosaur

爬行动物动物

Doctor is Giving Advice

商界女强人在想

Child Home

Water Dragon

Rabbit Teacher with Bear Student in the Class

Bluegill on nest-1

Leaves

School Boy is Studying

小男孩儿童

Boy is Washing His Hair

Toothbrush, Toothpaste, and Cup

玻璃容器浴室

Lake monster

程序员

电子计算机人

Willow

Close up of lady's slipper orchid Paphiopedilum

Close up of lady's slipper orchid Paphiopedilum

Where there is a will, there is a way

Long-Billed curlew

Surgical nurse, Herrin Hospital (private), Herrin, Illinois (1939).

Laboratory technician working with a cell culture solution, using a syringe to add some of the sample to a glass bottle. A healthcare provider donning a pair of green latex gloves in order to protect herself during her subsequent interaction her next patient. 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

Wildlife field forensics

Juvenile Chinook salmon-2

A medical illustration of drug–resistant, Mycoplasma genitalium 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”.

A 3D image of a group of Gram–positive, Corynebacterium diphtheriae, 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”.

India and Ceylon as seen from the orbiting Gemini-11 spacecraft.

天文学行星

A Petri dish culture plate containing a growth medium of Sabouraud dextrose agar, which had been inoculated with the fungal organism from the genus, Syncephalastrum, strain A-423. 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”.

Videographer films biologists

Cloth Soap

Spaceship detail with American flag in hangar

Fossil of dinosaur footprint

Photographing Girl

孩子们技术

医生和孕妇

Mother and Daughter are Taking a Bath

Student Couple

Bio Hazard

生化危机符号

Couple of Students

Student Couple

Turtle Dove

Male Student is happy

Couple of Students

Student Couple

Baobab

Worried Businessman

实业家思维

Pharmacist Woman

医疗药物女人

Medical Doctor Woman is Holding a Syringe

Stop Coronavirus

T-Rex Skeleton

Leaf

Close up of lady's slipper orchid Paphiopedilum

Great Barracuda - Sphyraena barracuda

Frog Green

Frog Animal

伶盜龍

Female nurse

专业领域人

Volcano

Green Herb Leaves

Green Herb Leaves

Fresh Green Lettuce

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