From CellBiology

Individual Online Project

My Lecture Summary

My Lecture 2 Notes-Cells Eukaryotes and Prokaryotes

  • In this lecture, i will need to identify differences between prokaryotes and eukaryotes. i will also need to identify the differences between unicellular and multicellular organisms. Understand biological molecules, dimensions of cells, virus and prions.
  • Differences between prokaryotes and eukaryotes: prokaryotes do not have nucleus, but eukaryotes do. prokaryotes do not possess cellular compartments, whereas eukaryotes do. The diameter of a prokaryote cell is smaller than a eukaryote cell. prokaryotes do not have cytoskeleton. prokaryotes do not have cytoplasmic organelles. prokaryotes have single circular DNA molecule. eukaryotes have multiple linear DNA molecules.
  • Differences between unicellular and multicellular: unicellular organisms are prokaryotes, and includes some eukaryotes. multicellular organisms contain eukaryotes, plants, animals, and function, tissues.
  • virus: not alive, does not belong to cell and unable to grow or reproduce outside of a host cell.
  • Prion: not a living cell, an infectious prion protein. Diseases caused by prion, such as CJD and BSE mad cow disease.

My Lecture 3 Notes-Cell Membranes and Compartments

  • I will need to be able to identify structure of membranes. I will need to understand the difference between physical and functional compartments.
  • membrane bound compartments such as nucleus, cytoplasm.
  • functional compartments include spatial localization, targeting, activation and inactivation and signaling.
  • volume occupied by the cytoplasmic organelles within a cell. eg, cytosol 54%, mitochondria, 22%, rough ER 9%, smooth ER 6% and nucleus 6%.
  • Types of organelles such as nucleus, rough ER, smooth ER, mitochondria, golgi apparatus...
  • Membrane functions. eg, form compartments, cell identity, detection of signals, regulation of transport...
  • membrane contains phospholipids, glycolipids and steriods.
  • mebrand protein functions.

Lecture Homework

Lecture 4-Nucleus

There are a number of issues that i found interesting in lecture 4.

Functional components of nucleus such as Cajal bodies and PML bodies.

  • Cajal bodies:
 >proposed sites where small nuclear ribonuclearporteins and small nuclear RNA are modified
  • PML bodies:
 >promyelocytic leukaemia nuclear bodies
 >involved in viral infection, cellular transformaion, innate immunity, growth control and apoptsis
  • As well as histones:
 >only in eukaryotes

Lecture 5-Homework

What i found difficult to understand is the concept of association of different cellular components with exocytosis. How do their functions and structures facilitate the process of exocytosis. There are four cellular components that associate with exocytosis process. They are ribosome, endoplasmic reticulum, transport vesicles and golgi apparatus. And their major functions involved in proteins synthesis, protein modification, lipid metabolism, dextocification of harmful substances, transport to golgi apparatus. And i understand their structures. But how are these relate to exocytosis?

Lecture 7-Homework

Q: what types of cellular process within a cell require energy?

A: Cellular processes such as active transport and reverse osmosis require energy input.

  • Active transport is the movement of molecules up their concentration gradient, using energy;
  • Reverse osmosis is used to drive solvent out of a solution by forcing it through a semi-permeable membrane by increasing the pressure on the high concentration side. This requires energy.

Redo Lecture 7-Homework

Q: What types of cellular processes require lots of energy from mitochondria?

A: Cellular respiration and Electron transport chain.

P.S. i need help with this one, Dr. Hill

Lecture 8-Homework

Q:What do the acronyms (N-CAM)N-CAM, Ng-CAM L-CAM, I-CAM mean?

N-CAM: neural cell adhesion molecule

L-CAM: liver cell adhesion molecule. It appears on non-neural epithelial tissues and it mediates calcium-dependent adhesion in the tissues located in the embryo and adult;

I-CAM: Intercellular adhesion molecule. They are members of the family of cell adhesion molecules and CAMS are proteins located on the cell surface involved with the binding with other cells or with extracellular matrix;

Ng-CAM: Neuron-glia cell adhesion molecule. It is a type of adhesion molecule that associates in binding between the neurons and between neuron and glia.

Lecture 10-Homework

Q:What is the name of the epidermal layer between the basal and granulosa layer and how does it relate to intermediate filaments?

A: Stratum spinosum The epidermis contains five layers. From deep to superficial the layers are named in following order: 1.stratum basale 2.stratum spinosum 3.stratum granulosum 4.stratum licidum 5.stratum corneum

Intermediate filaments have great tensile strength, and their main function is to enable cells to withstand the mechanical stress that occurs when cells are stretched. The intermediate filaments in each cell are indirectly connected to those of neighboring cells through the desmosomes, establishing a continuous mechanical link from cell to cell throughout the tissue.

As a result desmosomes are located in stratum spinosum.

Lab 6-Homework

Q: Describe the differences in the distribution of phenotypes in Tm4 over-expressing B35 cells versus control B35 cells. Formulate a hypothesis with regard to what changes on the molecular level may have occurred due to the over-expression of Tm4 that lead to morphological changes that you have observed.

A: experimental results:

Tm4 total no:174 A-"Fan": 5 B-"Broken fan": 29 C-"Stumped": 4 D-"Pronged": 57 E-"Stringed" 75 F-"Pygnotic": 4

WT total no: 94 A-"Fan": 2 B-"Broken fan": 44 C-"Stumped": 0 D-"Pronged": 13 E-"Stringed": 29 F-"Pygnotic": 6

Majority of the phenotypes have been observed, however, my results are inconclusive. Figures tend to favour "Pronged" and "Sringed" type Both genotype A and genotype B share similar morphology. The cells were mainly "Pronged" and "Stringed" Genotype A

  • demonstrates higher concentration of cell numbers, primarily Stringed
  • cells tend to be shorter

Genotype B

  • will most likely demonstrates higher number of "Pronged" type
  • cells tend to be taller

Conclusion: results indicates that Tm4 mutant cells compared to the wild type (WT) B35 cells, both cell morphology and nutrites have been changed. As a result, showing tryptomyosin specificity are being located to suit different role.

Lecture 14-Homework

Q: What are the 2 main forms of generating confocal microscopy?

A: There are two main forms of generating confocal microscopy such as spinning disc method and laser light method.

Lecture 15-Homework

Q: What is S phase abbreviated for?

A; S phase is abbreviated for Synthesis phase. As part of cell cycle, DNA synthesis and replication occurs in this phase. S phase is part of the interphase, which is happens between G1 and G2 subphase. At the start of s phase, each chromosome is composed of one coiled DNA double helix molecule, which is known as chromotid. The enzyme DNA helicase splits the DNA double helix down the hydrogen bonds. Then DNA polymerase follows, attaching a complementary base pair to the DNA strand, making two new semiconservative strands. At the end of S phase, each chromosome has two identical DNA double helix molecules, therefore two sister chromotids have formed.