Mod 2.1

Question 1

What are the three main components of a human cell?

Answer 1

Plasma membrane, cytoplasm, and nucleus.

Question 2

What are the two parts of cytoplasm?

Answer 2

Cytosol (fluid portion) and organelles (membrane-bound structures).

Question 3

What is the function of the nucleus?

Answer 3

Contains DNA and regulates gene expression and cell activities.

Question 4

What structure synthesises proteins?

Answer 4

Ribosomes — non-membranous structures that assemble polypeptides from mRNA.

Question 5

What organelle modifies and packages proteins for secretion?

Answer 5

Golgi complex (Golgi apparatus).

Question 6

What organelle digests worn-out organelles and cellular debris?

Answer 6

Lysosome.

Question 7

What organelle detoxifies harmful substances like alcohol?

Answer 7

Peroxisome.

Question 8

What is the function of the rough endoplasmic reticulum (RER)?

Answer 8

Processes and transports proteins synthesised by attached ribosomes.

Question 9

What is the function of the smooth endoplasmic reticulum (SER)?

Answer 9

Synthesises lipids and steroids; detoxifies drugs and poisons.

Question 10

What is the function of the centrosome?

Answer 10

Organises microtubules; forms spindle fibres during mitosis.

Question 11

What are the four basic tissue types in the human body?

Answer 11

Epithelial, connective, muscle, and nervous tissue.

Question 12

What are the four major functions of epithelial tissue?

Answer 12

Protection, secretion, absorption, and filtration/transport.

Question 13

What are the main characteristics of epithelial tissue?

Answer 13

Polarity, basement membrane attachment, avascularity, high regenerative capacity.

Question 14

What does “avascular” mean in epithelial tissue?

Answer 14

Lacks its own blood supply; nutrients diffuse from nearby tissues.

Question 15

What are the three basic epithelial cell shapes?

Answer 15

Squamous (flat), cuboidal (cube-shaped), columnar (tall).

Question 16

What are the three types of epithelial layering?

Answer 16

Simple (one layer), Stratified (multiple layers), Pseudostratified (appears layered, all cells touch basement membrane).

Question 17

Where is simple squamous epithelium found?

Answer 17

Lining alveoli of lungs, blood vessels, and serous membranes — allows diffusion and filtration.

Question 18

What is the function of simple cuboidal epithelium and where is it found?

Answer 18

Secretion and absorption; found in kidney tubules and glandular ducts.

Question 19

What is the function of simple columnar epithelium in the GI tract?

Answer 19

Absorption (with villi) and secretion (goblet cells); lacks cilia.

Question 20

What are the features of pseudostratified columnar epithelium in the trachea?

Answer 20

Ciliated, with goblet cells; functions in mucus secretion and transport.

Question 21

What is the role of stratified squamous epithelium?

Answer 21

Protection; keratinised type in skin, non-keratinised in mouth, esophagus, vagina.

Question 22

Where is stratified cuboidal epithelium found?

Answer 22

Sweat and salivary glands; provides protection and limited secretion/absorption.

Question 23

Where is stratified columnar epithelium found and what is its function?

Answer 23

Conjunctiva, parts of urethra and pharynx; provides protection and secretion.

Question 24

What is transitional epithelium and where is it found?

Answer 24

Found in bladder and ureters; cells change shape based on stretching (dome-shaped when relaxed, flat when stretched).

Question 25

What is the function of goblet cells?

Answer 25

Secrete mucus to protect and lubricate epithelial surfaces.

Question 26

What are mucous membranes and where are they located?

Answer 26

Epithelial linings of body cavities open to the exterior — respiratory, digestive, and urogenital tracts.

Question 27

What are cell junctions?

Answer 27

Structures that connect adjacent cells to maintain tissue integrity and communication.

Question 28

Which tissues commonly contain cell junctions?

Answer 28

Epithelial, cardiac muscle, smooth muscle, and nervous tissues.

Question 29

What is the function of tight junctions?

Answer 29

Create a watertight seal to prevent leakage between cells (e.g., intestines, bladder).

Question 30

What is the function of adherens junctions?

Answer 30

Use actin filaments to help cells resist separation during stretching (like in intestines).

Question 31

What is the function of desmosomes?

Answer 31

Provide strong anchoring between cells; found in skin and cardiac muscle.

Question 32

What is the function of hemidesmosomes?

Answer 32

Anchor epithelial cells to the basement membrane (not to other cells).

Question 33

What is the function of gap junctions?

Answer 33

Allow small molecules and ions to pass between cells; enable intercellular communication (e.g., cardiac muscle).

Question 34

What is the key difference between endocrine and exocrine glands?

Answer 34

Endocrine glands release hormones into the bloodstream; exocrine glands release substances into ducts.

Question 35

What are the three types of exocrine secretion and examples?

Answer 35

Merocrine (e.g., salivary glands), Apocrine (e.g., mammary glands), Holocrine (e.g., sebaceous glands).

Question 36

What are the main functions of connective tissue?

Answer 36

Support, bind, protect, insulate, store energy, and transport.

Question 37

What are the two main components of connective tissue?

Answer 37

Cells and extracellular matrix (ECM).

Question 38

What is ground substance?

Answer 38

The gel-like material in ECM between fibres and cells; contains water, proteins, and polysaccharides.

Question 39

What are the three major protein fibres in CT?

Answer 39

Collagen (strength), elastic fibres (stretch), and reticular fibres (support).

Question 40

What are the types of solid connective tissue?

Answer 40

Loose CT (areolar, adipose, reticular), dense CT (regular, irregular, elastic), cartilage (hyaline, fibrocartilage, elastic), bone.

Question 41

What are the types of liquid connective tissue?

Answer 41

Blood and lymph.

Question 42

What are the three types of muscle tissue?

Answer 42

Skeletal (striated, voluntary), Cardiac (striated, involuntary), Smooth (non-striated, involuntary).

Question 43

Which muscle tissue pumps blood throughout the body?

Answer 43

Cardiac muscle.

Question 44

What are the two major cell types in nervous tissue?

Answer 44

Neurons and neuroglia.

Question 45

What is the function of neurons?

Answer 45

Receive stimuli and transmit electrical signals throughout the body.

Question 46

What is the role of neuroglia?

Answer 46

Support, nourish, and protect neurons; regulate the neural environment; form myelin.