This chapter is discussed under the following subheadings: background of the study, statement of the problem, purpose of the study, significance of the study, research question, research hypotheses, delimitation of the study, limitation of the study and definition of terms.
1.1 Background of the Study
Biology is a branch of science concerned with the study of life or living things. According to Parker (2013), biology can be divided into smaller units like anatomy, morphology, histology, physiology. Parker further stated that the knowledge gained from investigation in biology is applied in various fields for example, agriculture, wildlife management, forestry, medicine, genetics and teaching.
There are unifying concepts that govern the study and research in biology. In general, biology recognizes the cell as the basic gene and unit of heredity and sees evolution as the engine that propels the synthesis and creation of new species. It is also known today that all the organisms survive by consuming and transforming energy and by regulating their internal environment to maintain a stable and vital condition known as homeostasis.
Some of the usefulness of biology as cited by Sarojiet (2013) is as follows:
i. Scientific research and development of new tools and techniques which in variable improve the quality of lives.
ii. Finding applications in medicine, dentist veterinary, science, agriculture and horticulture.
iii. Biotechnonology which include fields like genetic engineering and hybrid technology.
iv. Dealing with ecological problems such as over population, food storage, erosion, pollution and diseases.
v. It promotes the understanding of the relation of man to his environment as well as acknowledges interrelationships that exist between living and non-living things.
vi. It brings into sharper focus, the need to maintain good health such as using clean water, clean air, having good sanitation, vaccination against infectious diseases, exercise and adequate rest as well as eating balanced diet.
vii. It helps an individual to understand himself, the part of his body and their functions.
viii. It also questions superstitious caused by sustained interest arising from a comprehension of the causes of events, etc.
Parker (2013) stated that genetics is a concept in biology that concerned with biological inheritance, that is, with the causes of the resemblances and differences among related individuals. It is a common knowledge that after sexual reproduction the resulting offspring tends to look like their parents in one or more ways. This resemblance may be related to the immediate parents or even to the grandparents. This tendency of the offspring to look like their parents or grandparents is a phenomenon which goes on from generation to generation. This is due to certain characteristics or traits which the offspring have inherited from their parents.
Genetics then is a concept in biology that deals with inheritance of traits or characteristics from parents to offspring, such as height, and skin colour which are transmitted from parents to offspring during sexual reproduction. The ways and manner by which these characters are inherited from parents is known as heredity.
Green (2010) observed that sometimes in nature, certain changes suddenly occur in the chromosomes without necessarily destroying them. Such changes are known as mutations. When mutation occurs, it will lead to the production of offspring with marked differences in appearance from their members and parents. This condition is known as genetic variation. This variation is based in alleles of genes in a gene pool. It is brought about by random mutation which is a permanent change in the chemical structure of a gene. For example difference in blood group, pattern of finger print, skin colour and height.
The practical application of knowledge of genetics have helped in no small measure to solve, if not completely, at least in part, some human problems, such as improvement measures to produce new breeds of crops and animals to overcome the problem of food shortages and starvation, reducing the incidence of hereditary diseases such as sickle cell through marriage counselling, determination of child’s paternity in case of disputed parentage, blood transfusion and crime detection by the use of finger prints. Genetics as a concept in biology has contributed immensely to personal and social education of the people. It develops in students’ attitudes and values necessary for tolerating a range of opinions needed in solving human problems.
Inspite of the relevance of genetics to human population and in academics, the teaching of genetics become increasingly deplorable in senior secondary schools, due to the methods or approaches used. There are many approaches applied by a teacher to make students learn. Genetics is considered a difficult concept in biology and so new methods and approaches for teaching genetics should be explored to bring meaning, relevance and interest of students for learning the concept.
Active teaching approaches that could be used to arouse and stimulate students’ interest towards the learning of genetics is using of electronic media such as video-learning and mind mapping approaches. These electronic approaches incorporate practical experiences for students’ knowledge when applied accordingly. Eze (2014) stated that students understand better when they have practical experiences. The approach used by a teacher in any teaching learning situation determines to a large extent students’ academic achievement.
Video-learning approach is an approach of teaching which the video is used as an instructional material. Abubakar (2011) is of the view that video-learning has high potentials in teaching the concept of genetics. Videos are modern instructional materials that can transit and transfer learning experiences through sound and motion simultaneously. It has the ability to be played back. Video-learning approach provides students the necessary options for making use of video materials to enhance or promote students’ achievement.
Abdulrasheed (2012) observed that teacher effectiveness depends on the use of appropriate teaching technique and successful learning. Video-learning approach is capable of motivating students’ interest to learn and thus promote their academic achievement. The benefits of using video in teaching the concept of genetics provide and include a sensory experience that allows concepts and ideas come to life as students are guided through each adventure. Videos enable the students to study materials at hand effectively and improve their reading and literacy skills simultaneously. It provides the option for the students to read the presentation as well as watching or listening.
Robertson (2012) stated that video-learning approach play vital role in teaching and learning the concept of genetics in biology. It can stimulate, motivate students’ interest and induces longer retention of factual ideas as students come into contact with what is being taught. Ibrahim (2012) observed that video-learning has greatly improved the achievement of children with special needs and slow learning ability.
Guo (2014) asserts that video-learning approach reduces abstraction as well as boredom among students in the classroom. Teacher utilization of video-learning approach will therefore be of interest to students because of the benefits of colour, sound and motion attached to video-compact disc package.
Mind-mapping approach on the other hand is a visual form of note taking that offers an overview of a topic and its complex information, allowing students to comprehend, create new ideas and connections. Through the use of colours, images and words, mind mapping encourages students to begin with a central idea and expand outward to move in-depth into sub-topics.
Abba (2011) stated that mind-mapping is a simple technique for drawing information in diagrams, instead of writing it in sentences. The diagrams always take the same basic format of a tree, with a single starting point in the middle that branches out, and divides again and again. The tree is made up of word or short sentences connected by lines. The lines that connect the words are part of the meaning.
Lakpini (2012) observed that mind-mapping approach are ideal for teaching the presenting concepts in the classroom as they provide a useful focus for students delivering an overview of the topic without superfluous information. It is perfect for introducing a new subject in a way which is accessible and easy to follow. Mind-map is an excellent way to present concepts and ideas. Teachers can now keep the students engaged and amazed as the lesson branches smoothly. Animate to show the next point. Therefore mind-mapping approach according to Kinchin (2015) is a strategy that helps students organize their cognitive frameworks into more powerful integrated patterns.
Jegede (2010) have observed that mind-mapping approach can improve the achievement of students in the concept of genetics in biology through meaningful learning and help students learn independently. The diagrammatic form of mind-mapping is a useful tool for successful study skill and independent learning as students can recall information more easily through creating mind-maps and can show understanding of cause and effect.
Example of mind-mapping using Mendel’s Law of dominant of genes (Mendel’s first law of inheritance)
Let: T represent tall man (dominant)
t represent short woman (recessive)
Parental phenotypes Tall man x Short woman
Parent gamete T T t t
F1 generation Tt Tt Tt Tt
*The genotype of all the F1 children is Tt (tall children)
*The phenotype is all tall children but (t) remain district in the present of (T) dominant.
To obtain the second filial generation (F2) the F1 children are self-cross.
The F1 children are self-cross
Parent Tall man x Short woman
Gamete T T t t
F2 generation TT Tt Tt tt
The genotypes of all the F2 children are:
1. TT 2. Tt 1. tt
* The genotypic ratio is 1:2:1
* Their phenotypes are:
3 tall children
1 short child
Their phenotypic ratio is 3:1
The influence of gender on students’ academic achievement had been a major concern to educational researchers for long, yet no consistent result had emerged. Researches according to Atauyo (2011) has been conducted to bare the superiority of one gender over the other in certain situations, driven home the point that a particular gender or sex has always been performing and achieving more than the other from time immemorial. To prove this, historical achievements of the male and female gender in all endeavours are always compared so as to make inferences. Madu (2011) noted that gender affects behaviour both biologically and socially, these influences propels of a particular gender in an aspect of life, while regressing the same gender in another. His opinions therefore suggest that there are aspects of life that one gender can really excel but cannot excel in others.
In addition, researchers according to Sadovnik (2012) assert that gender remain competitive in every aspect generally; if aspects are analyzed in isolation a particular gender would be more dominant. Also, scholars like Butler (2010) argued that the above statement may be true but not applicable in all situations especially when both gender has what it takes to perform.
In education, it is a situation whereby achievement is attributed or attached to gender in different subject, concepts and field of study. Some scholars who embarked upon researches in the area of gender and achievement came out with different findings depending on the subject, while some tend to be equivocal, others held their stance supporting that one gender performs more than the other in different subjects and concept.
Pezaris (2011) observed the differences in the cognitive abilities of students in senior secondary school. Females outperform males on several verbal skills tasks, verbal reasoning, verbal fluency, comprehension and understanding logical relations. Males on the other hand perform better on mathematics and scientific skills than females. But in recent times experience show the upsurge of successful female scientists in all areas like medicine, pharmacy, petrochemical, physics and teaching.
Etukudo (2010) posits that this then creates a doubt in the fields of science and mathematics dominated by males. This improvement is as the result of using an appropriate approach in teaching. This study set out to compare the effects of video-learning and mind-mapping approaches on biology students’ academic achievement in genetics.
Isiaka (2011) researched on the effectiveness of video as a media found that video group did significantly better than the mind-mapping group. He concluded that although mind-mapping is also good for teaching in that it can capture students thought and bring them to life visual form, but video-learning approach is the best and more effective medium of approach for teaching and learning in the school. Students’ interest and retention could be aroused through the use of video-learning approach more than mind-mapping approach. Adegoke (2010) also researched on the effects of video-taped instruction and observed that the experimental group/video-taped students acquired better knowledge, retention and improved comprehensive skills more than the control group/mind-mapping who could not retain what they were taught in a long time, in that mind map is basically a diagram that connects information around a central subject.
1.2 Statement of the Problem
Given the high value placed on the concept of genetics in biology in Nigerian secondary school curriculum, and the nature of the concept, the need to teach genetics effectively through an effective approach is indisputable. Some of the problems affecting the teaching and learning of biology in general are the meaningless of the concept of genetics. Lack of the use of appropriate approach of teaching, video materials are generally lacking in secondary schools. This hampers the effective teaching of the concept of genetics in biology in senior secondary schools.
In incidence of ineffective teaching and lack of the use of appropriate approach of teaching genetics has resulted in low achievement in the school certificate examinations (Osokoya, 2016). Abimbola (2011) revealed that inappropriate approaches presently employed in teaching biology in most public secondary schools is inadequate or not effective. In few schools, laboratory attendant employed are school dropouts with no basic knowledge on how to prepare electronic media such as vidoes and mind mapping materials for practical. In most cases, these laboratory attendants lack technical know-how to operate, maintain, repair or service the few available video compact disc and mind mapping softwares.
Barford (2016) stated that lack of use of the educational video to teach the concept of genetics causes failure in biology examination. According to Austin (2016), teachers’ incompetency on the use of mind-mapping approach to teach the concept of genetics makes learning boring and meaningless to the students. This also causes poor performance of students in external examination. Sex difference discouragement, according to Lenga (2010) makes a female student to develop low self-esteem, lack of self-confidence and a negative attitude towards genetics. This affects her achievement in the concept of genetics in biology. Perhaps, this may be the case in the secondary schools where discouraging statement such as ‘Art belongs to girls and Sciences belongs to boys’ (Zember, 2011). This discourage the girls including the talented once from being serious in science classes.