HIGHER HUMAN BIOLOGY UNIT
1 EXAM QUESTIONS AND
ANSWERS
Selectively Permeable Membrane - Answer- Cell membrane controls movement of
some materials in and out of cells.
Diffusion - Answer- The movement of molecules from a high concentration to a low
concentrate down a concentration gradient.
Osmosis - Answer- The diffusion of water from a high water concentration to a low
concentration.
Active Transport - Answer- Chemical ions are taken in and out of cells against a
concentration gradient. Selective. Requires energy.
Endocytosis - Answer- The process by which a cell engulfs materials and takes them
into the cell.
Phagocytosis - Answer- When the cell engulfs relatively large substances e.g. bacteria
Pinocytosis - Answer- The cell membrane surrounds the extracellular fluid and encloses
it in a vacuole.
Exocytosis - Answer- The process by which a cell passes material out of the cell into
surrounding fluid.
Autoimmune - Answer- Immune reaction directed against a person's own tissue.
Natural Immunity - Answer- An individual's own genetic ability to fight off disease.
Macrophage - Answer- An white blood cell that engulfs pathogens.
B-Lymphocyte - Answer- Produces Y shaped protein molecules in response to the
surface antigens of bacteria and viruses.
Humoral Response - Answer- The branch of acquired immunity that involves the
activation of B cells and that leads to the production of antibodies, which defend against
bacteria and viruses in body fluids.
, Memory Cells - Answer- Cells which quickly produce more of the plasma cells if an
antigen enters the body a second time.
Killer T-cell - Answer- Recognise and kill cells infected by a virus or bacteria.
Cell Mediated Response - Answer- The branch of acquired immunity that involves the
activation of T-lymphocytes, which defend against infected cells.
Helper T-cell - Answer- Activate other immune cells (B-lymphocytes and killer T-
lymphocytes).
Thymus Gland - Answer- Processes T-lymphocytes.
Lymph Nodes - Answer- Both B and T-lymphocytes mature and are activated here.
Innate Immunity - Answer- Inborn immunity. Includes first and second lines of defense
again viruses and bacteria.
Acquired Immunity - Answer- Refers to the ways by which an individual becomes
immune to antigens.
Allergy - Answer- An exaggerated response by the body to foreign molecules.
Virus - Answer- A protein coat and nucleic acid (DNA or RNA).
Genes - Answer- Specific regions of chromosomal DNA that determine characteristics
of an organism.
Chromosome Complement - Answer- The number of chromosomes present in the
nucleus of each body cell (46 in a human).
Karyotype - Answer- The chromosomes that make up the human chromosome
complement arranged into their homologous pairs.
Sex Chromosomes - Answer- Set 23 of the homologous pairs. XX or XY.
Autosomes - Answer- The other 22 homologous pairs of chromosomes.
Homologous Pairs - Answer- Matching pairs of chromosomes.
Gametes - Answer- X or Y chromosomes. X is female. Y is male.
Meiosis - Answer- Cell division in which the number of chromosomes in a gamete
mother cell is reduced from two sets to a single set.
Haploid - Answer- Single set of chromosomes.
1 EXAM QUESTIONS AND
ANSWERS
Selectively Permeable Membrane - Answer- Cell membrane controls movement of
some materials in and out of cells.
Diffusion - Answer- The movement of molecules from a high concentration to a low
concentrate down a concentration gradient.
Osmosis - Answer- The diffusion of water from a high water concentration to a low
concentration.
Active Transport - Answer- Chemical ions are taken in and out of cells against a
concentration gradient. Selective. Requires energy.
Endocytosis - Answer- The process by which a cell engulfs materials and takes them
into the cell.
Phagocytosis - Answer- When the cell engulfs relatively large substances e.g. bacteria
Pinocytosis - Answer- The cell membrane surrounds the extracellular fluid and encloses
it in a vacuole.
Exocytosis - Answer- The process by which a cell passes material out of the cell into
surrounding fluid.
Autoimmune - Answer- Immune reaction directed against a person's own tissue.
Natural Immunity - Answer- An individual's own genetic ability to fight off disease.
Macrophage - Answer- An white blood cell that engulfs pathogens.
B-Lymphocyte - Answer- Produces Y shaped protein molecules in response to the
surface antigens of bacteria and viruses.
Humoral Response - Answer- The branch of acquired immunity that involves the
activation of B cells and that leads to the production of antibodies, which defend against
bacteria and viruses in body fluids.
, Memory Cells - Answer- Cells which quickly produce more of the plasma cells if an
antigen enters the body a second time.
Killer T-cell - Answer- Recognise and kill cells infected by a virus or bacteria.
Cell Mediated Response - Answer- The branch of acquired immunity that involves the
activation of T-lymphocytes, which defend against infected cells.
Helper T-cell - Answer- Activate other immune cells (B-lymphocytes and killer T-
lymphocytes).
Thymus Gland - Answer- Processes T-lymphocytes.
Lymph Nodes - Answer- Both B and T-lymphocytes mature and are activated here.
Innate Immunity - Answer- Inborn immunity. Includes first and second lines of defense
again viruses and bacteria.
Acquired Immunity - Answer- Refers to the ways by which an individual becomes
immune to antigens.
Allergy - Answer- An exaggerated response by the body to foreign molecules.
Virus - Answer- A protein coat and nucleic acid (DNA or RNA).
Genes - Answer- Specific regions of chromosomal DNA that determine characteristics
of an organism.
Chromosome Complement - Answer- The number of chromosomes present in the
nucleus of each body cell (46 in a human).
Karyotype - Answer- The chromosomes that make up the human chromosome
complement arranged into their homologous pairs.
Sex Chromosomes - Answer- Set 23 of the homologous pairs. XX or XY.
Autosomes - Answer- The other 22 homologous pairs of chromosomes.
Homologous Pairs - Answer- Matching pairs of chromosomes.
Gametes - Answer- X or Y chromosomes. X is female. Y is male.
Meiosis - Answer- Cell division in which the number of chromosomes in a gamete
mother cell is reduced from two sets to a single set.
Haploid - Answer- Single set of chromosomes.
