functions of cell organelles

Question 1

what is the function of the plasma membrane?

Answer 1

Separation of intracellular vs. extracellular materials
Production of charge difference (membrane potential) across the membrane by regulation of intracellular and extracellular ion concentrations

Question 2

What is the function of cytoplasm

Answer 2

-cytoplasm is general term for all material inside of cell. proteins are 15-30 percent of weight of cell.
-cytoplasm includes 2 subdivisions
Cytosol(intracellular fluid)- contains dissolved nutrients, ions,soluble, insoluble proteins and waste products
organelles- intracellular structures with very specific tasks

Question 3

What is Endocytosis? what is phagocytosis and pinocytosis?

Answer 3

Endocytosis- packaging extracellular materials into vesicle for importation into cell.
Phagocytosis-“cell eating” vesicles form at plasmalemma to bring solid particles into cell
Pinocytosis-“ cell drinking”-vesicles form at plasma lemma and bring extracellular fluid and small molecules into cell.

Question 4

what is exocytosis? give 3 examples

Answer 4

• release fluids and/or slide from cells when intracellular vesicles fuse with plasmalemma
  ex: cellular waste built up in cell ejected from vesicles

Question 5

what is the function of cytoskeleton?

Answer 5

• framework fibres gives cell strength and flexibility
• 4 major components
  1. Microfilaments- slender strands made mostly of protein actin. major functions are to anchor cytoskeleton to important proteins of plasmalemma. function stabilizes position of membrane proteins, provides extra strength to cell.

2. intermediate filaments-provide strength, stabilize position of organelles, and transport materials within cytoplasm. ex intermediate filaments called neurofilaments found in nerves. provide structural support within axons.
3. thick filaments- massive filament composed myosin. abandoned in muscle cells where they interact with actin filaments to produce powerful contractions.
4. Microtubules-hollow tubes formed from protein tubular. functions include
   - primary components of cytoskeleton, gives strength and rigidity and anchoring positions of major organelles
   - assemble/dissasemble microtubules provide mechanism for changing shape of cell, assisting cell movement
   - attach to organelles other intracellular materials move them around within cell
   - form structural components organelles such centrioles,flagella,cilia,

Question 6

What are organelles and what do they do ?

Answer 6

• small specialized structures with particular functions
• most have membranes that separate inferior of organelles from cytoplasm
• related to specific structure and function of cell

Question 7

What is the function of the Nucleus?

Answer 7

• control center for all operations
• determines structural and functional characteristics of cell by controlling proteins synthesized, and in what amounts
• nuclear envelope surrounds nucleus separates from cytosol.
• nuclear pores are chemical communication between uncles and cytosol. complex proteins move macromolecules into and out of nucleus. permit movement water,ions,small molecules regulate passage larger proteins like RNA DNA.

Question 8

What is the Nucleus?

Answer 8

organelle of a cell

Question 9

What is the function of cilia?

Answer 9

Appendages projecting from cell surfaces
Capable of movement
Moves materials over the cell surface
-non membrane(1 of 3)

Question 10

what are the functions of centrioles and spindle fibers?

Answer 10

Located in centrosome: specialized zone near nucleus
Center of microtubule formation
Before cell division, centrioles divide, move to ends of cell and organize spindle fibe`

Question 11

Function of flagella? 1 example

Answer 11

• similar to cilia but longer
• usually 1 per cell
• move in wavelike fashion,
• example: sperm cell
• non membrane bound (1 of 3)

Question 12

what is the function of microvili

Answer 12

• extension of plasma membrane
• increases cell surface area
• normally many on each cell
• 1/10 1/20 size cilia
• Non membrane bound (1 of 3)

Question 13

what is the function of ribosomes

Answer 13

• site of protein synthesis
• composed small and large sub unit
• attached to ER

Question 14

Function of Rough and Smooth Er?

Answer 14

• Rough ER produces proteins

- smooth ER produces fats

Question 15

what is the function of the Golgi Apparatus

Answer 15

• synthesize and package of secretions like mucins or enzymes
• packaging special enzymes for use in cytosol
• renewal or modification of plasmalemma

Question 16

what are the functions of peroxisomes and proteasomes?

Answer 16

Peroxisomes
Smaller than lysosomes
Contain enzymes to break down fatty acids and amino acids
Hydrogen peroxide is a by-product of breakdown
Proteasomes
Consist of large protein complexes
Include several enzymes that break down and recycle proteins in

Question 17

What is the function of mitochondria

Answer 17

Major site of ATP synthesis
Membranes
Cristae: Infoldings of inner membrane
Matrix: Substance located in space formed by inner membrane
Mitochondria increase in number when cell energy requirements increase.
Mitochondria contain DNA that codes for some of the proteins needed for mitochondria production.

Question 18

what is gross or microscopic anatomy?

Answer 18

structures examined without a microscope present
-Cytology: cellular anatomy
Histology: study of tissues

Question 19

what is regional, systematic and surface anatomy?

Answer 19

• regional: studied by area
• systemic: studied system by system
• surface:external form and relation to deeper structures as x-ray in anatomic imaging

Question 20

What is pathology?

Answer 20

structure and functional changes caused by disease

Question 21

what is exercise physiology?

Answer 21

strucure and functional changes caused by exercise

Question 22

what are the structural and functional organizations?

Answer 22

Chemical Level: interaction of atoms
Cell Level: functional unit of life
Tissue Level: group of similar cells and the materials surrounding them
Organ Level: one or more tissues functioning together
Organ System Level: group of organs functioning together
Organism Level: any living thing.

Question 23

what are the characteristics of life and their functions?

Answer 23

Organization: condition in which there are specific relationships and functions
Metabolism: all chemical reactions of the body
Responsiveness: ability to sense changes and adjust
Growth: increase in size and/or number of cells
Development: changes in an organism over time
Differentiation: change from general to specific
Morphogenesis: change in shape of tissues, organs
Reproduction: new cells or new organisms

Question 24

Basic structures of cell are?

Answer 24

Plasma membrane
Cytoplasm containing organelles
Nucleus

Question 25

Functions of cell are?

Answer 25

Basic unit of life
Protection and support through production and secretion of various kinds of molecules
Movement. Various kinds occur because of specialized proteins produced in the cell
Communication. Cells produce and receive electrical and chemical signals
Cell metabolism and energy release
Inheritance. Each cell contains DNA. Some cells are specialized to gametes for exchange during sexual intercourse

Question 26

what are functions lysosomes?

Answer 26

-vesicles filled digestive enzymes formed by rough ER
primary lysosomes-inactie proteins
secondary lysosomes- contain activated enzymes
-defend against disease
- clean up and recycle functions in cell