What makes up a cell?
Nucleus, Cytoplasm, Plasma membrane
What is the function and structure of the nucleus?
functions:
control centre of the cell - controls protein synthesis
contains DNA - genetic material, blueprint for the activity of all cells
structure:
surrounded by nuclear envelope - nuclear pores allow movement of molecules in and out of the nucleus
What is the nuclear envelope?
double layered membrane that separates the nucleus from the rest of the cell
Ribosomes role and types
needed for protein synthesis
types: free ribosomes and membrane-bound ribosomes
Difference between free ribosomes and membrane-bound ribosomes
free ribosomes are suspended in cytosol (cell solution) and make proteins that mostly function in the cytosol whereas membrane-bound ribosomes are bound to endoplasmic reticulum and creates proteins that mostly function in membrane or outside of the cell
What does cytoplasm consist of?
- Organelles “cellular organs” that are mostly surrounded by a membrane
- Cytosol - a jelly like fluid
- Inclusions - chemical substances e.g. pigments, stored nutrients
What are the types of cytoplasm organelles?
- endoplasmic reticulum
- golgi apparatus
- lysosomes
- peroxisomes
- mitochondria
What is the Endoplasmic Reticulum and its types?
the ER is an extensive network of membranes joining the nucleus
two types: rough ER and smooth ER
Rough Endoplasmic Reticulum
- is attached to the nucleus
- is covered in rough ribosomes
- makes proteins
- acts as a membrane factory by packaging and transporting proteins to the Golgi Apparatus in transport vesicles
Smooth Endoplasmic Reticulum
- has specialised functions in particular cells
e.g. detoxification (liver and kidneys)
making steroid-based hormones (testes)
releasing calcium for muscle contraction (skeletal and cardiac muscle)
Golgi Apparatus function
- is a series of curved sacs
- accepts transport vesicles form the ER for further processing like a post office
- proteins are modified, sorted and shipped to their final destination such as outside the cell, to the various membranes, to the organelles
Lysosomes and Peroxisomes
Membrane bound vesicles containing enzymes that bud off from the ER or golgi apparatus
Lysosomes - break down organic material inside the cell e.g bacteria
Peroxisomes - degrade toxic molecules inside the cell
What are enzymes?
Molecules that speed up chemical reactions without being consumed by the reaction
- catalyst
- made up of proteins
What are the 4 main tissue types and where are they?
- Epithelia (external surface of the body, lining internal surfaces, glands)
- Connective tissue (Bones, Cartilage, tendons, ligaments, adipose (fat) tissue, blood)
- Muscle (cardiac muscle - involuntary,
skeletal muscle - voluntary, smooth muscle - involuntary)
Muscles are important for stabilizing and controlling our organs and movement. - Neural tissue (neurons, glia (neuroglia))
Important for control and cell communication to your muscles
Medial and Lateral
Superior and Inferior
Proximal and distal
Medial - towards midline of the body
Lateral - further from the midline of the body
Superior - towards your head
Inferior - towards the ground
Proximal - closer to the attachment of the limb
Distal - further away to the attachment of the limb
Anterior (ventral) and Posterior (dorsal)
Superficial and Deep
Anterior - towards front of the body
Posterior - towards back of the body
Superficial - closer to the skin
Deep - deeper inside the body than the skin
Sagittal Plane
Divides body into left and right
The midline is the median/midsagittal plane
Frontal (coronal) Plane
Divides body into front and back (anterior and posterior)
Transverse (horizontal) plane
Divides the body into superior and inferior (top and bottom)
- A transverse section is often called a cross section
Explain the role of ribosomes in the production of proteins
Mitochondria
Power plant of the cell
- important for producing energy (ATP)
Carries out aerobic cellular respiration
- nutrients in food converted to CO2 and H2O
- released energy is stored as ATP
basically energy in presence of oxygen - take nutrients from our food and as a result releases waste and water (CO2 and H2O)
ATP
Adenosine Triphosphate
- the chemical bond between the last two phosphate groups is broken
- energy is released when terminal phosphate group is removed
