chapter 3, cell form and function

Question 1

What is a cell?

Answer 1

The basic structural and functional unit of life.

Question 2

What is the plasma membrane?

Answer 2

The outer boundary of the cell, composed of a phospholipid bilayer.

Question 3

What is cytoplasm?

Answer 3

The fluid-filled interior of the cell, containing organelles.

Question 4

What is cytosol?

Answer 4

The fluid portion of the cytoplasm.

Question 5

What is extracellular fluid (ECF)?

Answer 5

Fluid outside of the cell.

Question 6

Define phospholipid bilayer.

Answer 6

A double layer of phospholipids forming the membrane.

Question 7

What is a hydrophilic head?

Answer 7

Water-loving part of a phospholipid.

Question 8

What is a hydrophobic tail?

Answer 8

Water-repelling part of a phospholipid.

Question 9

What role does cholesterol play in the plasma membrane?

Answer 9

A lipid that stabilizes the membrane.

Question 10

What are integral (transmembrane) proteins?

Answer 10

Proteins that span the entire membrane.

Question 11

What are peripheral proteins?

Answer 11

Proteins attached to one side of the membrane.

Question 12

What is glycocalyx?

Answer 12

A carbohydrate coat on the cell surface that functions in cell recognition.

Question 13

Define selective permeability.

Answer 13

The ability of the membrane to regulate what enters and exits.

Question 14

What is passive transport?

Answer 14

Movement of substances without energy.

Question 15

What is diffusion?

Answer 15

Movement of molecules from high to low concentration.

Question 16

What is osmosis?

Answer 16

Diffusion of water across a membrane.

Question 17

What is facilitated diffusion?

Answer 17

Movement of molecules using a transport protein.

Question 18

What is active transport?

Answer 18

Movement of substances against a gradient, requiring ATP.

Question 19

Define primary active transport.

Answer 19

Uses ATP directly (e.g., sodium-potassium pump).

Question 20

What is secondary active transport?

Answer 20

Uses energy from another molecule’s transport.

Question 21

What is endocytosis?

Answer 21

The process of engulfing substances into a cell.

Question 22

What is phagocytosis?

Answer 22

‘Cell eating,’ engulfing large particles.

Question 23

What is pinocytosis?

Answer 23

‘Cell drinking,’ engulfing extracellular fluid.

Question 24

What is receptor-mediated endocytosis?

Answer 24

Selective uptake using receptor proteins.

Question 25

What is exocytosis?

Answer 25

Process of vesicles fusing with the plasma membrane to release substances.

Question 26

What is the nucleus?

Answer 26

The control center of the cell, containing DNA.

Question 27

What is the nuclear envelope?

Answer 27

A double membrane surrounding the nucleus.

Question 28

What are nuclear pores?

Answer 28

Openings allowing material to move in and out of the nucleus.

Question 29

What is the nucleolus?

Answer 29

Site of ribosome synthesis.

Question 30

What are ribosomes?

Answer 30

Sites of protein synthesis.

Question 31

What is the endoplasmic reticulum (ER)?

Answer 31

A network of membranes involved in protein and lipid synthesis.

Question 32

What is rough ER?

Answer 32

Studded with ribosomes; synthesizes proteins.

Question 33

What is smooth ER?

Answer 33

Lacks ribosomes; synthesizes lipids and detoxifies substances.

Question 34

What is the Golgi apparatus?

Answer 34

Modifies, packages, and ships proteins and lipids.

Question 35

What are lysosomes?

Answer 35

Contain digestive enzymes for breaking down waste and cellular debris.

Question 36

What are peroxisomes?

Answer 36

Contain enzymes that neutralize toxins and break down fatty acids.

Question 37

What are mitochondria?

Answer 37

The powerhouse of the cell; produces ATP via cellular respiration.

Question 38

What is the cytoskeleton?

Answer 38

A network of protein filaments providing structure and movement.

Question 39

What are microfilaments?

Answer 39

Thin filaments involved in cell movement and shape.

Question 40

What are intermediate filaments?

Answer 40

Provide structural support.

Question 41

What are microtubules?

Answer 41

Form the spindle apparatus and help with intracellular transport.

Question 42

What are centrioles?

Answer 42

Organize microtubules and play a role in cell division.

Question 43

What are cilia?

Answer 43

Hair-like structures that move substances along the cell surface.

Question 44

What are flagella?

Answer 44

Long, whip-like structures used for cell movement (e.g., sperm).

Question 45

What is the cell cycle?

Answer 45

The life cycle of a cell, including growth and division.

Question 46

What is interphase?

Answer 46

The period of cell growth and DNA replication.

Question 47

What occurs during the G1 phase?

Answer 47

Cell grows and prepares for DNA replication.

Question 48

What occurs during the S phase?

Answer 48

DNA replication occurs.

Question 49

What occurs during the G2 phase?

Answer 49

Cell prepares for division.

Question 50

What is mitosis?

Answer 50

The division of the nucleus into two identical daughter cells.

Question 51

What happens during prophase?

Answer 51

Chromosomes condense, spindle fibers form.

Question 52

What happens during metaphase?

Answer 52

Chromosomes align at the cell equator.

Question 53

What happens during anaphase?

Answer 53

Sister chromatids separate.

Question 54

What happens during telophase?

Answer 54

Nuclear envelope reforms, chromosomes uncoil.

Question 55

What is cytokinesis?

Answer 55

Division of the cytoplasm, forming two separate cells.

Question 56

What is apoptosis?

Answer 56

Programmed cell death.

Question 57

What is DNA?

Answer 57

The molecule that stores genetic information.

Question 58

What is RNA?

Answer 58

Transfers genetic instructions for protein synthesis.

Question 59

What is a gene?

Answer 59

A segment of DNA coding for a specific protein.

Question 60

What is transcription?

Answer 60

The process of copying DNA into mRNA.

Question 61

What is translation?

Answer 61

The process of converting mRNA into a protein.

Question 62

What is mRNA?

Answer 62

Carries genetic information from DNA to ribosomes.

Question 63

What is tRNA?

Answer 63

Transfers amino acids to ribosomes during protein synthesis.

Question 64

What is rRNA?

Answer 64

A structural component of ribosomes.

Question 65

What is a codon?

Answer 65

A sequence of three nucleotides that codes for an amino acid.

Question 66

What is an anticodon?

Answer 66

The complementary sequence on tRNA that pairs with a codon.