S1) Basic Cell Structure Flashcards Preview

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Flashcards in S1) Basic Cell Structure Deck (26)
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1
Q

State the structure and function of the following:

  • Nucleus
  • Nucleolus
  • Nuclear membrane
A
  • Nucleus – cell’s control centre, contains chromatin and DNA
  • Nucleolus – the region at the centre of the nucleus; role in ribosome production (stains dark)
  • Nuclear membrane – a two-layered selectively-permeable membrane with pores for passage of substances
2
Q

State the structure and function of the following:

  • Microtubules
  • Centriole
  • Microvillii
A
  • Microtubules – part of the cell’s cytoskeleton, aid movement of substances through cytoplasm
  • Centriole – composed of two cylinders of tubules; essential to cell reproduction
  • Microvilli – projections which increase the cell’s surface area
3
Q

State the structure and function of the following:

  • Microfilament
  • Vacuole
  • Cytoskeleton
A
  • Microfilament – provides support for the cell; sometimes linked to cell’s outer membrane
  • Vacuole – sac that stores and transport ingested materials, waste products and water
  • Cytoskeleton – internal framework of the cell, made up of microfilaments and hollow microtubules
4
Q

State the structure and function of the following:

  • Cytoplasm
  • Ribosome
  • Cell membrane
A
  • Cytoplasm –fluid in which organelles float; primarily water, contains enzymes and amino acids
  • Ribosome – tiny structure that assists with protein assembly
  • Cell membrane – encloses contents of the cell and maintains the cell’s shape; regulates passage of substances
5
Q

State the structure and function of the following:

  • Lysosome
  • sER
  • rER
A
  • Lysosome – produces hydrolytic enzymes that aid in digestion and excretion of substances
  • sER – network of tubes and flat curved sacs that helps to transport materials through the cell; main location of fat metabolism
  • rER – folded membranes studded with ribosomes, helps transport of materials through the cell; site of protein manufacture
6
Q

State the structure and function of the following:

  • Golgi complex
  • Mitochondrion
A
  • Golgi complex – a structure that processes and repackages proteins produced in the rER for release at the cell membrane
  • Mitochondrion – site of fat and sugar digestion in the cell (cellular respiration), produces energy
7
Q

What are the two types of chromatin?

A
  • Chromatin is found in two varieties: euchromatin and heterochromatin
  • Heterochromatin stains more intensely, indicating tighter packing
8
Q

What is limit of resolution?

A

Limit of resolution – the minimum distance at which two objects can be distinguished

9
Q

Outline the general structure of prokaryotic cells

A
  • Prokaryotic cells have an external membrane but no internal membranes
  • All the biochemical processes of the cell occur in the same compartment
10
Q

Identify 7 primary components of the prokaryotic cell

A
  • Capsule
  • Cell wall
  • Plasma membrane
  • Flagella
  • 70s Ribosomes
  • Nucleoid
  • Pili
11
Q

Outline the general structure of a eukaryotic cell

A
  • Eukaryotic cells are compartmentalised by internal membranes
  • Hence, eukaryotic cells have a true nucleus and true organelles
12
Q

Identify 10 primary components of the eukaryotic cell

A
  • Plasma membrane
  • Vacuole
  • Nuclear envelope
  • Nucleolus
  • Chromosomes
  • Lysosome
  • rER and sER
  • Golgi Complex
  • Free ribosomes
  • Mitochondria
13
Q

Describe the structure of plasma membranes

A
  • Composed of a phospholipid bilayer
  • Ampipathic
  • Associated membrane proteins: Integral and peripheral proteins
14
Q

Describe 5 functions of the plasma membrane

A
  • Selective permeability
  • Transport of materials along cell surface
  • Endocytosis and exocytosis
  • Intercellular recognition
  • Barrier to water-soluble molecules
15
Q

What is glycocalyx?

A
  • The glycocalyx is the cell coat
  • It is made up of oligosaccharide and polysaccharide side chains on the outside of the plasma membrane
16
Q

Outline 4 features of the Fluid Mosaic Model

A
  • Hydrophobic fatty acid tails in the middle
  • Hydrophilic heads on the outside
  • Membrane proteins: integral proteins, peripheral proteins
  • Phospholipids form a bi-layer
17
Q

Describe the structure of the endoplasmic reticulum

A
  • ER membrane is continuous and encloses a single lumen
  • sER does not have ribosomes attached
  • rER has ribosomes attached
18
Q

Distinguish between free and bound polyribosomes in terms of protein production

A
  • Free polyribosomes synthesise proteins which remain in the cytoplasm
  • Bound polyribosomes show protein synthesis and segregation into the rough ER
19
Q

Describe the role of the Golgi apparatus in the cell

A

The Golgi apparatus functions to modify, sort, concentrate and package proteins synthesised on the rough endoplasmic reticulum

20
Q

Outline the structure and function of lysosomes

A

- Structure: generated by the Golgi apparatus and contain many hydrolytic enzymes

  • Function: fuse with material requiring digestion
21
Q

Distinguish between primary and secondary lysosomes in terms of their formation and function

A
  • Primary lysosome:

I. Formed from the Golgi apparatus

II. Does not release intracellular contents

  • Secondary lysosome:

I. Formed by the fusion of the primary lysosome and an endocytotic/phagocytotic vesicle

II. Releases intracellular contents/waste products

22
Q

Describe the structure and function of mitochondria

A
  • Structure: double membrane, DNA, ribosomes and division similar to bacteria
  • Function: ATP generation by oxidative phosphorylation
23
Q

How are mitochondrias inherited?

A

Female lineage

24
Q

Identify 4 functions of the cytoskeleton

A
  • Determines the shape of animal cells
  • Ensures movement of cells
  • Structural support and movement of cell organelles
  • Provides the framework for moving and separating cells during cell division
25
Q

What are microtubules?

A

Microtubules are long hollow cylinders made of the protein tubulin

26
Q

Where are microtubules found?

A

Sites where structures are moved (i.e. nerve fibres, the mitotic spindle, cilia and flagella)