ch03 cellular level of organization

Question 1

What is the plasma membrane?

Answer 1

flexible barrier that surrounds and contains cytoplasm of the cell

Question 2

what is plasma membrane constuctued of?

Answer 2

a fluid mosaic made up of a lipid bilayer

Question 3

what are amphipathic molecules?

Answer 3

molecules that have both charged and uncharged parts to the head and tails

Question 4

the 2 types of membrane proteins

Answer 4

Integral(transmembrane), peripheral

Question 5

What are integral proteins?

Answer 5

extend into or across the entire lipid bilayer

Question 6

what are peripheral proteins?

Answer 6

only found on the outer surface of the membrane and can broken away without disturbing membrane integrity

Question 7

what are function of membrane proteins

Answer 7

function as ion channels, carriers, receptors, enzymes, linkers and cell-identity markers

Question 8

def: selectively permeable

Answer 8

membrane allowing small, nonpolar uncharged molecules to pass by without the use of membrane proteins
involved

Question 9

what is concentration gradient?

Answer 9

different of conc of a chemical between one side of membrane and the other side

Question 10

Which membrane protein is involved with the transport of molecules that otherwise would be unable to enter the cell?

Answer 10

carrier proteins

Question 11

what is it called when the inner surface of the membrane is more -charged and the outer surface is more +charged

Answer 11

electrical gradient

Question 12

when both gradients are combined its called

Answer 12

electrochemical gradient

Question 13

name the 3 passive processes

Answer 13

simple diffusion, faciliated diffusion and osmosis

Question 14

name the 2 active processes

Answer 14

Primary and secondary transport, vesicular transport

Question 15

diffusion

Answer 15

random mixing of particles that occur in solution due to kinetic energy(passive)

Question 16

simple diffusion

Answer 16

nonpolar hydrophobic molecules diffuse across lipid bilayer without the need to transport protein

Question 17

facilitated diffusion

Answer 17

transmembrane(integral) moves solutes over lipid bilayer that are too polar

Question 18

Channel-mediated facillitated diffusion

Answer 18

solute moving down a concrete gradient through a membrane channel(most channels are ion channels)

Question 19

Carrier-mediated facilitated diffusion

Answer 19

solute binding to specific transporter on one side of membrane and is released on the other side

Question 20

osmosis

Answer 20

movement os solvent through a selectively permeable membrane from an area of high concentration to low conc

Question 21

TorF: the difference between simple and facilitated diffusion is that facilitated diffusion requires a membrane protein and simple diffusion doesn’t need one

Answer 21

True

Question 22

Tonicity

Answer 22

how the solution infulences the shape of body cells

Question 23

3 types of tonicity

Answer 23

hypertonic,isotonic,hypotonic

Question 24

def: Hypotonic

Answer 24

lower conc and more dilute than body fluids (hypo=hippo fat) 0.45% NaCl

Question 25

def: isotonic

Answer 25

same conc of particles as the intra and extracellular fluids 0.9% NaCl

Question 26

def: hypertonic

Answer 26

conc is greater than body fluids(skinny cell) 3% NaCl

Question 27

Active transport

Answer 27

use of energy to move solutes across the membrane going against the conc gradient

Question 28

Primary active transport

Answer 28

Energy used from ATP changes shape of transporter proteins, which pump substance across the membrane ex. Sodium ion/potassium pump

Question 29

Secondary active transport

Answer 29

the use of energy stored in hydrogen or sodium conc gradients that are used to drive other substances against their own conc gradients

Question 30

2 porters of 2nd active transport

Answer 30

antiporters(oposite directions), symporters(same direction)

Question 31

Endocytosis

Answer 31

material moving into a cell in a vesicle formed from the plasma membrane

Question 32

the 3 types of endocytosis are:

Answer 32

receptor-mediated endocytosis phagocytosis pinocytosis

Question 33

define receptor-mediated endocytosis

Answer 33

the selective taking of large molecules of viruses using receptors on the outer membrane - the reactors bind to solute then a vesicle shapes around it so it enters

Question 34

What is endocytosis?

Answer 34

The process by which cells internalize molecules by engulfing them in a vesicle.

Question 35

What is transcytosis?

Answer 35

* The transport of molecules across a cell, involving endocytosis on one side and exocytosis on the other.

Question 36

What is exocytosis?

Answer 36

Exocytosis is the process of vesicles fusing with the plasma membrane to release their contents outside the cell.

Question 37

What is receptor-mediated endocytosis?

Answer 37

Receptor-mediated endocytosis is a selective type of endocytosis where receptors on the cell surface bind to specific ligands for internalization.

Question 38

Differentiate between phagocytosis and pinocytosis.

Answer 38

Phagocytosis involves the engulfing of large particles or microorganisms, while pinocytosis involves the ingestion of extracellular fluid and dissolved substances.

Question 39

What is bulk-phase endocytosis?

Answer 39

Bulk-phase endocytosis is a non-specific form of pinocytosis where the cell takes in extracellular fluid.

Question 40

Define cytoplasm.

Answer 40

Cytoplasm is the region of the cell outside the nucleus containing organelles and cytosol.

Question 41

What is cytosol?

Answer 41

Cytosol is the fluid portion of the cytoplasm that surrounds the organelles.

Question 42

What are the three components of the cytoskeleton?

Answer 42

Microfilaments are actin filaments involved in movement and shape. Intermediate filaments provide mechanical support. Microtubules are involved in intracellular transport and cell division.

Question 43

What are cilia and flagella?

Answer 43

Cilia are short, hair-like structures for movement or fluid displacement. Flagella are long, whip-like structures for cell motility.

Question 44

What is the role of ribosomes?

Answer 44

Ribosomes are responsible for protein synthesis.

Question 45

What is the function of the endoplasmic reticulum (ER)?

Answer 45

The rough ER is involved in protein synthesis, while the smooth ER is involved in lipid synthesis and detoxification.

Question 46

What does the Golgi complex do?

Answer 46

The Golgi complex modifies, sorts, and packages proteins and lipids for secretion or delivery.

Question 47

What are lysosomes?

Answer 47

Lysosomes are organelles containing digestive enzymes for breaking down waste and cellular debris.

Question 48

What are peroxisomes?

Answer 48

Peroxisomes are organelles involved in breaking down fatty acids and detoxifying harmful substances.

Question 49

What are proteasomes?

Answer 49

Proteasomes are protein complexes that degrade unneeded or damaged proteins.

Question 50

What is the function of mitochondria?

Answer 50

Mitochondria generate ATP through cellular respiration.

Question 51

What are chromosomes?

Answer 51

Chromosomes are structures within the nucleus made of DNA and proteins, containing genetic information.

Question 52

Differentiate between transcription and translation.

Answer 52

Transcription is the process of synthesizing RNA from DNA. Translation is the process of synthesizing proteins from RNA.

Question 53

What is the difference between DNA and RNA?

Answer 53

DNA is double-stranded and stores genetic information, while RNA is single-stranded and used in protein synthesis.

Question 54

Differentiate between somatic and germ cells.

Answer 54

Somatic cells are body cells and are diploid. Germ cells are reproductive cells and are haploid.

Question 55

What is the difference between mitosis and meiosis?

Answer 55

Mitosis produces two identical diploid cells while meiosis produces four non-identical haploid gametes.

Question 56

What is cytokinesis?

Answer 56

Cytokinesis is the division of the cytoplasm, completing cell division.

Question 57

What is apoptosis?

Answer 57

Apoptosis is programmed cell death, a normal part of growth and maintenance.

Question 58

What is necrosis?

Answer 58

Necrosis is uncontrolled cell death due to injury or disease.

Question 59

Define haploid and diploid.

Answer 59

Haploid cells have one set of chromosomes (e.g., gametes), while diploid cells have two sets of chromosomes (e.g., somatic cells).

Question 60

What is atrophy, and how do cells respond to it?

Answer 60

Atrophy is a decrease in cell size, often as a response to reduced workload, malnutrition, or diminished blood supply.

Question 61

What is hypertrophy, and how do cells respond to it?

Answer 61

Hypertrophy is an increase in cell size, typically due to increased workload or stimulation, such as muscle growth from exercise.

Question 62

What is hyperplasia, and how do cells respond to it?

Answer 62

Hyperplasia is an increase in the number of cells, often as a response to hormonal stimulation or tissue regeneration.

Question 63

What is dysplasia, and how do cells respond to it?

Answer 63

Dysplasia is abnormal growth or development of cells, often associated with a precancerous condition or chronic irritation.

Question 64

What is metaplasia, and how do cells respond to it?

Answer 64

Metaplasia is a change from one cell type to another, often as an adaptive response to stress or environmental changes.

Question 65

How do cells respond to stress?

Answer 65

Atrophy is a decrease in cell size. Hypertrophy is an increase in cell size. Hyperplasia is an increase in cell number. Dysplasia is abnormal growth or development. Metaplasia is a change from one cell type to another.