Chapter 3 Cellular level of organization

Question 1

What is the plasma membrane?

Answer 1

Forms the cells outer boundary, and separates the cell’s internal environment form the outside environment

Question 2

What role does the plasma membrane play?

Answer 2

selective barrier which plays a vital role in cellular communication

Question 3

What is the cytoplasm?

Answer 3

All the cellular contents between the plasma membrane and the nucleus

Question 4

What is the cytosol?

Answer 4

The fluid portion of a cell, mostly, water

Question 5

What are organelles?

Answer 5

Subcellular structures having characteristic shapes and specific functions

Question 6

What is the nucleus?

Answer 6

Large organelle that contains DNA , each of which consists of a single molecule of DNA and associated proteins

Question 7

A chromosome contains thousands of hereditary units called what?

Answer 7

Genes

Question 8

What is the fluid mosaic model?

Answer 8

The arrangement of molecules within the membrane resembles a sea of lipids containing many types of proteins

Question 9

What acts as barrier to certain substance in a plasma membrane?

Answer 9

Lipids

Question 10

Proteins act as what to certain molecules and ions

Answer 10

Gatekeepers

Question 11

What is the lipid bilayer made up of?

Answer 11

1.Phospholipids
2. cholesterol
3. Glycolipids

Question 12

What are integral proteins?

Answer 12

Extend into or through the lipid layer

Question 13

What are transmembrane proteins?

Answer 13

Most integral proteins, span the entire lipid bilayer

Question 14

What are peripheral proteins?

Answer 14

Attached to the inner or outer surface of the membrane, do not extend through it

Question 15

Is the cell membrane permeable?

Answer 15

It is depending on the substance

Question 16

What is the lipid bilayer permeable to?

Answer 16

1. Oxygen
2. Carbon dioxide
3. water
4. Steroids

Question 17

What is the glucose bilayer not permeable to?

Answer 17

Glucose

Question 18

What does the transmembrane proteins do?

Answer 18

Act as channels and transporters to assist the entrance of certain substances. For example, glucose and ions

Question 19

What is the cytoskeleton of a cell?

Answer 19

Network of protein filaments throughout the cytosol, which provides structural support for the cell

Question 20

What are different types of cytoskeleton?

Answer 20

1. Microfilaments
2. Intermediate filaments
3. Microtubules

Question 21

What is the centrosome?

Answer 21

located near the nucleus, consists of two centrioles and pericentriolar material

Question 22

What are cilia?

Answer 22

Short hair like projections from the cell surface, move fluids along a cell surface

Question 23

What are flagella?

Answer 23

Longer than cilia, move an entire cell; an example is the sperm cells tail

Question 24

What are ribosomes?

Answer 24

Sites of protein synthesis

Question 25

What is the endoplasmic reticulum?

Answer 25

Network of membranes in the shape of flattened sacs or tubules

Question 26

What is a rough endoplasmic reticulum?

Answer 26

Connected to the nuclear envelope, and series of flattened sacs, surface is studded with ribosomes, produces various proteins

Question 27

What are smooth Endoplasmic reticulum

Answer 27

A network or membrane tubules, does not have ribosomes, synthesizes fatty acids and steroids, detoxifies certain drugs

Question 28

What is the Golgi complex?

Answer 28

Consists of 3-20 flattened, membranous sacs called cisternae. which modify, sort, and package proteins for transport to different destinations. The proteins are transported by various vesicles

Question 29

What are lysosomes?

Answer 29

Vesicles that form from the Golgi complex, contain powerful digestive enzymes

Question 30

What are mitochondria?

Answer 30

Powerhouse of the cell, they generate ATP

Question 31

Where are mitochondria more prevalent?

Answer 31

Physiologically active cells like 1. muscles 2. liver 3. kidneys

Question 32

What are cristae?

Answer 32

Series of folds of the inner membrane?

Question 33

What are matrix?

Answer 33

Large central fluid filled cavities

Question 34

What is the nuclear envelope?

Answer 34

A double membrane that separates the nucleus from the cytoplasm

Question 35

What are nuclear pores?

Answer 35

Numerous openings in the nuclear envelope, control movement of substance between nucleus and cytoplasm

Question 36

What is the nucleolus?

Answer 36

Spherical body that produces ribosomes

Question 37

What are genes?

Answer 37

The cells hereditary units, controls activities and structures of the cell

Question 38

What are chromosomes?

Answer 38

Long molecules of DNA combined with protein molecules

Question 39

What is passive processes?

Answer 39

Substances move across cell membranes without the input of any energy; use the kinetic energy of individual molecules of ions

Question 40

What are active processes?

Answer 40

When cells uses energy, primarily from the breakdown of ATP, to move a substance across the membrane. IE against a concentration gradient

Question 41

What are the four type of passive transport?

Answer 41

1. simple diffusion 2. Facilitated diffusion 3. Osmosis 4. filtration

Question 42

What is osmosis?

Answer 42

Net movement of water through a selectively permeable membrane from an area of high concentration of water (lower concertation of solutes) to one of lower concentration of water.

Question 43

What are two ways to get through the plasma membrane?

Answer 43

1. Through lipid bilayer by simple diffusion 2. Through aquaporins, integral membrane proteins

Question 44

What is tonicity?

Answer 44

A measure of the solutions ability to change the volume of cells by altering their water content

Question 45

What is hyportonic?

Answer 45

A solution that has a lower concentration of solutes than the cytosol inside the cell

Question 46

What is Hypertonic?

Answer 46

A solution has a higher concentration of solutes than does the cytosol inside the cell

Question 47

What is filtration?

Answer 47

Movement of water and dissolved substance from an area of high pressure to an area of low pressure

Question 48

What is an example of filtration in the body?

Answer 48

capillary beds in the kidneys moving small ions from blood stream and leaving larger protein molecules in bloodstream.

Question 49

What is active transport?

Answer 49

Movement of molecules across a membrane from area of low concentration to area of high concentration

Question 50

What does active transport require?

Answer 50

ATP

Question 51

What are three types of active transport?

Answer 51

1. Active transport pumps 2. Endocytosis 3. exocytosis

Question 52

What is an example of active transport pumps?

Answer 52

Sodium potassium pumps

Question 53

What is a vesicle?

Answer 53

A small spherical sac formed by budding off from a membrane

Question 54

What is endocytosis?

Answer 54

When materials move into a cell in a vesicle formed from the plasma membrane

Question 55

What are three types of endocytosis?

Answer 55

1. receptor mediated endocytosis 2. Phagocytosis 3. Bulk phase endocytosis

Question 56

What is exocytosis?

Answer 56

Vesicles fuse with the plasma membrane, releasing their contents into the extracellular fluid