Name three characteristics of prokaryotic cells
- DNA is naked
- No nucleus
- Single chromosome
others can include: 70S ribosomes, usually not include introns
Name three characteristics of prokaryotic cells
- DNA is naked
- No nucleus
- Single chromosome
others can include: 70S ribosomes, usually not include introns, single chromosome (haploid)
Name three characteristics of eukaryotic cells
- DNA bound to protein
- Has a nucleus
- Organelles are membrane-bound
others can include: 80s ribosomes, usually has introns, chromosomes are paired (diploid)
What are the 7 functions of life in unicellular organisms?
- Metabolism → undertake essential chemical reactions
- Reproduction → produce offspring, either sexually or asexually
- Sensitivity/response → are responsive to internal and external stimuli
- Homeostasis → maintain a stable internal environment
- Excretion → exhibit the removal of waste products
- Nutrition → exchange materials and gases with the environment
- Growth → can move and change shape or size
What is the structure of a prokaryotic cell?
- Cell wall → composed of peptidoglycan; thicker than cell membrane
- Capsule → layer of carbohydrates that surround the cell wall (helps bacteria attach to other cells)
- Pilus/pili → thin rigid protein fibres on capsule (helps bacteria to other cells)
- Flagella → long tail like structure helps with movement
- Ribosomes → involved in protein synthesis
What is the structure of a eukaryotic cell?
Eukaryotic cells have a more complex compartmentalised structure. partitions are single or double membranes
benefits of this includes:
- enzymes and substrates can be more concentrated if they’re spread through cytoplasm
- substances that could cause damage can be contained
- conditions can be maintained at an ideal level for particular processes
- organelles with their contents can be moved around the cell
How do prokaryotic cells replicate?
Cell division. New cells can only be derived from pre-existing cells
Binary fission:
- plasmid (circular dna replicates itself and the 2 copies of chromosome move into opposite ends of the cell → cytoplasm then divides
each daughter cell contains one chromosome copy
All unicellular organisms are prokaryotes. True or False?
False.
Unicellular organisms are divided into two main types:
1. those with a nucleus (protists) eukaryotes
2. those without are nucleus (bacteria) are prokaryotes
What is the structure of a animal eukaryotic cell?
- Nucleus → membrane bound, contains linear DNA
- Mitochondria → double membrane, site of ATP synthesis
- Golgi body → move proteins
- Cytoplasm - jelly like substance holding organelles
- Ribosome → 80s, site of protein synthesis
- Endoplasmic reticulum (ER) - transports proteins
What is the structure of a plant eukaryotic cell?
In addition to the organelles in animal cells, plants also have:
- cell wall
- chloroplast
- large vacuole
- starch (stored as amyloplast of leucoplast)
What are the main differences between plant and animal cells?
- Cell walls are not present in animal but present in plant
- Chloroplasts are not present in animal but present in plant (photosynthesis)
- Carbohydrate storage animals (glycogen) in plants (starch)
- Vacuole frequent smaller in animals (although not usually present), in plants (singular large vacuole)
- Shape is rounder in animal (can change), in plants it is fixed and rigid
What does the nucleus contain?
- double nuclear membrane
- nuclear pores
- dense chromatic
- chromatin
What does the rough endoplasmic reticulum contain?
- ribosomes
- cisterna
What does the golgi apparatus contain?
- cisterna
- vesicles
What does the lyosome contain?
- digestive enzymes
- lyosome membrane
What does the mitochondrion contain?
- inner membrane
- outer membrane
- crista
- matrix
What does the chloroplast contain?
- starch grain
- stroma
- double membrane
- thylakoid
What is the difference between the vacuole and vesicles?
vesicles are smaller (usually found in animal cells) FACT CHECK THIS
What do the cilia and flagella contain?
- double microtubule
- plasma membrane
