Cell Specialisation Flashcards
What is cell theory
- All known living things are made up from one or more cells
- The cell is the fundamental unit of structure and function in all living organisms
- All living cells arise from from pre-existing cells through cell division
- Cells contain DNA and RNA, where DNA is passed between cells during cell division
- Energy transfer occurs within cells
- All cells have the same basic composition
Describe what is meant by unicellular
Made from one cell
Describe what is meant by multicellular
Made from many cells
Are prokaryotes unicellular or multicellular
Usually unicellular
What is the difference between eukaryotes and prokaryotes
Prokaryotes have no membrane bound organelles
What organelles do plant cells have, that animal cells do not
- Permanent vacuole
- Chloroplast
What is photosynthesis, and what organelle is required for it to take place
- production of glucose using energy transferred by light
- chloroplasts
What organelle does a plant cell have, that fungi do not
Chloroplast
Describe the process where we start with gametes, and end with a foetus
- Gametes (haploid) are produced via meiosis, where the male gamete is sperm, the female is egg
- During fertilisation, the gametes fuse together to form a zygote (diploid)
- The zygote divides via mitosis, producing an embryo, which contains stem cells
- The stem cells continue to divide and differentiate into specialised cells
- Groups of similar specialised cells join together to form tissues
- Multiple tissues form organs
- Eventually the foetus is formed, and will continue to grow
Describe the function of stem cells
Stem cells are unspecialised cells, which can differentiate into specialised cells
Explain 3 adaptations of the root hair cell
- Root hair with a large SA, therefore faster rate of transport of mineral ions from the soil to the roots
- Many mitochondria, to produce more ATP in respiration, therefore active transport can occur at a higher rate
- Large vacuole to store more cell sap
Explain 3 adaptations of the red blood cell
- No organelles, therefore can store more haemoglobin, to carry more oxygen
- Biconcave shape, so larger SA, therefore faster diffusion of oxygen
- Flexible, so it can fit through narrow blood vessels
Explain 3 adaptations of the sperm cell
- Flagellum, therefore can move towards the egg for fertilisation
- Many mitochondria, to produce more ATP in respiration, to release more energy for movement
- Acrosome contains many enzymes, so the outer layer of the cell can be digested
Describe the function of nerve cells
(animals)
- Excitable, which allows nerve impulses to be sent
Describe the function of epithelial tissue
(animals)
- Covers surfaces, and is usually thin for efficient exchange
Describe the function of muscle tissue
(animals)
- Can contract, to create movement
Describe the function of connective tissue
(animals)
- Connective tissue joins parts of the body together
- provides protection and support
Describe the function of dermal tissue
(plants)
- Provides protection
- Helps reduce water loss
Describe the function of ground tissue
(plants)
- Its photosynthetic tissue
Describe the function of vascular tissue
(plants)
- Used for transport
- e.g. xylem and phloem
Explain why the stomach needs muscle tissue
- To churn and mix the stomach contents
Explain why the stomach needs the epithelium
- To protect the stomach wall, and produce secretions
Explain why the stomach needs connective tissue
- To hold all the other tissues together
What evidence proves that leaves are organs
- Leaves have different tissues
What 3 tissues are preset in leaves
- Vascular
- Ground
- Dermal
Explain the function of dermal tissue
- Protect and reduce water loss
Why do we need to prevent water loss
- Water is needed for photosynthesis, and for keeping the cells turgid, keeping the cells upright
Explain the function of ground tissues
Photosynthesis
What type of specialised cells make up the ground tissue, and how are they adapted to its function
- Palisade cells
- Contain many chloroplasts, which help absorb as much light as possible for photosynthesis
Explain the function of vascular tissue
- Transport
What are the 2 types of vascular tissues in plants
- Xylem
- Phloem
Describe the function of the Xylem
- Transports water
Describe the function of the Phloem
- Transports sugars
Describe what is meant by a tissue
- Similar specialised cells that work together to perform a specific function
What are the 4 types of tissues in animals
- Connective
- Epidermal
- Nervous
- Muscle
Why are capillaries not considered to be organs
- Only contain 1 type of tissue, the epidermal tissue
Why are arteries organs
- Contain 2 types of tissues: epithelial and muscular tissue
Describe the function of muscle tissues in the arteries
- Constricts, to reduce blood flow (vasoconstriction)
- Relaxes, to increase blood flow (vasodilation)
Describe what is meant by an organ system
- A group of organs that work together as a single unit, to carry out a life process
What are the 2 main organ systems in plants
- The shoot system
- The root system
Describe what is meant by the shoot system
- The system which transports food and water throughout the plant
- Includes leaves, stems and flowers
Describe what is meant by the root system
- The system which anchors the plant, and takes in water and nutrients
