Chapter 3 Pt. 3 Flashcards
The ________ contains almost all of the cell’s genetic information
nucleus
What is a nuclear envelope?
a double membrane that surrounds the nucleus and separates it from the cytoplasm
What are nuclear pores?
openings in the envelope where communication between the nucleus and cytoplasm occur
____________ are threadlike structures made of DNA and associated proteins
Chromosomes
the ________ of chromosomes varies from one species to another
number
What are chromatin?
genetic material in a dispersed state
the chromatin and other contents of the nucleus constitute the __________
nucleoplasm
What is the nucleolus?
a specialized region within the nucleus, forms and disassembles during the course of the cell cycle
The nucleolus is not surrounded by a membrane but is simply a region where DNA has gathered to produce a type of RNA called ________ _____ (_____)
ribosomal RNA (rRNA)
What are ribosomes?
sites where protein synthesis begins
_________ ____ is a component of ribosomes
Ribosomal RNA
Ribosomes may be suspended in the _________ (free ribosomes) or attached to the __________ _________ (bound ribosomes)
cytoplasm
endoplasmic reticulum
Ribosomes may be suspended in the cytoplasm (_____ _________) or attached to the endoplasmic reticulum (_______ _________)
(free ribosomes)
bound ribosomes
What is endoplasmic reticulum (ER)?
is part of an extensive network of channels connected to the nuclear envelope and certain organelles
The endoplasmic reticulum (ER) is studded with _________.
ribosomes
Proteins made by ribosomes bound to ER will be incorporated into __________ or eventually ________ by the ____
membranes
secreted
cell
Proteins produced by ____ _________ (cytoplasm) will remain in the cell
free ribosomes
Proteins produced by free ribosomes (________) will remain in the cell
cytoplasm
smooth endoplasmic reticulum (SER) lacks _________
ribosomes
______ _________ ________ (____) detoxifies alcohol and other drugs
smooth endoplasmic reticulum (SER)
smooth endoplasmic reticulum (SER) produces ____________
phospholipids
SER is used to make the ____ _________ (which must be replenished constantly)
RER membrane
What is the Golgi complex?
the cell’s protein processing and packaging center
The ______ ________ consists of a series of interconnected, flattened membranes sacs
Golgi complex
What are lysosomes?
roughly spherical organelles consisting of a single membrane packed with about 40 different digestive enzymes
When a cell engulfs a bacterium:
(1)
(2) lysome fuses with vesicle containing bacterium
(3) lysosomal enzymes break the bacterium down into smaller molecules that diffuse into cytoplasm
(4) some indigestible substances leave the cell by exocytosis
(5) other indigestible substances remain in the cell
(1) Cell engulfs bacterium through phagocytosis
When a cell engulfs a bacterium:
(1) Cell engulfs bacterium through phagocytosis
(2)
(3) lysosomal enzymes break the bacterium down into smaller molecules that diffuse into cytoplasm
(4) some indigestible substances leave the cell by exocytosis
(5) other indigestible substances remain in the cell
(2) lysome fuses with vesicle containing bacterium
When a cell engulfs a bacterium:
(1) Cell engulfs bacterium through phagocytosis
(2) lysome fuses with vesicle containing bacterium
(3)
(4) some indigestible substances leave the cell by exocytosis
(5) other indigestible substances remain in the cell
(3) lysosomal enzymes break the bacterium down into smaller molecules that diffuse into cytoplasm
When a cell engulfs a bacterium:
(1) Cell engulfs bacterium through phagocytosis
(2) lysome fuses with vesicle containing bacterium
(3) lysosomal enzymes break the bacterium down into smaller molecules that diffuse into cytoplasm
(4)
(5) other indigestible substances remain in the cell
(4) some indigestible substances leave the cell by exocytosis
When a cell engulfs a bacterium:
(1) Cell engulfs bacterium through phagocytosis
(2) lysome fuses with vesicle containing bacterium
(3) lysosomal enzymes break the bacterium down into smaller molecules that diffuse into cytoplasm
(4) some indigestible substances leave the cell by exocytosis
(5)
(5) other indigestible substances remain in the cell
What happens when lysosomes digest the obsolete parts of the cell?
(1) lysosome engulfs a damaged organelle
(2) lysosomal enzymes break down the organelle into smaller molecules that will return to the cytoplasm for reuse
True or False: single kind of lysomal can be absent within the cell and still function
False; it can have devastating consequences
Lysomal storage diseases are ________ and progress with ____.
inherited
age
What is an example of a lysomal storage disease?
Tay-Sachs disease
What is Tay-Sachs disease?
caused by the absence of the lysosomal enzyme hexosaminidase (Hex A) which breaks down lipids in nerve cells
Tay-Sachs disease, by 4 to 5 years old it can cause _______ and ______
paralysis
death
True or False: There is no cure for Tay-Sachs disease
True
