How cell parts work together to make and ship a protein

Grade 9 Science Worksheet - Challenge Me

Circle the best answer.

1. Read this first

   Use the table

   Cell cutaway (animal cell, model, not to scale). Letter A marks the rough ER (the flat folded sacs studded with tiny dots, joined to the wall of the large round body). Letter B marks the transport vesicle (a small bubble between the dotted sacs and the stack of curved smooth sacs). Letter C marks the Golgi apparatus (the stack of curved smooth sacs, away from the dotted sacs). Route in order: nucleus, nuclear pore, rough ER, transport vesicle, Golgi apparatus, secretory vesicle, plasma membrane. Pulse-chase card, read about only. Where most of the label is found (model data)

   cell	at 20 minutes	at 60 minutes
   normal cell	Golgi apparatus	outside the cell
   changed cell	transport vesicles	transport vesicles

2. 1.

   Ari sees that in the changed cell one job fails. Use the cutaway and the card. Which job fails?

   • The nucleus is not building the protein, so no label moves on
   • Vesicles are not delivering protein from the rough ER to the Golgi
   • The Golgi apparatus is not building the protein from amino acids
   • Secretory vesicles are not fusing with the plasma membrane at the cell edge
3. 2.

   Esme compares three gland cells with the route in the cutaway. Which statement does the card support?

   • Release depends on the Golgi apparatus, since the Golgi builds the protein
   • Release is highest in Z, since Z has the most rough ER
   • More rough ER and Golgi go with more release, as the route uses both
   • Release depends on the rough ER, since each part does its job on its own
4. 3.

   Jun sees no label outside the cell at 20 minutes, though the protein was made by 5 minutes. Why does this fit the route?

   • A vesicle is a fixed part that stores the protein until 60 minutes
   • The nucleus holds the finished protein until 60 minutes, then releases it
   • The rough ER works alone, so it needs 60 minutes to send it out
   • The protein is still on its way, passing several parts before release
5. 4.

   Kira sees that the changed cell makes the protein but releases almost none. Which explanation fits the card?

   • The nucleus is holding the finished protein inside and not releasing it
   • Vesicles are not carrying protein from the Golgi to the membrane
   • Transport vesicles are not delivering protein from the rough ER
   • The Golgi apparatus is not building enough of the protein to send on
6. 5.

   The count of vesicles near the membrane falls while protein outside rises. Luz asks where the vesicles went. Which explanation fits?

   • They returned to the rough ER to pick up more protein
   • They were used up making ATP, the cell’s energy molecule
   • They are permanent parts, so they moved out of view into the cytoplasm
   • They fused with the plasma membrane and released the protein

7. Use the table

   Pulse-chase card, read about only. Where the label was found (model data)

   minutes after labeling	most label found in
   5	rough ER
   25	Golgi apparatus

8. 6.

   Noah's class saw label in the Golgi apparatus at 25 minutes and concluded the Golgi built the protein. What is the flaw?

   • No flaw: label found in a part shows that part built the protein
   • The label should have been in the nucleus first, since the nucleus builds proteins
   • The Golgi cannot be tested, since each part works alone
   • The label was in the rough ER first, so the protein reached the Golgi already built

9. Rough ER counted in one slice of each cell (model data)

   cell	rough ER sacs
   gland cell	44
   muscle cell	10

10. 7.

    Pia's class counted rough ER in one gland cell and one muscle cell, then said every gland cell has more. Which flaw is in the conclusion?

    • Only one cell of each type was counted, so more cells are needed
    • Rough ER cannot be counted, because it is too small to see
    • The nucleus was not counted, and the nucleus builds the proteins
    • The counts do not matter, because each part works alone and the cell type cannot change them
11. 8.

    Cell cutaway (animal cell, model, not to scale). Ren says a protein released from the cell was first built by a free ribosome floating in the cytoplasm. Which response fits?

    • Agree: free ribosomes build them, then the Golgi ships them
    • Disagree: the nucleus builds the secretory proteins
    • Disagree: the Golgi apparatus builds the secretory proteins
    • Disagree: ribosomes on the rough ER make secretory proteins
12. 9.

    Tala says the Golgi apparatus could still pack proteins for release if the rough ER stopped making them. Which response is best?

    • Disagree: the vesicles are fixed parts that would keep delivering protein
    • Agree: the Golgi apparatus builds its own proteins to pack
    • Agree: each part works alone, so the Golgi needs no protein from the rough ER
    • Disagree: the Golgi packages proteins that arrive from the rough ER
13. 10.

    Cell cutaway (plant cell, model, not to scale). Zee says a leaf cell has chloroplasts (A), so its mitochondria (B) are not needed. Which response fits?

    • Agree: plant cells have no mitochondria
    • Disagree: mitochondria use the chloroplasts’ sugar to provide ATP
    • Disagree: mitochondria make the sugar that chloroplasts use
    • Agree: the chloroplast works alone and supplies the cell’s energy by itself