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
