Cytology Flashcards
Prokaryotic Cell
Small in structure
Reproduces identical offspring
No nucleus (DNA floating inside)
No membrane-bound internal cell structures
Seen in simple organisms eg. Bacteria
Has an additional cell wall
Has Pilli hairs
Eukaryotic Cell
Has Nucleus &
Organelles
Complex structure
Bigger in size
Reproduced through mitosis & miosis (can evolve)
Mitosis
somatic cell reproduction
Double amount of DNA in the mother cell (before the division)
1 division (46 on each side)
2 daughter cells
46 chromosomes
identical reproduction
Purpose: body cell growth & repair
Meiosis
Used to produce Gametes - Sex Cells
The outcome is to produce daughter cells with slightly different DNA. created genetically unique offsrping.
Process: Copy of cell 2 sets of 46 (each set is different )
1st division creates 2 cells with 46 chromosomes each
2nd division creates 4 unique cells with 23 chromosomes each (ready to pair with another sex cell to reform 46)
Basic Layers of the phospholipid bilayer
2 layers (outside + Inner side) of Phosphate heads - hydrophilic
Lipid tails facing inwards - hydrophobic
Hydrophilic
water-loving
Basic elements of the phospholipid bilayer
2 layers (outside + Inner side) of
Phosphate heads & Lipid tails
Transmembrane proteins (protein doorways)
Sugar & protein Chains -
Transmembrane (fat) - eg. Cholesterol.
Cell membrane sugar & protein chains role:
Act as flags to identify the cell as our own.
Protein chains act as receptors - eg. for hormones
Appear on outer phosphate heads
What do transmembrane proteins do
act as selective doorways letting things in and out of the cell.
Cholesterol role in the cell membrane
strength & reduces permeability
Nucleus
Holds DNA (6 ft) Hold Nucleolus
Nucleolus
holds RNA
mRNA purpose
mRNA - messenger to carry gene sequence from inside Nucleus DNA (Transcription) to Ribosomes (translation) for protein synthesis
MItochondria
Bean shapes structures
Form ATP (energy) in cells
Requires Glucose and oxygens to produce ATP
fuels metabolic processes within the cell
Ribosomes
the smallest structure within the cell
job is to make proteins
Endoplasmic Reticulum
Rough - contains ribosomes that make proteins to go OUTSIDE of the cell.
Smooth - no ribosomes - Produce Lipids & Steroid Hormones
Smoother Endoplasmic Reticulum
Smooth - no dots. Job is to make lipids & steroid hormones
Golgi Apparatus
Post office.
Enzymes package and send off proteins to outside the cell.
Lysosomes
Contains enzymes (up to 60). Job is to break things down within the cell (old organelles, waste material). Once broken down can be excreted from cell.
Cytoskeleton
Strains of protein found throughout the cell to give ot structure.
cytoplasm
water material within cell membrane
Transcription
mRNA takes a copy of section of DNA and takes it outside the nucleus to the Ribosome
Translation
The process of RNA being made into a protein within the ribosome
What is cytosol
Basic watery fluid inside a cell.
What is Cytoplasm
Cell content excludingthe nucleus (includes the cytosol and organelles).
What is phospholipid bilayer
Cell membrane
Phosphate heads are water
loving - hydrophilic
Lipid tails are water
hating - hydrophobic
Phospholipid bilayer contains
Phosphate heads & lipid tails
Transmembrane proteins
Transmembrane fats - Cholesterol
Microtubules
Proteins - strong & rigid.
Support structure of cell - scaffolding
maintain shape of cell.
Organelles travel through tubes to move inside the cell.
centrioles
Helps with Mitosis. Help pull the chromosomes to left and right before cell splits.
Types of Passive transport
Diffusion
Osmosis
Facilitated diffusion
Functions of Transmembrane proteins
Transport
Immunological ID
Receptors
Facilitated diffusion
the movement of larger substances from high to low concentration with the aid of transmembrane proteins.
Diffusion
the movement of small substances from a high to low concentration.
High to Low transport is
Passive Transport - NO energy
Low to High Transport is
Active Transport - requires energy
Types of Active Transport
- Pumps eg. Sodium / Potassium Pump
- Endocytosis
- Exocytosis
Endocytosis
Engulfing of particles into the cell membrane wall
Exocytosis
Removal of waste from cell