Chapter 3.3 - Cell organelles Flashcards Preview

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Flashcards in Chapter 3.3 - Cell organelles Deck (40)
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1
Q

What is the primary function of the nucleus?

A

Storage and transmission of genetic information to the next generation of cells

-also used to synthesize the proteins necessary for cell function

2
Q

Surrounding the nuclus is a barrier called the ______ composed of ______

A

Surrounding the nuclus is a barrier called the nuclear envelope composed of two membranes

3
Q

At regular intervals along the surface of the nuclear envelope the two membranes are joined to each other, forming the rims of circular openings known as ______

A

At regular intervals along the surface of the nuclear envelope the two membranes are joined to each other, forming the rims of circular openings known as nuclear pores

4
Q

Nuclear pores allow the movement of ______ and _____ between the nucleus and cytoplasm

A

Nuclear pores allow the movement of RNA and Proteins that modulate gene expression between the nucleus and cytoplasm

5
Q

WIthin the nucleus, DNA, in association with proteins, forms a fine network of threads: ______

A

WIthin the nucleus, DNA, in association with proteins, forms a fine network of threads: chromatin

6
Q

During cell division, the chromatin threads become tightly condensed, forming rodlike bodies known as ______

A

During cell division, the chromatin threads become tightly condensed, forming rodlike bodies known as chromosomes

7
Q

Inside the nucleus is a densely staining filamentous region without a membrane called the

A

Nucleolus

8
Q

What is the purpose of the nucleolus?

(lecture)

A

Synthesis of ribosomal RNA

9
Q

What is the function of nuclear pores?

(lecture)

A

Allows selective movement of molecules in and out of the nucleus

-communication with cytosol

10
Q

Lecture definition of chromatin?

A

Consists of DNA associated with proteins

-condenses to form chromosomes during cell division

11
Q

Lecture definition of Nuclear envelope?

A

Double layered porous membrane

-separates nucleus from cytoplasm

12
Q

Most cells have one nucleus

Except (2)

A
  1. Red blood cells: have no nucleus (maximize space for hemoglobin)
  2. Skeletal muscle tissue: multinucleate
    • Made of many precursor cells fused together to form one large cell with many nuclei
13
Q

Ribosomes are responsible for:

A

Protein synthesis

“protein facotries of a cell”

14
Q

Ribosomes are composed of:

A

Two subunits: Large and small

15
Q

Each subunit of the ribosome is composed of _____ and ________

A

Each subunit of the ribosome is composed of proteins and ribosomal RNA

16
Q

The subunits of ribosomes join prior to ______, forming _____ ribosomes

A

The subunits of ribosomes join prior to protein synthesis, forming functional ribosomes

17
Q

What are the two major types of functional ribosomes?

A

Free ribosomes- in cytoplasm

Bound ribosomes - on Endoplasmic Reticulum

18
Q

What is the endoplasmic reticulum?

A

Fluid filled membranous system distributed throughout the cytoplasm

19
Q

What are the functions of the Rough endoplasmic Reticulum?

A
  • Synthesis of proteins with bound functional ribosomes
  • Post-translational modification of proteins
    • includes cleavage and glycosylation
    • needed to make membranes
    • needed for secretory proteins
20
Q

What are the functions of the smooth endoplasmic reticulum?

A
  • Synthesize lipids (fatty acids, steroids)
  • Stores Ca2+ (in muscle cells = sarcoplasmic reticulum)
  • Drug detoxification (liver cells)
21
Q

The _____ is a series of closely apposed, flattened membranous sacs that are slightly curved, forming a cup-shaped structure

A

The Golgi Apparatus is a series of closely apposed, flattened membranous sacs that are slightly curved, forming a cup-shaped structure

22
Q

What are cisternae?

A

Sets of flattened slightly curved membrane bound sacs stacked in layers (make up the golgi)

23
Q

What are the functions of the Golgi Apparatus?

A
  • Post-translational modification of proteins made in the RER
  • Sorts and packages proteins
24
Q

What are three options for proteins following packaging in the golgi?

A
  • Secreted via exocytosis
  • Become integral membrane proteins
  • become proteins of lysosomes, ER, or Golgi
25
Q

What are lysosomes?

A

Small, spherical organelles containing digestive enzymes

26
Q

What is the function of lysosomes?

A

Breakdown extracellular and intracellular debris

-Destroy endocytosed bacteria, viruses

27
Q

What pH do lysosomes function at, how is the pH maintained?

A

pH of 5, maintained by protein pumps

28
Q

How are lysosomes made?

A

Enzyme made in ER -> Golgi packages them into vesicles -> enzyme filled vesicle = lysosome

29
Q

What are peroxisomes?

A

Small organelles containing oxidative enzymes

30
Q

What is the function of Peroxisomes?

A

Use oxygen to remove hydrogen from molecules

-Breakdown longchain fatty acids, alcohol, drugs (abundant in liver & kidney)

31
Q

What is a toxic product from peroxisomes? How do peroxisomes combat this?

A

H2O2

Peroxisomes contain the antioxidant enzyme, catalase that breaks H2O2 into water and oxygen

32
Q

What two organelles have 2 membranes?

A

Mitochondria and Nucleus

33
Q

The inner membrane of the mitochondria folds to form:

A

Cristae

34
Q

What are four cell types that have an abundance of Mitochondria?

A

Skeletal muscle

Heart muscle

Liver

Sperm

35
Q

Mitochondria has its own DNA. What type of DNA is this?

A

Double stranded circular DNA

36
Q

What are three general functions of the cytoskeleton?

A
  1. Maintain cell shape
  2. Maintain Organelle position
  3. Mediate cell and organelle motility
37
Q

What are the three cytoskeletal filaments?

A
  1. Microfilament (actin filament)
  2. Intermediate filament
  3. Microtubule
38
Q

What is the protein subunit of microfilaments?

Function (3)?

A

G-actin

  • -Support cell,
  • determine cell shape
  • cell movement
39
Q

What is the protein subunit of intermediate filaments? What are three functions

A

There are several, including Keratin

  • intermediate filaments are part of desmosomes (via keratin)
  • Support cell,
  • Provide mechanical strength
  • desmosomes
40
Q

What is the protein subunit of microtubules?

What are 2 functions?

A

Tubulin = large hollow tubes

  • support for cell
  • movement of organelles (tracks)