Cells Flashcards
What does a cytologist do?
Studies the structure and function of cells.
What are the three parts commonly found in cells?
Cell membrane
Nucleus
Cytoplasm
What structures are usually found in the cytoplasm?
Mitochondria
Ribosomes
What is the function of the cell membrane?
To control the passage of substances in and out of the cell.
What is the function of the nucleus?
Contains genetic material, and controls the activities of the cell.
What is the cytoplasm?
The site where most chemical reactions take place.
What is the function of the mitochondria?
To release energy by aerobic respiration.
What is the function of ribosomes?
The place where protein synthesis takes place- to produce proteins such as enzymes, insulin and haemoglobin.
What is a cell?
The basic unit of the human body.
What is a tissue?
A group of cells with similar structure and function.
What is an organ system?
A group of organs that perform a particular function.
Give an example of an organ system.
The digestive system
The circulatory system
The breathing system
What organ is part of more than one organ system?
The pancreas.
What do cells need to function efficiently?
Energy, nutrients and oxygen.
What is diffusion?
The movement of molecules from high to low concentration.
How do nutrient molecules reach body cells?
Via the digestive system.
How does oxygen reach body cells?
Via the lungs.
What happens to waste molecules in cells?
They must be removed.
What is osmosis?
The movement of water through a partially permeable membrane.
Why is it important to regulate the solute-water balance of the blood?
Because human cells are easily damaged by the entry or loss of too much water.
What are enzymes?
Catalysts for reactions.
What factors can affect the function of enzymes?
pH and temperature
What is respiration?
The release of energy within a cell.
What is the main supply of energy for the body?
Food.
What are glycogen and fats?
Stored forms of energy.
What is energy needed for?
Movement, growth, keeping warm, building large molecules from smaller ones.
What gas is needed for aerobic respiration?
Oxygen.
What gas is a product of aerobic respiration?
Carbon Dioxide.
When may anaerobic respiration occur?
During vigorous physical exercise, when insufficient oxygen is available.
What are the disadvantages of anaerobic respiration?
It releases a limited amount of energy, leads to lactic acid production and muscle fatigue.
