Chapter 4

Question 1

Cells

Answer 1

are extremely diverse
require microscope to be seen
each type in our body is specialized for a particular function

Question 2

Why are cells so small?

Answer 2

need surface areas large enough to enter and exit out of materials
small cells have more surface area for exchange

Question 3

Plasma membrane

Answer 3

marks boundary between outside and inside of a cell
selectively permeable - selectively chooses what can go in and out of a cell
phospholipid bilayer with embedded proteins
polar molecules (CO2 and Oxygen) get in, non polar molecules and large molecules do not get in (NaCl and sugar)

Question 4

Channel proteins

Answer 4

form tunnel for specific molecules
acts as a gate which can open and close
specific for each ion, one at a time

Question 5

Transport proteins

Answer 5

involved in passage of molecules through membrane, sometimes requiring input of energy
moving ions from 1 side to another

Question 6

Cell recognition proteins

Answer 6

glycoproteins
enable our body to distinguish between our own cells of other organisms

Question 7

Receptor Proteins

Answer 7

allow signal molecules to bind, causing a cellular response
ligand - molecule that binds to a receptor

Question 8

enzymatic proteins

Answer 8

directly participate in metabolic reactions
speed up chemical reactions

Question 9

junction proteins

Answer 9

link/attach cells to one another
cell-cell adhesion and communication

Question 10

Cell theory

Answer 10

all organisms are composed of cells
all cells come only from preexisting cells

Question 11

all cells have…

Answer 11

plasma membrane to regulate movement or material
cytoplasm where chemical reactions occur
genetic material for growth and reproduction

Question 12

2 main types of cells

Answer 12

prokaryotic - lack membrane-bound nucleus
eukaryotic - have nucleus housing DNA

Question 13

Prokaryotic Cells

Answer 13

organisms from domain Bacteria and Archaea
generally smaller and simpler in structure than eukaryotic cells
- allows them to reproduce very quickly and effectively
extremely successful group of organisms

Question 14

bacteria

Answer 14

some can cause disease
others have roles in the environment
some are used to manufacture chemicals, food, drugs, etc.

Question 15

Bacterial structure

Answer 15

cytoplasm surrounded by plasma membrane and cell wall
cell wall maintains the shape of a well
Dna (in nucleoid) Ribosomes (site of protein synthesis)
appendages - Flagella (propulsion), Fimbriae (attachment to surfaces), Conjugation pill (DNA transfer)

Question 16

Eukaryotic cells

Answer 16

protists, fungi, plants, animals
have membrane bounded nucleus housing DNA
much larger than prokaryotic cells
compartmentalized and contain organelles

Question 17

four categories of organelles

Answer 17

nucleus and ribosomes
endo membrane system
energy-related
cytoskelton

Question 18

Nucleus

Answer 18

stores genetic information
has chromatin, nucleus, DNA, and nuclear envelope

Question 19

Chromatin

Answer 19

diffuse DNA, protein, some RNA

Question 20

Nucleolus

Answer 20

region where ribosomal RNA is made

Question 21

Nuclear Envelope

Answer 21

double membrane, nuclear pores permit passage in and out

Question 22

Ribosomes

Answer 22

carry out protein synthesis in the cytoplasm
found in both prokaryotes and eukaryotes
composed of 2 subunits
mix of proteins and ribosomal RNA
receive mRNA as instructions sequence of amino acids in polypeptide

Question 23

Endomembrane System

Answer 23

consists of nuclear envelope, membranes of endoplasmic reticulum, Golgi apparatus, and numerous vesicles
helps compartmentalize cell
transport vesicles carry molecules from one part of the system to another

Question 24

Endoplasmic reticulum

Answer 24

complicated system of membranous channels
physically continuous with outer membrane of nuclear envelope
Rough vs Smooth ER

Question 25

Rough ER

Answer 25

studded with ribosomes
modifies proteins in lumen
forms transport vesicles going to Golgi apparatus