Namibia Senior Secondary Certificate (NSSC) Ordinary Level Biology Syllabus

Flashcards covering core biological definitions, equations, scientific skills, experiments, and assessment details from the NSSCO Biology Ordinary Level Syllabus (Code 6116).

What is the syllabus code for the NSSCO Biology Ordinary Level syllabus for Grades 10 & 11?

6116

How many guided learning hours is the NSSCO Biology syllabus designed for over its two-year duration?

About 130 guided learning hours.

By convention, how should a graph be titled and which axes should display the variables?

The heading must be the dependent versus independent variable; the independent variable is plotted on the x-axis (horizontal) and the dependent variable is plotted on the y-axis (vertical).

How should data points be plotted on a graph according to the syllabus guidelines?

Clearly marked as crosses ($\times$) or encircled dots ($\odot$); vertical crosses ($+$) may be used if a further curve is included.

What is the binomial system of naming species?

A system in which the scientific name of an organism is made up of two parts showing the genus and species.

What are the structural components of a virus recognized in the syllabus?

It is limited to a protein coat and genetic material.

What are the five recognized kingdoms of living organisms according to the syllabus conventions?

Prokaryotes (Prokaryotae), Protoctists (Protoctista), Fungi (Fungi), Plants (Plantae), and Animals (Animalia).

What are the four structures in the cytoplasm of a eukaryotic cell whose functions must be known?

Rough endoplasmic reticulum, ribosomes, vesicles, and mitochondria.

What provides the energy for diffusion?

The kinetic energy of random movements of molecules and ions.

How is active transport defined?

The movement of particles through a cell membrane from a region of lower concentration to a region of higher concentration using energy from respiration.

What chemical reagent is used to test for reducing sugars and what indicates a positive result?

Benedict's solution.

Which chemical tests are specified to test for starch, proteins, fats/oils, and vitamin C?

Iodine solution for starch, biuret test for proteins, ethanol test for fats and oils, and DCPIP test for vitamin C.

What is the base-pairing rule in the double helix structure of DNA?

A pairs with T, and C pairs with G.

What is the definition of a catalyst?

A substance that increases the rate of a chemical reaction and is not changed by the reaction.

How are enzymes defined?

Proteins that function as biological catalysts.

What is the balanced chemical equation for photosynthesis?

$6CO_2 + 6H_2O \rightarrow C_6H_{12}O_6 + 6O_2$ in the presence of light and chlorophyll.

What is the definition of a limiting factor?

Something present in the environment in short supply that restricts life processes.

How is ingestion defined?

The taking in of substances into the body through the mouth.

What is the distinction between mechanical digestion and chemical digestion?

Mechanical digestion is the breakdown of food into smaller pieces without chemical change to food molecules; chemical digestion is the breakdown of large, insoluble molecules into smaller, soluble molecules.

How is absorption defined in the alimentary canal?

The movement of small food molecules and ions through the wall of the intestine into the blood.

How is egestion defined?

The passing out of food that has not been digested or absorbed through the anus.

How does the cholera bacterium cause dehydration and diarrhoea?

It produces a toxin that causes secretion of chloride ions into the small intestine, causing osmotic movement of water into the gut.

What are the two specified functions of hydrochloric acid in gastric juice?

Killing bacteria in food and giving an acid pH environment for enzymes.

What is the definition of transpiration?

The loss of water vapour from plant leaves by evaporation of water at the surfaces of mesophyll cells followed by diffusion of water vapour through the stomata.

What is translocation?

The movement of sucrose and amino acids from the region of production or of storage to a region of utilisation or demand in respiration or growth.

What is the key protein conversion involved in blood clotting?

The conversion of fibrinogen to fibrin.

How is a pathogen defined?

A disease causing organism.

What is the difference between active immunity and passive immunity?

Active immunity is defence against a pathogen by antibody production in the body; passive immunity is a short-term defence against a pathogen by antibodies acquired from another individual (without memory cells being produced).

What is the balanced chemical equation for aerobic respiration?

$$C_6H_{12}O_6 + 6O_2 \rightarrow 6CO_2 + 6H_2O$$

What are the chemical equations for anaerobic respiration in muscles and in yeast?

In muscles: $\text{glucose} \rightarrow \text{lactic acid}$; In yeast: $C_6H_{12}O_6 \rightarrow 2C_2H_5OH + 2CO_2$.

What is deamination?

The removal of the nitrogen-containing part of amino acids to form urea.

How are gravitropism and phototropism defined?

Gravitropism is a response in which parts of a plant grow towards or away from gravity; phototropism is a response in which parts of a plant grow towards or away from the direction from which light is coming.

How is a synapse defined?

A junction between two neurones or between a neurone and an effector.

What is a reflex action?

A means of integrating and coordinating stimuli with responses of effectors.

What is the definition of a drug?

A substance taken into the body that modifies or affects chemical reactions in the body.

How is a hormone defined?

A chemical substance, produced by a gland and carried by the blood, which alters the activity of one or more specific target organs.

What is homeostasis?

The maintenance of a constant internal environment.

What is the biological definition of mitosis?

Nuclear division, giving rise to genetically identical cells.

What is meiosis?

A reduction division in which the chromosome number is halved from diploid to haploid resulting in genetically different cells.

What is the difference between self-pollination and cross-pollination?

Self-pollination is the transfer of pollen grains from the anther to the stigma of the same flower or another flower on the same plant; cross-pollination is the transfer of pollen from the anther to the stigma of a flower on a different plant of the same species.

How are growth and development defined in Topic 4.3.5?

Growth is an increase in dry mass and size; development is an increase in complexity.

What is the definition of a gene?

A length of DNA that codes for a protein.

What is the definition of an allele?

A version of the same gene.

How are genotype and phenotype defined?

Genotype is the genetic make-up of an organism in terms of the alleles present; phenotype is the observable features of an organism.

What is a gene mutation?

A change in the base sequence of DNA.

What is the definition of adaptive features?

The inherited functional features of an organism that increase its fitness.

How is natural selection defined?

The selection of only the best adapted organisms for survival and reproduction.

How is evolution defined in Topic 4.4.4?

A process of change over a period of time, described as the change in adaptive features of a population over time as the result of natural selection.

What is a trophic level?

The position of an organism in a food chain, food web, pyramid of numbers or pyramid of biomass.

What are the four roles of microorganisms in the nitrogen cycle specified in the syllabus?

Decomposition, nitrification, nitrogen fixation, and denitrification.

What is the definition of a community?

All of the populations of different species in an ecosystem.

What is the definition of an ecosystem?

A unit containing the community of organisms and their environment, interacting together.

How is sustainable development defined in Topic 5.4.2?

Development providing for the needs of increasing human population while preserving the environment.

What are the weightings, marks, and durations of Papers 1, 2, and 3 in the scheme of assessment?

Paper 1 (45 minutes, 40 marks, 30%); Paper 2 (1 hour 30 minutes, 80 marks, 50%); Paper 3 (1 hour 15 minutes, 40 marks, 20%). Total marks: 160.

According to the ASE conventions used in the syllabus, what unit must be used in place of 'l' or 'litre'?

$$dm^3$$