1What is the first principle of cell theory?
All living organisms are composed of one or more cells
2What is the second principle of cell theory?
Cells are the smallest units of life
3What is the third principle of cell theory?
New cells come only from pre-existing cells by cell division
4Who proposed that all living things are made of cells?
Theodor Schwann and Matthias Schleiden
5Who stated that cells come from pre-existing cells?
Rudolf Virchow
6What are the two main categories of life?
Prokaryotes and eukaryotes
7What characterizes prokaryotic cells?
Simple structure and no nucleus
8Where is DNA located in prokaryotic cells?
In the nucleoid region
9What characterizes eukaryotic cells?
More complex structure with DNA enclosed in a membrane-bound nucleus
10What additional feature do eukaryotic cells have?
Internal membranes that form organelles
11What are organelles?
Membrane-bound compartments with specific structures and functions
12Why are eukaryotic cells described as compartmentalized?
Different functions occur in different organelles
13What is the nucleus?
The area where most genetic material is organized and expressed
14What is the nuclear envelope?
A double membrane that encloses the nucleus
15What are nuclear pores?
Passageways for molecules into and out of the nucleus
16What is chromatin?
A complex of DNA and proteins
17What is the nucleolus?
The site of ribosome subunit assembly
18What does the nucleolus lack that most organelles have?
A membrane
19What is the cytoplasm?
The region outside organelles but inside the plasma membrane
20What components make up the cytoplasm?
Cytosol, endomembrane system, and semiautonomous organelles
21What is the cytosol?
The fluid portion of the cell where many metabolic pathways occur
22What is the endomembrane system?
A network including nuclear envelope, ER, Golgi apparatus, lysosomes, plasma membrane
23How do endomembrane system components exchange materials?
Direct connections or vesicles
24What is the nuclear envelope continuous with?
The endoplasmic reticulum membrane
25What is the endoplasmic reticulum?
A network of membrane-bound tubules and flattened sacs
26What is the rough endoplasmic reticulum?
ER studded with ribosomes
27What is the function of rough ER?
Protein synthesis and sorting
28Why does rough ER look rough?
Because ribosomes are attached
29What is the smooth endoplasmic reticulum?
ER that lacks ribosomes
30What is the function of smooth ER?
Detoxification, lipid synthesis, carbohydrate metabolism, calcium balance
31What are ribosomes responsible for?
Protein synthesis
32What is the Golgi apparatus?
A stack of flattened membrane-bound compartments
33What are the three main functions of Golgi apparatus?
Protein processing, sorting, and secretion
34What does the Golgi apparatus package for export?
Proteins and carbohydrates
35What transports materials away from the Golgi?
Vesicles
36What are lysosomes?
Organelles containing hydrolytic enzymes (acid hydrolases)
37What is the function of lysosomes?
Break down proteins, carbohydrates, nucleic acids, and lipids
38Where are lysosomes formed?
From the ends of the Golgi apparatus
39Why are lysosomes called the suicide sac?
They can digest the cell if they rupture
40Which organelle digests phagocytosed food?
Lysosome
41What are semiautonomous organelles?
Organelles that grow and divide but depend on the cell
42Which organelles are semiautonomous?
Mitochondria and chloroplasts
43What is the primary function of mitochondria?
ATP synthesis
44What membranes do mitochondria have?
Outer and inner membrane
45What is the intermembrane space?
Space between the two mitochondrial membranes
46What is the mitochondrial matrix?
The inner compartment filled with gel-like fluid
47What are cristae?
Folds of the inner mitochondrial membrane that increase surface area
48How do mitochondria reproduce?
By binary fission
49From which parent are mitochondria inherited?
Mother
50What is the structure of a vacuole?
A fluid-filled membranous sac
51What is the main function of vacuoles?
Storage of enzymes and wastes
52How do vacuoles differ in plant vs animal cells?
Large in plant cells and small in animal cells
53What is the plasma membrane?
The boundary between the cell and the extracellular environment
54What does selectively permeable mean?
Controls what enters and exits the cell
55What is the basic structure of a cell membrane?
A phospholipid bilayer
56What model describes membrane structure?
The fluid mosaic model
57What does amphipathic mean?
Having both hydrophilic and hydrophobic regions
58Where are hydrophilic heads found in membranes?
Facing the aqueous environments
59Where are hydrophobic tails found in membranes?
Facing inward away from water
60What is embedded in membranes to allow transport?
Proteins
61What is diffusion?
Movement of molecules from high concentration to low concentration
62What is osmosis?
Movement of water across a partially permeable membrane from dilute to concentrated solution
63What is active transport?
Movement from low concentration to high concentration using energy
64What process moves CO₂ from cells into the blood?
Diffusion
65Which human cells contain flagella?
Sperm cells
66How many flagella does a sperm cell have?
One
67Which human cells contain cilia?
Ciliated epithelial cells
68How do cilia differ from flagella?
Cilia are short and multiple; flagella are long and single
69What is the function of cilia?
Move substances along the cell surface
70What characteristics do red blood cells lack?
A nucleus
71Why do red blood cells lack a nucleus?
To make more room for haemoglobin
72What is haemoglobin?
A red pigment containing iron that binds oxygen
73What is the function of red blood cells?
Transport oxygen and carbon dioxide
74What is the advantage of biconcave shape in red blood cells?
Increased surface area for faster diffusion
75Why is the red blood cell membrane flexible?
To squeeze through narrow capillaries
76What is the approximate size of a red blood cell?
7 µm
77What is cancer classified as (in this lecture)?
A genetic disease
78What causes cancer at the genetic level?
Mutations in genes controlling cell growth and function
79What cellular process fails in cancer cell division?
Apoptosis
80What is apoptosis?
Programmed cell death