Unit 5- Intracellular Activities Flashcards Preview

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Flashcards in Unit 5- Intracellular Activities Deck (165)
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1

All internal workings within cells must be _______.

Organized

2

What are the methods of organizing the cell?

Large, Multi-protein complextes Membrane-Enclosed Organelles

3

Nucleus

contains main genome, surrounded by nuclear envelope, nuclear pores facilitate communication between interior of nucleus and cytosol

4

Endoplasmic Reticulum

interconnected network of sacs and tubes, continuous with nuclear envelope; site of synthesis of membranes for cell and major site of protein modification (ER lumen)

5

Rough ER

has bound ribosomes, nascent proteins are delivered to rER membrane or into ER lumen

6

Smooth ER:

no ribosomes, major functions vary between cells types

7

Endocrine cells function:

Steroid Hormone Synthesis

8

Liver Cells Function:

Detoxification of alcohol and other organics

9

Muscle Cells Function

The site of Ca2+ Storage

10

Gogli Apparatus

receives proteins and lipids from ER and modifies them, dispatches them to destination

11

Lysosomes

degrade worn out organelles (autophagy), macromolecules and engulfed material

12

Endosomes

sort and dispatch engulfed material to destination, also may recycle it back to plasma membran

13

Peroxisomes

break down lipids and destroy toxic molecules using variety of oxidative reactions

14

Mitochondria

Energy synthesis

15

Membranous Organelles are held in place by the _______

cytoskeleton: serves as tracks along which organelles move

16

Membranous Organelles are Thought to have evolved in _________ through series of ________.

Eukaryotic Ancestor Invaginations

17

Non-membranous organelles treat interior of organelles as ______

Exterior

18

The Endomembrane system is composed of:

Composed of Nuclear Envelope, ER, Golgi, Lysosomes, Endosomes, Peroxisomes

19

Interiors of ES organelles communicate with each other via ______ that bud from one organelle/plasma membrane and fuse with next organelle or to plasma membrane

Vesicles

20

Protein content, both in lumen and membrane proteins, of organelles determines ______

Functions

21

Protein sorting occurs by what 3 mechanisms?

Through nuclear pores Transported across membranes Transport by vesicles

22

Pritein sorting is controlled by ___ ____ ______ of cargo proteins themselves (____ _____)

Amino Acid Sequence Signal sequences

23

Describe Transport through nuclear pores

Movement in/out of nucleus Pores penetrate both inner and outer nuclear membranes andfunction as selective gates that actively transport material across

24

Describe Transport across membranes

• Movement into ER, Mitochondria, some entry into Peroxisomes • Requires protein translocators, which facilitate movement

25

Describe Transport by vesicles

• Movement from one compartment of ES to next • Requires transport vesicles which carry cargo proteins and pinch off from one membrane and fuse with the next

26

Define: Signal Sequence

stretch of few (4) up to 50 AA in primary sequence of protein that directs protein • Often removed from sorted protein

27

The Nuclear Envelope is double-_______

membraned.

28

Inner Membrane of Nuclear Envelope:

Contains attachmetn sites (proteins) for certain regions of chromosomes and is associated with nuclear lamina

29

nuclear lamina

cage-like network of proteins, give shape to nucleus

30

Outer Membrane of Nuclear Envelope:

continuous with and similar to ER Membrane