Chapter 5 - Cells Structure & Organisation Flashcards
What is the role of cell surface membrane?
It controls the entry/exit of substances.
It is selectively permeable.
It maintains a constant internal environment in cells.
It has receptors for cell recognition.
What is the function of the nucleus?
It is the control centre of cells as it controls functions and activities of cells.
It produces an exact copy when cells divide.
It passes on genetic information to the new cells.
What is the function of chloroplasts?
It is the site of photosynthesis where it absorbs light energy to build glucose and starch.
It contains chlorophyll which traps the light energy.
What is the function of a cell wall?
It forms a rigid coating which provides mechanical support around plant cells.
It gives the plant cells specific shapes.
It is fully permeable.
It prevents bursting of plant cells.
What the function of vacuoles?
It stores salts, ions, sugars, waste & pigments in the cell sap.
It support plant cells and keep the cell firm (turgid).
It controls the water content of plant cells.
What is the function of cytoplasm?
It is a jelly-like fluid which is the site for chemical reactions in a cell.
It is mainly composed of water and contains enzymes, salts, organelles & organic molecules.
It provides physical structure for the cell.
Name the differences between plant and animal cells. (7)
- plant cells have a cell wall of cellulose & animal cells have no cell wall.
- plant cells have chloroplasts with chlorophyll & animals do not.
- plant cells have large permanent vacuole & animals cells sometimes have small temporary vacuoles.
- cytoplasm in plant cells form a layer at the edge of the cell & in animal cell the cytoplasm is found throughout.
- nucleus of plant cell is more to the edge & more centrally located in an animal cells
- plant cells are larger in size & animal cells are smaller in size
- plant cells are regular in shape & animals cells are irregular with many shapes.
Name the similarities of plant and animal cells. (4)
- plant and animal cells both have cell surface membranes present
- both have a nucleus with a nuclear membrane and pores.
- both have mitochondria present (animal cell more)
- both have cytoplasm present
Explain the difference between eukaryotic and prokaryotic cells.
Eukaryotic cells possesses a clearly defined nucleus with well-defined chromosomes located in the nuclear membrane and they are large in size.
Prokaryotic cells is usually a bacterium that doesn’t have a nucleus and has loops of DNA free in the cytoplasm.
Name 3 animal tissues.
- cardiac muscular tissue
- skeletal muscle tissue
- smooth muscular tissue
What is the function of the rough endoplasmic reticulum (rough ER)?
- it transports mRNA from the nucleus to the ribsomes.
- it synthesise ribosomes and proteins.
- it transports proteins to the rest of the cell.
What is the function of the ribosomes?
It is the site of protein synthesis.
What is the function of the mitochondria?
- it is the site of cellular respiration which release energy from glucose.
- it produces ATP during cell respiration.
What is the function of the secretory vesicles?
- it store, transports and digests cellular waste and products.
- it contains digestive enzymes that break down and destroy bacteria and unwanted organelles.
- it contains materials that are to be excreted from the cell.
Name the 7 levels of organisation.
- Chemical and molecular level
- Organelle level
- Cellular level
- Tissue level
- Organ level
- Organ systems
- The organism
