Topic 1 Cell Biology 1.1-1.3 Flashcards
1.1 What are the 3 points of cell theory?
1) Cells are the building blocks of structure in living things
2) They are the smallest unit of life
3) Cells are formed from other, pre-existing cells
1.1 What are the 4 common features of cells?
1) Surrounded by a membrane, separating its contents from everything outside
2) Contain genetic material needed for cell’s activities
3) Chemical reactions catalysed by enzymes produced in the cell
4) Has their own energy release system, powering the cell
1.1 Name the 3 exceptions to cell theory and why
1) Striated Muscle: made up of muscle fibres, very long >300mm with several hundred nuclei
2) Giant Algae: 100mm, feeds itself by photosynthesis
3) Fungi: many nuclei
1.1 State the 7 functions of life
Nutrition, response, metabolism, excretion, homeostasis, growth, reproduction
1.1 How do parameciums display the 7 functions of life? (Nutrition, response, metabolism, excretion, homeostasis, growth, reproduction)
1) Nutrition: cilia sweeps food into mouth, food vacuoles contain smaller organisms it consumed
2) Response: cilia helps cell move around
3) Metabolism: enzymes in cytoplasm catalyse metabolic reactions in cytoplasm
4) Excretion: waste products from metabolism eg.co2 are expelled through the plasma membrane
5) Homeostasis: contractile vacuoles fill up with water and expels through plasma membrane to manage water content in cell
6) Growth: ingests food, grows and divides
7) Reproduction: nucleus can divide to support cell division by mitosis but often asexual
1.1 What functions in a cell depend on its surface area and volume?
The rate of chemical reactions known collectively as metabolism is proportional to volume, rate of substances that move in and out of the cell depends on surface area.
1.1 If a cell grows larger/ smaller, the surface area to volume ratio becomes larger/ smaller?
Larger cell = smaller ratio
1.1 How to calculate image size?
Magnification times actual size
1.1 Explain cell differentiation (in context: how multicellular organisms develop specialised tissues) 2 marks
Group of cells specialising to form a tissue so they all perform the same function. Only some genes are expressed in the cell type/tissue therefore the tissues develop differently
1.1 Name a therapeutic use for stem cells, 4 marks.
Stem cells are useful in medical treatments due to their ability to differenciate (keyword when talking about stem cells). Can be derived from human embryos and some adult tissues. Can replace diseased or disfunctional cells.
Example: Stragardt’s Macular Dystrophy/ Stragardt’s Disease- causes photoreceptor cells to be degenerative so stem cells are injected into back of eyeball where they can develop into retina cells
1.2 Name all components in a liver cell
(Eukaryotic Animal Cell)
1) plasma membrane
2) 80S ribosomes
3) lysosome
4) rough endoplasmic reticulum (rough ER)
5) golgi apparatus
6) mitochondria
7) nucleus
1.2 Name all components in a E coli cell
(Prokaryotic Cell)
1) cell wall
2) plasma membrane
3) 70S ribosomes
4) plasmid
5) cytoplasm
6) pili
7) flagella
8) nucleoid
1.3 Components of cell membrane
1) phospholipid bilayers- phosphate head and lipid tail
2) integral proteins
3) peripheral proteins
4) glycoproteins
5) cholesterol
1.3 What properties do phospholipids have? Explain.
Partly hydrophobic, party hydophilic= amphipathic, phosphate head has negative charge therefore hydrophilic due to polarity, lipid tails have no charge and is repelled by water therefore it is inside
1.3 What is the use of cholesterol in the membrane?
Makes cell more stable and harder to break, keeps it fluid
1.3 Functions of integral proteins
Channels for passive transport, pumps for active transport, electron transport. Cell adhesion, immobilized enzymes.
1.3 Functions of peripheral proteins
Cell signal transmission from glycoproteins to nucleus
1.3 Functions of glycoproteins
Hormone binding sites, cell-to-cell communications/ cell recognition eg. receptors for neurotransmitters between two nerve cells
1.2 Describe the function of: plasma membrane
In which type of cell is it found?
Separate cell content from outside, control substance transfer
Found in both
1.2 Describe the function of: ribosomes (70S and 80S- which in which type of cell?)
Produce proteins- 70s in prokaryotes, 80s in eukaryotes
1.2 Describe the function of: lysosome
In which type of cell is it found?
Contains enzymes that breakdown waste, food etc.
Found in eukaryotic cells
1.2 Describe the function of: rough endoplasmic reticulum (rough ER)
In which type of cell is it found?
Synthesising proteins
Found in eukaryotic cells
1.2 Describe the function of: golgi apparatus
In which type of cell is it found?
Process/ package macromolecules, vesicle formation
Found in eukaryotic cells
1.2 Describe the function of: mitochondria
In which type of cell is it found?
Produce ATP
Found in eukaryotic cells
1.2 Describe the function of: nucleus
In which type of cell is it found?
Regulate cell activity, contains majority of DNA
Found in eukaryotic cells
1.2 Describe the function of: cell wall
In which type of cell is it found?
Prevent cell from bursting, holds shape
Found in prokaryotic cells and eukaryotic PLANT cells
1.2 Describe the function of: plasmid
In which type of cell is it found?
Naked DNA, extra genetic material, can make host resistant to antibiotics/ kill other types of bacteria/ digest unusual substances
Found in prokaryotic cells
1.2 Describe the function of: cytoplasm
In which type of cell is it found?
Contain enzymes that catalyse chemical reactions eg. metabolism
Found in prokaryotic cells
1.2 Describe the function of: pili
In which type of cell is it found?
Used for adhesion or transfer of genetic material
Found in prokaryotic cells
1.2 Describe the function of: flagella
In which type of cell is it found?
Locomotion/ movement
Found in prokaryotic cells
1.2 Describe the function of: nucleoid
In which type of cell is it found?
Primary DNA material, assist cell growth and development
Found in prokaryotic cells
