Lab 4 (chapter 4)

Question 1

What are the three major regions of a cell?

Answer 1

Plasma membrane, cytoplasm, and nucleus

Question 2

What are the main components of the plasma membrane?

Answer 2

Phospholipids, proteins, and carbohydrates attached to some of the lipids and proteins.

Question 3

What is selective permeability?

Answer 3

When some substances can pass through a membrane but not others

Question 4

Define primary active transport

Answer 4

A carrier protein moves the solute through a membrane up (against) its concentration gradient. This process requires ATP from the cell.

Question 5

Define passive transport

Answer 5

The movement of a molecule down its concentration gradient and across a membrane without the use of ATP

Question 6

Define simple diffusion

Answer 6

The net movement of particles from place of high concentration to place of lower concentration

Question 7

Define facilitated diffusion

Answer 7

A carrier protein moves the solute down its concentration gradient, and does not consume ATP

Question 8

What’s the difference between simple diffusion and facilitated diffusion?

Answer 8

Facilitated diffusion requires a carrier protein

Question 9

Define the nucleus

Answer 9

The “brain” of a cell

Question 10

Define the nuclear envelope

Answer 10

A double membrane with pores surrounding the nucleus

Question 11

Define nucleolus/ nucleoli

Answer 11

Masses where ribosomes are produced

Question 12

Define chromatin

Answer 12

A thread-like substance composed of DNA and protein; one of two substances that makes up nucleoplasm

Question 13

What’s the difference between cytoplasm and cytosol?

Answer 13

Cytoplasm contains the organelles; cytosol does not.

Question 14

What is included in the cytoplasm?

Answer 14

–Organelles
–Cytoskeleton
–Inclusions (stored or foreign particles)
–Cytosol (intracellular fluid, ICF)

Question 15

Define cytosol

Answer 15

The aqueous component of the cytoplasm of a cell

Question 16

Which organelle is best described as system of channels (cisternae) enclosed by a membrane?

Answer 16

The endoplasmic reticulum

Question 17

Which organelle is best described as parallel, flattened sacs covered with
ribosomes?

Answer 17

Rough ER

Question 18

What does the rough ER do?

Answer 18

Protein synthesis and packages proteins for transport

Question 19

What does the smooth ER do?

Answer 19

–Synthesizes steroids and other lipids
–Detoxifies alcohol and other drugs
–Calcium storage

Question 20

What do ribosomes do?

Answer 20

They “read” coded genetic messages
(messenger RNA) and assemble amino acids
into proteins specified by the code

Question 21

Which organelle is best described as small granules of protein and
RNA?

Answer 21

Ribosomes

Question 22

What does the golgi complex do?

Answer 22

•Receives newly synthesized proteins from
rough ER
•Sorts proteins, modifies proteins, and
packages them into vesicles
–Some vesicles become lysosomes
–Some vesicles migrate to plasma membrane and fuse to it
–Some become secretory vesicles that store a protein product for later release

Question 23

Which organelle is best described as an organelle

specialized for synthesizing ATP?

Answer 23

Mitochondria

Question 24

What do mitochondria do?

Answer 24

They make ATP

Question 25

What do centrioles do?

Answer 25

They form the mitotic spindle during cell division,

unpaired centrioles form basic structure of cilia and flagella

Question 26

Which organelle is best described as a package of enzymes bound by a membrane?

Answer 26

Lysosomes

Question 27

What do lysosomes do?

Answer 27

–Intracellular hydrolytic digestion
–Phagocytosis
–Autolysis

Question 28

What do peroxisomes do?

Answer 28

Detoxify certain harmful chemicals, enclose

reactions that make toxic byproducts

Question 29

What does the plasma membrane do?

Answer 29

•Defines cell boundaries
•Governs interactions with other cells
•Controls passage of materials in and out of
cell

Question 30

Which organelle would best be described as the border of the cell (arranged in bilayer)?

Answer 30

Plasma membrane