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The Excretory System

urinary system

kidney

urine

bladder

nephron

urethra

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What does the excretory system do?

excretory system

urinary system

kidney

urine

urinary system (yәr´ә ner´ē sist´әm) The part of the excretory system that handles most liquid wastes.

kidney (kid´nē) A bean-shaped organ that filters waste out of the blood.

urine (yәr´әn) A fluid consisting of body waste and excess water.

Start with the CALIFORNIA STANDARDS

5 LS 2.d. Students know the role of the kidney in removing cellular waste from blood and converting it into urine, which is stored in the bladder.

Main Idea

Have students talk about how wastes are removed from the body. Ask:

Which systems release wastes from the body?

Answers: digestive, respiratory, urinary, and integumentary

Develop Vocabulary

urinary system (yәr’ә ner’ē sis’tәm) The part of the excretory system that handles most liquid wastes. (p. 156)

The kidneys, bladder, and urinary tract are parts of the urinary system.

- Word Parts Ask students to find a definition for the suffix –ary. (Answer: of or relating to) Ask them to identify the part of speech urinary belongs to. (Answer: adjective ) Have students define urinary system using this information.

kidney (kid’nē) A bean-shaped organ that filters waste out of the blood. (p. 156)

The kidneys produce urine.

- Scientific vs. Common Use Ask students to speculate about the origin of the name kidney bean.

Possible answer: Kidney beans are shaped like kidneys.

urine (yәr’ әn) A fluid consisting of body waste and excess water. (p. 156)

The kidneys produce urine by filtering the blood.

- Word Origin Ask students to find the origin of the word urine. Answer: Latin, urina Ask students if they know any other words related to urine.

Possible Answers: urinal, urinalysis, urinate

Critical Thinking

What makes something a waste?

A waste is something that is not useful or can be harmful to the body.

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What does the excretory system do, pg. 156-157

Life Science: The Human Body

Name

Homeroom #

Date

Universal #

Science

Ch. 3,Lesson 5

pgs.156-162

Excretory system:

What makes something a waste?

What systems are part of the excretory system?

____________________________________________________________________________________________________________

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Life Science: The Human Body

Name

Homeroom #

Date

Universal #

Science

Ch. 3,Lesson 5

pgs.156-162

Urinary system:

Kidneys:

Liver:

Bladder:

Ureters:

Nephrons:

Urethra:

Urine:

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How does your body filter blood?

Kidney

renal artery

renal vein

ureter

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How does your body filter blood?

capillary

nephrons

artery

vein

collecting duct

Nephron

nephron

nephron (ne´frän´) one of many small individual filters within the kidneys.

Start with the CALIFORNIA STANDARDS

5 LS 2.d. Students know the role of the kidney in removing cellular waste from blood and converting it into urine, which is stored in the bladder.

Reading Diagrams

Where does the stored waste in the collecting duct go?

Clue: Look for the collecting duct to find what it is connected to.

Answer: The stored waste in the collecting duct moves to the ureter. The ureter moves the waste to the bladder.

Develop Vocabulary

nephron (ne’frän’) one of many small individual filters within the kidneys. (p. 158)

Nephrons separate waste from useful substances in the blood.

- Word Origin Tell students that the word comes from the Greek nephros. Ask students to write a sentence using the word.

Critical Thinking

Why are nephrons surrounded by capillaries?

Answer: Nephrons have a membrane that allows some particles to flow in and out. Waste products are kept inside nephrons and useful materials, such as nutrients, are carried back to the body in the blood through capillaries.

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How does your body eliminate waste?

Empty bladder

Full bladder

bladder

urethra

bladder (bla´dәr) An organ of the excretory system that temporarily stores urine.

urethra (yù rē´thrә) A tube that carries urine from the kidney to the bladder.

Start with the CALIFORNIA STANDARDS

5 LS 2.d. Students know the role of the kidney in removing cellular waste from blood and converting it into urine, which is stored in the bladder.

Reading Photos

Describe how the empty bladder and the full bladder are different.

Clue: Look at the highlighted part of the photos.

Answer: The empty bladder is much smaller than the full bladder.

Develop Vocabulary

bladder (bla’ dәr) An organ of the excretory system that temporarily stores urine. (p. 160)

The human bladder can increase in size to hold one and a half pints.

- Scientific vs. Common Use Ask students to find a common definition for bladder. Ask students if they have heard this word in any other contexts.

Possible answer: something that looks like a rubber sack; football bladder, air bladder

urethra (yù rē’thrә) A tube that carries urine from the bladder to the outside of the body. (p. 160)

The urethra is part of the excretory system.

- Word Origin Ask students to find the origin of urethra. Have students write sentences using urethra.

Answer: Greek; ourein, to urinate

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Life Science: Path Liquid Waste Travel in the Body:

Name

Homeroom #

Date

Universal #

Science

Ch. 3,Lesson 5

pgs.156-162

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Life Science: How a Nephron Works:

Name

Homeroom #

Date

Universal #

Science

Ch. 3,Lesson 5

pgs.156-162

What is the function of the ureters?

Where does the stored waste in the collecting duct go?

____________________________________________________________________________________________________________________________________________________________________________________

How does your body filter blood, pg. 158-159

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How does your body filter blood, pg. 158-159

Life Science: The Human Body

Name

Homeroom #

Date

Universal #

Science

Ch. 3,Lesson 5

pgs.156-162

What is the function of the liver?

What is a toxin?

What are the functions of the liver and kidneys?

Liver:

________________________________________________________________________________________________________________________

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How does your body eliminate waste?

capillary

sweat gland

hair

pore

Structure of Skin

Start with the CALIFORNIA STANDARDS

5 LS 2.d. Students know the role of the kidney in removing cellular waste from blood and converting it into urine, which is stored in the bladder.

Main Idea

Ask students to talk about sweat. Ask:

What is sweat?

Answer: Sweat contains water, excess salts, and other waste products.

What two jobs does sweat perform in your body?

Answer: eliminate waste and keeping the body cool

Use the Visuals

How are sweat glands related to the pores in the surface of the skin?

Answer: The sweat glands push sweat up to the pores in the surface of the skin.

What else do you see on the surface of the skin in this diagram?

Answer: Hair

Critical Thinking

How do urine and sweat leave your body?

Answer: Urine leaves the body through the urethra. Sweat leaves the body through pores in the skin.

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Life Science: The Human Body

Name

Homeroom #

Date

Universal #

Science

Ch. 3,Lesson 5

pgs.156-162

What two jobs does sweat perform in your body?

How are the sweat glands related to the pores in the surface of the skin?

Integumentary system:

________________________________________________________________________________________________________________________________________________

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Life Science: The Human Body

Name

Homeroom #

Date

Universal #

Science

Ch. 3,Lesson 5

pgs.156-162

The Excretory system:

Connected body systems:

Organs:

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What happens if the kidneys stop working?

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Life Science: The Human Body

Name

Homeroom #

Date

Universal #

Science

Ch. 3,Lesson 5

pgs.156-162

What is the function of healthy kidneys?

What is the function of dialysis and why do people need it?

What happens if the kidneys stop working, pg. 162

Summary: