Curriculum
Login

Curriculum

Biology & Geology

Chapter 2 - Hormonal Coordination in Living Organisms

0/32

Chapter 3 - Reproduction in Living Organisms

0/33

Chapter 4 - Immunity in Living Organisms

0/34

Chapter 5 - Molecular Biology - DNA Structure and Function

0/43

Chapter 6 - Molecular Biology - RNA, Protein Synthesis and Genetic Engineering

0/38
Quiz

Lesson 3: Mechanism of the Immune System (Lines of Defense & Humoral/Cellular Immunity) — Lesson quiz

Submit quiz
Once you submit, you will no longer be able to change your answers. Are you sure you want to submit the quiz?
1.
Cytotoxic T-cells (TC) directly destroy virally infected cells and transplanted tissues by secreting:
Histamine and heparin
Perforin and lymphotoxins
Agglutinating antibodies
Thymosin and calcitonin
2.
Which of the following cellular changes occurs directly when a wilted plant shoot is irrigated with fresh water?
Lignin is immediately deposited inside the xylem vessel walls.
Cuticle thickness over leaf epidermis doubles within minutes.
Cell sap osmotic pressure increases and cell wall shrinks inward.
Water enters the vacuole via osmosis, expanding turgor pressure against the cell wall.
3.
During maximal skeletal muscle contraction according to Huxley's sliding filament model, which region experiences NO change in its absolute length?
The I-band (light isotropic zone)
The H-zone (central semi-light region)
The distance between two successive Z-lines
The A-band (dark anisotropic zone)
4.
What is the biochemical cause of continuous, non-relaxing muscle spasm that can cause muscular tearing?
Sudden accumulation of glucose inside glycogen granules.
Abrupt accumulation of excessive calcium ions in the synaptic cleft.
Complete depletion of cellular ATP molecules, preventing cross-bridge detachment.
Excessive breakdown of acetylcholine by the enzyme acetylcholinesterase.
5.
How many cervical vertebrae are present in the adult human vertebral column?
7 vertebrae
4 vertebrae
12 vertebrae
5 vertebrae
  • 1
  • 2
  • 3
  • 4
  • 5