One cell structure found in ALL plant cells but never in animal cells is the:
A nucleus
B cell membrane
C cell wall
D mitochondrion
Which statement below about plant and animal cells is correct?
A Animal cells are usually bigger than plant cells.
B Most animal cells have an irregular shape because they do not have a cell wall.
C Only animal cells rely on their cell membrane for controlling the movement of substances into and out of the cell.
D Both types of cells contain chloroplasts.
Which statement about DIFFUSION is NOT CORRECT?
A It is the net movement of substances from a region of higher concentration to a region of lower concentration against a concentration gradient.
B The rate at which diffusion occurs into or out of a cell is affected by the surface:volume ratio of the cell.
C Diffusion is responsible for the movement of both food into and wastes out of many single-celled organisms.
D Molecules can only move in one direction when a substance is diffusing into or out of a cell.
Which statement about OSMOSIS is NOT CORRECT?
A Osmosis is a special type of diffusion.
B Osmosis always involves the movement of water .
C Osmosis is only possible if there is a semipermeable membrane separating solutions of different concentrations.
D In osmosis solute particles move from regions of higher concentration to regions of lower concentration.
An ENZYME is:
A Any substance which acts as a catalyst.
B A protein which acts on a specific substrate by means of its active site.
C Any substance which assists in the breakdown of food.
D A special type of cell that has a part called the "active site".
Which of the following is the best definition of the term "nutrition"?
A Taking in of organic substances and mineral ions containing the raw materials and energy for growth and repair.
B Obtaining the nutrients - proteins,carbohydrates, amino acids, vitamins and minerals, needed for a healthy diet.
C Taking in of organic substances and mineral ions containing the raw materials and energy for growth and repair, and absorbing and assimilating them.
D Removal from organisms of toxic materials which were produced as wastes.
The ability to detect or sense changes in the environment (stimuli) and to make responses is known as:
A responsivity
B sensitivity
C reactivity
D adaptability
Which of the following is the best explanation as to why there is a limit to the size that cells can grow to?
A Bigger cells require more nutrients and energy to survive.
B The bigger a cell, the smaller its surface area to volume ratio and the slower materials diffuse into or out of the cell.
C Even with cell walls, cells cannot support themselves once they get bigger than a certain size.
D One cell can only perform limited functions, it is better to have many cells with different types of cells performing different functions.
"Active transport" is the movement of:
A molecules from a region of their higher concentration to a region of their lower concentration.
B particles from a region of lower concentration to a region of higher concentration using energy from respiration.
C urine by relaxation of a sphincter muscle in the bladder.
D water through a partially permeable membrane from a more dilute to a more concentrated solution.
The diagram shows an experiment to demonstrate the movement of molecules. After one hour, the water in the beaker turned red.
What is the most likely reason for this colour change?
A Molecules of red ink move through the membrane by diffusion.
B Molecules of red ink move through the membrane by osmosis.
C Molecules of water move through the membrane by diffusion.
D Molecules of water move through the membrane by osmosis.
The diagram shows water and sugar molecules on either side of a partially permeable membrane.
What happens during osmosis?
A More sugar molecules pass through the membrane from X to Y than from Y to X.
B More sugar molecules pass through the membrane from Y to X than from X to Y.
C More water molecules pass through the membrane from X to Y than from Y to X.
D More water molecules pass through the membrane from Y to X than from X to Y.
Which diagram shows the changes in appearance of a plant cell when it remains in a concentrated sugar solution for thirty minutes?
A
B
C
D
The diagram shows a plant cell.
What is the appearance of this cell after it has been placed in pure water for 30 minutes?
A student cuts out four pieces of carrot root of equal size. The pieces are treated as shown in the diagram, and then left for two hours.
After two hours, which piece of carrot will be the smallest?
The diagrams show how a cell appears under the microscope at the start of an experiment and after it has been placed in a dilute solution of salts for 5 minutes.
Which statement explains what happens?
A Dissolved salts enter the cell by diffusion.
B Dissolved salts leave the cell by diffusion.
C Water enters the cell by osmosis.
D Water leaves the cell by osmosis.
Four biological processes are listed. 1 egestion 2 excretion 3 nutrition 4 respiration Which processes are characteristics of all living organisms?
A 1, 2, 3 and 4
B 1, 2 and 3 only
C 1, 2 and 4 only
D 2, 3 and 4 only
When an apple is cut, the cut surface quickly turns brown. This is due to enzyme action. Which action destroys the enzyme?
A brushing the cut surface with a strong sugar solution
B cutting the apple into smaller pieces
C placing the cut apple in boiling water
D placing the cut apple in cold water
Which is the correct description of diffusion?
A net movement of particles from a region of higher concentration to a region of lower concentration down a concentration gradient.
B net movement of particles from a region of higher concentration to a region of lower concentration against a concentration gradient
C net movement of particles from a region of lower concentration to a region of higher concentration down a concentration gradient
D net movement of particles from a region of lower concentration to a region of higher concentration against a concentration gradient
Which characteristic of living organisms describes the taking in of materials for energy, growth and development?
A absorption
B nutrition
C photosynthesis
D respiration
What is "osmosis"?
A the movement of salt across a cell wall
B the movement of salt across a partially permeable membrane
C the movement of water across a cell wall
D the movement of water across a partially permeable membrane
A biologist keeps a potted plant in a laboratory. Which feature of the potted plant shows that it is a living organism?
A It grows larger over time.
B It has green leaves.
C The compost in the pot dries after he waters it.
D The stems contain xylem.
How are root hair cells adapted for absorption of water?
A large surface area
B thick cell wall
C many chloroplasts
D no nucleus
The diagram shows a ciliated cell. Which row shows where ciliated cells are found in the human gas exchange system and their correct function?
A Location of ciliated cells = bronchi and trachea; Function of ciliated cells = move mucus away from lung.
B Location of ciliated cells = bronchi only ; Function of ciliated cells = move mucus away from lung.
C Location of ciliated cells = bronchi only ; Function of ciliated cells = move mucus towards the lung.
C Location of ciliated cells = trachea only ; Function of ciliated cells = move mucus towards the lung.
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