Science MCQs

Practice multiple choice questions with instant feedback. Select an option to see if you're correct.

Total Questions
2100
Page 14 of 210
Question 131 Medium

Anaerobic respiration in muscles produces:

A
Alcohol
B
Lactic acid
C
Oxygen
D
Glucose
Question 132 Medium

Which blood vessel carries oxygenated blood from the lungs to the heart?

A
Pulmonary artery
B
Pulmonary vein
C
Aorta
D
Coronary artery
Question 133 Easy

What is the function of valves in veins?

A
To increase blood pressure
B
To prevent backflow of blood
C
To produce red blood cells
D
To filter impurities
Question 134 Easy

Which part of the heart pumps blood to the entire body?

A
Right atrium
B
Left ventricle
C
Right ventricle
D
Left atrium
Question 135 Easy

What is the main component of plasma in blood?

A
Hemoglobin
B
Water
C
Platelets
D
Oxygen
Question 136 Easy

Which blood cells are responsible for fighting infections?

A
Red blood cells
B
White blood cells
C
Platelets
D
Plasma
Question 137 Easy

What gives red blood cells their color?

A
Plasma
B
Hemoglobin
C
Oxygen
D
Carbon dioxide
Question 138 Medium

How long do red blood cells typically survive in the bloodstream?

A
7 days
B
30 days
C
120 days
D
1 year
Question 139 Easy

What is hypertension?

A
Low blood pressure
B
High blood pressure
C
Rapid heart rate
D
Low oxygen levels
Question 140 Medium

Which of the following is NOT a symptom of a heart attack?

A
Chest pain
B
Shortness of breath
C
Increased appetite
D
Sweating
Showing 131-140 of 2100 questions

Quick Stats

Total Questions 10900
easy 5797
medium 2983
hard 2120

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