Biology Now, 2e

70 ■ CHAPTER 04 Life Is Cellular

CELLS

Nuclear envelope

Nucleus

Endoplasmic

reticulum (ER)

Nuclear pores

DNA

Smooth

ER

Rough

ER

Ribosomes

Smooth ER is a site for lipid

and hormone manufacture.

All eukaryotes

contain their

DNA within a

nucleus, the

control center

of the cell.

With its embedded

ribosomes, rough ER is a site

for protein production.

Golgi

apparatus

Free transport

vesicle

Transport

vesicle

being formed

Proteins and lipids are chemically

modified as they move from one part

of the Golgi apparatus to the next.

Lysosomes function as cellular

“recycling centers,” breaking down

molecules no longer needed by the cell.

Lysosomes