SLP 1

Page 1: Introduction

  • Institution: Universiti Kebangsaan Malaysia

  • Document: Self-Learning Package on Cellular Biomolecules (CB-SLP-1)

  • Edition: Volume/Edition 2019

  • Target Audience: Medical Doctor (MD) Programme Students

  • Facilitator: Dr. Norwahidah Abdul Karim

Page 2: Learning Objectives

  • At the end of this topic, students should be able to:

    • Differentiate between prokaryotes and eukaryotes.

    • Describe the function of organelles and their inclusions.

    • Relate diseases associated with dysfunctions of these organelles.

  • References:

    1. Lieberman, M. & Marks, A. (2018). Basic Medical Biochemistry: A Clinical Approach. 5th Edition. Lippincott Williams & Wilkins.

    2. Baynes, J. & Dominiczak, M.H. (2018). Medical Biochemistry, 5th Edition. Elsevier Health Sciences.

    3. Murray, R.K. et al. (2018). Harper's Illustrated Biochemistry 31st Edition. Appleton & Lange.

    4. Ferrier, D.R. (2017). Lippincott's Illustrated Reviews. Biochemistry. 7th Edition. Lippincott Williams & Wilkins.

    5. Nussbaum, R.L. et al. (2015). Genetics in Medicine. 8th Edition. Elsevier Health Sciences.

    6. Online Resources:

      • http://journals.sfu.ca/paao/index.php/journal/article/viewFile/352/pdf

      • https://ghr.nlm.nih.gov/

  • Cellular Types:

    • Prokaryotic (e.g. bacteria) – no nucleus.

    • Eukaryotic (e.g. human cells) – contains a membrane-bound nucleus.

Page 3: Structure of Prokaryotic and Eukaryotic Cells

  • Prokaryotic Cell Structure:

    • Capsule, cell wall, plasma membrane.

    • Cytoplasm containing ribosomes, plasmids, and nucleoid (circular DNA).

  • Eukaryotic Cell Structure:

    • Cytoplasm enclosed by a plasma membrane.

    • Contains organelles such as centrioles, lysosomes, mitochondria, vacuoles, endoplasmic reticulum, nuclear envelope, and Golgi complex.

Page 4: Cell Membrane Overview

  • Cell/Plasma Membrane:

    • Encloses all human cells.

    • Composed of approximately 60% protein and 40% lipid.

    • Main lipid component: Phospholipid forming a bilayer due to hydrophilic and hydrophobic ends.

  • Functions:

    • Supports and retains cytoplasm.

    • Acts as a selective barrier for transport of nutrients and waste.

    • Allows selective transport of molecules; transport proteins often require energy.

    • Participates in cell communication and recognition.

Page 5: Organelles and Their Functions

  • Endoplasmic Reticulum (ER):

    • Two forms: Rough (with ribosomes) and Smooth (without ribosomes).

    • Functions: Mechanical support, synthesis of proteins and lipids, detoxification.

  • Golgi Complex:

    • Functions as a cellular post office: modifies, sorts, and packages proteins.

  • Lysosomes:

    • Contain digestive enzymes for cell maintenance and destroying damaged cells.

  • Peroxisomes:

    • Contain enzymes to break down peroxides; deficiencies lead to diseases like adrenoleukodystrophy.

Page 6: Mitochondrial Structure and Function

  • Mitochondria:

    • Have a double membrane: outer membrane and highly folded inner membrane (cristae).

    • Main function: ATP production (energy currency of the cell).

    • Contain their own DNA and ribosomes; possibly originated from ancient prokaryotic cells.

  • Ribosomes:

    • Composed of rRNA and protein; found in cytoplasm or on rough ER.

    • Main function: protein synthesis.

Page 7: Comparison Between Cell Types

  • Differences between Prokaryotes and Eukaryotes:

    • Key features such as nucleus presence, number of chromosomes, organelles, and cell structures.

  • Examples of Cellular Components:

    • Key structures defining prokaryotes and eukaryotes such as lysosomes, mitochondria, Golgi apparatus, etc.

Page 8: Protein Synthesis Processes

  • Ribosomes and Rough ER:

    • Ribosomes synthesize proteins; rough ER aids in their folding and modification.

    • Golgi apparatus modifies, sorts, and packages proteins for their cellular destinations.

  • Protein Pathways:

    • Various vesicle pathways exist, directing proteins to the membrane or lysosomes.

Page 9: Mitochondrial Function and Disease Association

  • Structure Suitable for ATP Production:

    • Discuss the adaptations of the mitochondrial structure that facilitate efficient ATP synthesis.

  • Diseases Linked to Organelles:

    • Various organelles such as mitochondria or peroxisomes related to specific diseases:

      • Zellweger syndrome

      • Leber's hereditary optic neuropathy

      • Von Gierke's disease

      • Tay-Sachs disease

      • I-cell disease.

  • Each listed condition can be further explored for its link to organelle dysfunction.