B2.1 Cell structure

What organisms are included in Prokaryotes?⁠

Bacteria and Archaea.

What 4 kingdoms belong to Eukaryotes?

Plant, animal, fungi, and protist (protoctista)

What is the definition of a Prokaryote?

An organism whose DNA is suspended freely in the cytoplasm without a nucleus ('before nucleus').

What are the main features of Prokaryotic (bacteria) cell structure?⁠

⁠No nucleus (only a loop of circular DNA), no mitochondria, no chloroplasts, and cell wall made of peptidoglycan (not cellulose).⁠

What is the function of Plasmids in bacteria?⁠

⁠Small loops of DNA that carry drug resistance genes and are used in genetic engineering.⁠

What is the function of Capsule and Flagellum in bacteria?⁠

Capsule: protects against drying out. Flagellum: used for movement.⁠

What is the definition of a Eukaryote?⁠

An organism containing DNA inside a membrane-bound nucleus, separate from the cytoplasm.⁠

What 3 features do animal and plant cells have in common?⁠

1. Cytoplasm 2. DNA 3. Cell membrane.⁠

What is the function of the Cell Membrane (plasma membrane)?⁠

• Controls and regulates the passagesof substances in and out of the cell

• holds the cell together.⁠

What is the function of the Nucleus?

• Contains genetic material (DNA) in chromosomes

• controls cell growth, work, and cell division.⁠

What is the function of Cytoplasm?⁠

• Site where all metabolic/chemical reactions take place

• supports cell structures.

What is the function of Mitochondria?⁠

• Site of aerobic respiration, providing energy for the cell ('powerhouse').⁠

• not found in prokaryotes

What is the function of Ribosomes?⁠

• Site for protein synthesis.⁠

What is the function of the Vacuole?

• Temporary storage space for cell sap (sugars/solutions)

• helps support cell shape (plants have 1 large vacuole/animal cells many small ).⁠

What is the function of the Cell Wall ?

• Made of cellulose

• provides extra support and defines shape

• fully permeable.⁠

What is the function of Chloroplasts?⁠

• Contains chlorophyll to absorb sunlight

• site of photosynthesis