JK-TK/Newdata huggingface dataset:
They are called synovial joints. They include hinge joint and ball and socket joint. Hinge joint
e.g. knee joint. The joint allows movement in one plane. Ball and socket joint. e.g., hip joint. The joint allows rotation in all directions. Types, Locations and Function of Muscles
There are three types of muscles, located at various parts of the body. In order to function all use energy in form of ATP. These include smooth, skeletal and cardiac muscles. Smooth Muscle (Involuntary Muscles)
These are spindle-shaped and contain filaments with myofibrils. Each muscle is bound by plasma membrane. They are found lining internal organs such as alimentary canal, bladder, and blood vessels. They are controlled by involuntary part of the nervous system. They are concerned with movement of materials along the organs and tubes. They contract slowly and fatigue slowly . Skeletal Muscle (striated or voluntary muscle)
Skeletal muscles are striated and have several nuclei. They are long fibres each containing myofibrils and many mitochondria. They have cross-striations or stripes. They are also called voluntary muscles because the contraction is controlled by voluntary nervous system. They are surrounded by connective tissue and are attached to bones by tendons. Their contraction brings about movement of bone, resulting in locomotion. They contract quickly and fatigue quickly. Cardiac Muscle
Consist of a network of striated muscle fibres connected by bridges. Are short cells with numerous mitochondria and uninucleate. They are found exclusively in the heart. Contractions of cardiac muscles are generated from within the muscles and are rhythmic and continuous hence they are myogenic. They do not tire or fatigue. The rate can be modified by involuntary nervous system. Their contractions result in the heart pumping blood. Role of muscles in movement of the human arm
Muscles that bring about movement are antagonistic, i.e. when one set contracts the other relaxes. Antagonistic muscles of human forelimb
The biceps muscles of the forelimb act as flexors while the triceps muscles act as extensors. The biceps has its point of origin on the scapula and the point of insertion on the radius. The triceps has its points of origin on the scapula and humerus and is inserted on the ulna. When the muscles contract, the limb acts as a lever with the pivot at the joint.
The biceps has its point of origin on the scapula and the point of insertion on the radius. The triceps has its points of origin on the scapula and humerus and is inserted on the ulna. When the muscles contract, the limb acts as a lever with the pivot at the joint. Contraction of biceps muscles bends (flexes) the arm while contractions of triceps extends the arm. Practical Activities
To observe prepared slides of transverse section of stems of herbaceous and woody plants. Permanent slides of transverse sections of:
Herbaceous plant and Woody plant are obtained. The permanent slide of a herbaceous plant is placed onto the stage of the microscope. Observations under the low power and medium power objective is made. A plan diagram is drawn and labelled. The permanent slide of a woody plant is placed on the stage of the microscope. Observations under the low power and medium power objectives are made. A plan diagram is drawn and labelled. In both cases, support tissues such as parenchyma, collenchyma, sc1erenchyma and xylem are observed. To observe wilting in young herbaceous plants. A herbaceous potted plant e.g. bean plant is obtained. The plant is placed on the bench near a window and left for 3 days without watering on the third and subsequent day. The shoot droops due to fall in turgor pressure; caused by water loss. To examine the exoskeleton in an arthropod. Obtain a beetle and observe the external structure. The exoskeleton is on the outer surface with muscles attached on inner side. The exoskeleton is hardened by chitin. Movement is due to joints on the limbs. Also examine various shed cocoons of insects e.g., butterfly. To observe the external features of a finned fish. Fresh Tilapia is obtained and placed on a tray. Observations are made on the external features of the fish. A labelled drawing is made. Features like scales, fins a streamlined body and an operculum are seen. Opened operculum reveals the gills. To examine bones of the axial skeleton of a rabbit. Bones of the vertebra column are obtained. These are cervical, thoracic, lumbar and sacral. For each of the bones the distinguishing features are listed down. Labelled drawings of the anterior and lateral views is made. To observe bones of appendicular skeleton.
For each of the bones the distinguishing features are listed down.

Labelled drawings of the anterior and lateral views is made.

To observe bones of appendicular skeleton.

Bones of pectoral girdle and fore limb are obtained i.e., scapula, humerus, ulna and radius.

Labelled drawing of each bone is made.

Observations on how the bones articulate with one another is made.

Bones of pelvic girdle and hind limbs are obtained i.e., pelvic girdle, femur, tibia and fibula.

Labelled drawings of each, bone is made.

The distinguishing features of each bone is noted.

Observations on how the bones articulate with one another is made.

END
BEST WISHES
Primary and secondary growths
investigate primary and secondary growth in a seedling
Explain the role of hormones in regulation of growth and development in plants
Explain Apical dominance in plants
Define metamorphosis
Distinguish between complete and incomplete metamorphosis
Describe complete metamorphosis in housefly and anopheles mosquito
Describe incomplete metamorphosis in a cockroach
Describe and explain the Role of growth hormones in metamorphosis in insects
Observe metamorphosis in some insects
Classification II
General Principles of Classification
Classification is the science that puts organisms into distinct groups to make their study easy and systematic. Modern scientific classification is based on structure and functions. Organisms with similar anatomical and morphological characteristics are placed in one group while those with different structures are grouped separately. Modern studies in genetics and cell biochemistry are used to give additional help in classifying organisms. There are seven major taxonomic groups. The kingdom is the largest group. Others are phylum (division for plants) class, order, family, genus and species, the smallest. Binomial Nomenclature
Living organisms are named using Latin or Latinised names. Every organism has two names. This double naming is called binomial nomenclature. This system of naming was devised by Carolus Linnaeus in the 18th Century. The first name is the generic name - the name of the genus. The second name is the name of the species. The generic name starts with a capital letter while that of the species starts with a small letter. The names are written in italics or are underlined in manuscripts. Examples:
Bean =Phaseolus vulgaris. Phaseolus is the generic name,
vulgaris is specific name. Dog =Canis familiaris. Canis is the generic name
,familiaris the specific name. General Characteristics of Kingdoms
Organisms are classified into five kingdoms. Monera,
Protoctista,
Fungi,
Plantae
Animalia. Viruses do not fit neatly into any of the above kingdoms. They are simple and not cellular. They are metabolically inactive outside the host cell. Most of them can be crystallised like chemical molecules. Therefore they do not exhibit the characteristics of living organisms.
They are metabolically inactive outside the host cell. Most of them can be crystallised like chemical molecules. Therefore they do not exhibit the characteristics of living organisms. Examples of Organisms in Each Kingdom and Their Economic Importance
Kingdom Monera
General Characteristics
Unicellular and microscopic
Some single cells ,others colonial
Nuclear material not enclosed within nuclear membrane-prokaryotic
Have cell wall but not of cellulose. Have few organelles which are not membrane bound
Mitochondria absent
Mostly heterotrophic, feeding saprotrophically or parasitically,some are autotrophic. Reproduction mostly asexual through binary fission
Most of them are anaerobes but others are aerobes
Most move by flagella
Examples include Escherichia coli, Vibrio cholerae and Clostridium tetani. Spherical known as Cocci. Rod shaped - e.g. Clostridium tetani
Spiral shaped e.g. sprilla
Coma shaped- Vibrios -e.g., Vibrio cholerae. Economic importance of bacteria Benefits to man include:
They are used in food processing e.g., Lactobacillus used in processing of cheese, yoghurt. Involved in synthesis of vitamin Band K, in humans and breakdown of cellulose in herbivores. Genetic Engineering
Bacteria are easily cultured and are being used for making antibiotics, aminoacids and enzymes e.g. amylase, and invertase e.g., Escherichia coli. Nutrient cycling:
Saprophytes
They are involved in decomposition of dead organic matter. They are useful in the nitrogen cycle. Nitrogen fixing and nitrifying bacteria. They increase soil fertility. Modem sewage works use bacteria in treatment of sewage. Cleaning oil spills in oceans and lakes. Harmful Effects
Bacteria cause disease:
To humans (e.g. Cholera). To animals (e.g. Anthrax). Bacteria cause food spoilage. Others cause food poisoning e.g. Salmonella. Denitrifying bacteria reduce soil fertility e.g., Pseudomonas denitrificans. Kingdom Protoctista
Examples include ;
Algae such as spirogyra, Chlamydomonas, euglena, Sargassum
And protozoa such as amoeba, paramecium and Trypanosoma.
Salmonella. Denitrifying bacteria reduce soil fertility e.g., Pseudomonas denitrificans. Kingdom Protoctista
Examples include ;
Algae such as spirogyra, Chlamydomonas, euglena, Sargassum
And protozoa such as amoeba, paramecium and Trypanosoma. General Characteristics
They are said to be eukaryotic since their nucleus is bound by a membrane
Most are mobile, and use flagella, cilia and pseudopodia. Some are sessile. They reproduce mainly asexually, by binary fission, fragmentation and sporulation. Some reproduce sexually by conjugation. Some are heterotrophic e.g. paramecium. Others are autotrophic e.g. spirogyra. Economic importance of protoctista
Algae are the primary producers in aquatic food chains. They release a lot of oxygen to the atmosphere. Some cause human diseases like malaria and amoebic dysentry ,sleeping sickness
Some are source of food for humans e.g. sargassum is a source of iodine
Skeletons of diatoms used in paint making. Spirogyra: They have spiral chloroplast. They are green, thread-like filaments
Chlamydomonas:
This is a unicellular green algae and has a cup shaped chloroplast. They move towards light using the flagella
Cilia assist the organism to move. The shape is due to the presence of a thin flexible pellicle. Kingdom Fungi
Multicellular fungi are made of thread-like structures called hyphae (singular hyphae) that form a mycelium. .e.g.Saccharomyces cereviseae(bread yeast). Others include Penicillium, Rhizopus, and edible mushroom
Economic Importance of Fungi
Beneficial Effects
Some fungi are used as food e.g. mushrooms. Some are decomposers which enhance decay to improve soil fertility - recycling of nutrients e.g., toadstools. Some are useful in brewing and bread making e.g., yeast. Yeast is used as food - a rich source of Vitamin B. Some are useful in production of antibiotics e.g., Penicillium griseofulvin. Used in sewage treatment e.g., Fusarium spp. Harmful Effects
Some cause food poisoning by producing toxic compounds e.g.
Some are useful in production of antibiotics e.g., Penicillium griseofulvin. Used in sewage treatment e.g., Fusarium spp. Harmful Effects
Some cause food poisoning by producing toxic compounds e.g. Aspergillus flavus which produces aflatoxins. Some cause food spoilage, fabric and wood spoilage through decomposition. Some cause diseases to humans e.g., athlete's foot and ringworms. Others cause diseases to plants e.g., potato blight (Irish potatoes) rust in tomatoes and smuts in cereals. Kingdom Plantae
General Characteristics
They are multicellular and eukaryotic. They are photosynthetic and have a pigment chlorophyll. Their cells have cellulose cell walls. They reproduce sexually, others asexually. Kingdom Plantae has three major divisions:
Bryophyta,
Pteridophyta
Spermatophyta. Division Bryophyta
These include mosses and liverworts. Plant body is not differentiated into root, stem and leaves. They have simple structures which resemble leaves and stems. They have rhizoids for absorbing water and anchoring the plant to substratum. Life cycle consists of two morphologically different plants, the gametophyte and sporophyte. The two alternate. They show alternation of generations. The gamete producing gametophyte is the persistent plant. The sporophyte is attached to the gametophyte and is nutritionally dependent on it. They lack vascular system. Sexual reproduction is dependent on water. Division Pteridophyta:
These include ferns and horsetails. General Characteristics
They have root and shoot system. Leaves are compound known as fronds, they have a vascular system. They show alternation of generations whereby the spore bearing sporophyte is the main plant. Spores are borne in clusters on the underside of leaves making sari. The gametophyte is an independent minute structure called prothallus which is short lived. Sexual reproduction is dependent on water. Division Spermatophyta
These are the seed bearing plants. General Characteristics
Plant body is differentiated into root, stem and leaves. Vascular tissue consists of xylem and phloem. Sexual reproduction is independent of water. Male gametophyte (pollen grain) germinates and grows to reach female gametophyte.
Vascular tissue consists of xylem and phloem. Sexual reproduction is independent of water. Male gametophyte (pollen grain) germinates and grows to reach female gametophyte. They are divided into two sub-divisions:
Gymnosperms
Angiosperms. Gymnosperms
These are cone-bearing plants. Naked seeds. They are trees and shrubs. Xylem consists of tracheids only. Examples; pine, cypress and spruce. They show xerophytic characteristics like having needle-like leaves. Angiosperms
Seeds are enclosed within a fruit. They comprise trees, shrubs and herbs. Xylem consists of vessels of tracheids. These are the most advanced plants. Angiosperms has two classes;
Monocotyledonae
Dicotyledonae. Comparison of Dicotyledonae and Monocotyledonae
Economic Importance of Spermatophyta
They are a source of food for humans and other animals. Source of fue1- wood fuel and charcoal. Source of timber for building and for paper. Ornamental plants. Useful in textile industry. Kingdom Animalia
Most animals move from place to place in search of food. Major phyla are:
Platyhelminthes (Tapeworm). Nematoda (Ascaris). Annelida (Earthworm). Mollusca (Snails). Arthropoda
chordata
Phylum Arthropoda
Distinguishing Characteristics
They have jointed appendages, which are specialised for various functions. Their body is covered by a hardened exoskeleton made of chitin. It is shed at intervals to allow for growth. They have jointed body parts. Most are divided into head, thorax and abdomen. Some have two body parts,
General Characteristics
Body is segmented. They have bilateral symmetry. Gaseous exchange is through tracheal system, book lungs or gills which opens to the outside through spiracles. Aquatic forms use gills. Reproduction is mainly sexual. They have an open circulatory system. Phylum Arthropoda divided into five classes;
Crustacea,
Arachnida,
Chilopoda,
Diplopoda
Insecta
This division is based on:
The number of limbs. Presence and number of antennae. Number of body parts.
Phylum Arthropoda divided into five classes;
Crustacea,
Arachnida,
Chilopoda,
Diplopoda
Insecta
This division is based on:
The number of limbs. Presence and number of antennae. Number of body parts. Class Crustacea
Most of them are aquatic, a few are terrestrial found in moist places e.g., woodlouse. Distinguishing Characteristics
Two body parts head and thorax are fused to form cephalothorax and an abdomen . They have two pairs of antennae; one is small and branched, the other is long. They have five or more parts of limbs. Some of these are modified for other functions e.g., locomotion, feeding and defence. Exoskeleton hardened with deposits of calcium carbonate i.e. carapace. Other Characteristics
Mouthparts include a pair of mandibles and two pairs of maxillae. Gaseous exchange is through gills. They have a pair of compound eyes. Most crustaceans are free-living but a few are parasitic e.g., barnacles. Examples are cray-fish and crab. Class Arachnida
Members are carnivorous and paralyse prey using poison produced from poison claws. Distinguishing Characteristics
The body has two parts: cephalothorax and abdomen. Cephalothorax is head fused to thorax. A pair of chelicerae, on ventral side of cephalothorax. They have four pairs of walking legs. They have no antennae. Instead they have a pair of short pedipalps which are sensitive to touch. Most arachnids use book lungs for gaseous exchange. Other characteristics include simple eyes. Examples include garden spider, ticks, scorpions. Class Chilopoda
e.g. Centipede
Distinguishing Characteristics
The body has 2 body parts, a head and trunk. The body is elongate, and has 15 or more segments. Has a pair of legs on each segment. The body is dorso-ventrally flattened. Other characteristics include:
Head has a pair of antennae. Gaseous exchange through tracheal system. Are carnivorous. Class Diplopoda e.g. Millipede
Distinguishing Characteristics
Has two parts: head, short thorax and a trunk . Body elongate with 9-100 segments. Has two pairs of legs on each segment.
Millipede
Distinguishing Characteristics
Has two parts: head, short thorax and a trunk . Body elongate with 9-100 segments. Has two pairs of legs on each segment. They have a cylindrical body. Gaseous exchange is by tracheal system. Other characteristics:
Head has a pair of antennae. Are herbivorous. Class Insecta
Distinguishing Characteristics
Body is divided into three body parts head, thorax and abdomen. They have three pairs of legs .. Most insects have a pair or two of wings. Other characteristics include:
A pair of antennae. They breathe through spiracles, and gaseous exchange is through tracheal system. The class is divided into several orders based on:
Mouth parts- - type e.g. biting or piercing. Position of mouthparts - ventral or anterior. Wings - presence or absence; number of wing types, structure, texture. Size of legs. Order Orthoptera
Have biting and chewing mouthparts. Hind legs longer than other legs e.g. fore wings, leathery and longer than hind legs . e.g. locusts and grasshoppers . Swarming - locusts are a menace to farmers and the environment as they destroy crops and vegetation. Order Diptera –
True flies e.g. houseflies, and mosquitoes have sucking and piercing mouthparts, 1 pair of wings. The second pair is vestigial- acts as balancer. Mouthparts are ventral. These are disease vectors e.g., female anopheles mosquito transmits malaria. Order Lepidoptera –
Butterflies and moths have sucking mouthparts,
Two pairs of wings covered by scales. This group is important to farmers in pollination. Order Hymenoptera –
Bees ,wasps, ants. They have sucking mouthparts, two pairs of wings which are membranous. Some are non-winged e.g. some ants. Bees are important in pollination i.e. in production of honey. Order Isoptera - Termites
They have biting mouthparts which are anterior. Most are wingless,
Those with wings they are membranous and of the same size. They are important in nutrient cycling as they feed on cellulose. Order Coleoptera - Beetles
Have biting mouthparts,
Two pairs of wings,
Fore wing hardened enclosing membranous wings.
Most are wingless,
Those with wings they are membranous and of the same size. They are important in nutrient cycling as they feed on cellulose. Order Coleoptera - Beetles
Have biting mouthparts,
Two pairs of wings,
Fore wing hardened enclosing membranous wings. Destruction of stored grains and legumes (pulses)
Phylum Chordata
This name is derived from the term notochord. This is a long flexible rod-like structure. The more familiar chordates are known as vertebrates. In vertebrates the notochord exists only in embryonic stages of development which in later stages is replaced by a vertebral column. Main Characteristics of Vertebrates
Members of the phylum have a notochord in early stages of development. They have visceral clefts - which are slits perforating the body wall at the pharynx. In fish these slits become gills while in higher chordates these slits are only present in embryo. They have a dorsal, hollow nerve cord. It develops into a brain at the anterior and spinal cord at the posterior end. The spinal cord is enclosed within the vertebral column. They have segmented muscle blocks known as myotomes on either side of the body. They possess a post-anal tail although rudimentary in some. They have a closed circulatory system. The heart is ventrally located. They possess an internal skeleton. The main classes of phylum chordata are;
Pisces,
Amphibia,
Reptilia,
Aves
Mammalia. Class Pisces
These are the fishes. Some fish have a skeleton made of cartilage e.g. the shark. Others like Tilapia have a bony skeleton. Distinguishing Characteristics
They are aquatic. Movement is by means of fins. They have a streamlined body. They have a lateral line for sensitivity. Their heart has two chambers, the auricle and ventricle - simple circulatory system. Other Characteristics
Their body temperature changes according to the temperature of the environment. They are ectothermic (poikilothermic). Body covered with scales. They have gills for gaseous exchange. Exhibit external fertilisation. Class Amphibia
Larval forms are aquatic while adults are terrestrial. Adults return to water for breeding e.g. frogs, toads, newts, salamanders. Distinguishing Characteristics
Skin is soft and without scales. They have four well developed limbs.
frogs, toads, newts, salamanders. Distinguishing Characteristics
Skin is soft and without scales. They have four well developed limbs. The hind limbs are longer and more muscular than forelimbs. The limb can be used for walking, jumping and swimming
Gaseous exchange is through the skin, gills and lungs. Middle ear is present. Other Characteristics
They have a three-chambered heart with two atria and one ventricle. Fertilisation is external. They are ectothermic (poikilotherms). Class Reptilia
Examples are snakes, crocodiles, lizards, chameleons, tortoises and turtles. Distinguishing Characteristics
The skin is dry and is covered by horny scales. Fertilisation is internal. Some species eggs contain a lot of yolk and have either leathery or calcareous shells. They have a double circulatory system. The heart has three chambers - two atria and a partly divided ventricle. However crocodiles have a four chamber heart. Other Characteristics
They are ectothermic (poikilothermic). Have 2 pairs of limbs. They use lungs for gaseous exchange. Class Aves
These are birds. They are terrestrial and arboreal and others are aquatic
e.g. flamingo, goose, ostrich, penguin, hawk, dove. Distinguishing Characteristics
Body is covered by feathers and legs with horny scales. They have two pairs of limbs. Fore limbs modified to form wings for flight. Hind limbs are for walking or swimming. The mouth is a protruding beak. They have hollow bones. They have double circulation with a four-chambered heart (2 atria, 2 ventricles). They have lungs for gaseous exchange. Lungs are connected to air sacs in bones. Fertilisation is internal. They lay eggs with calcareous brittle shell. They have constant body temperatures hence are homoiotherms (endothermic ). Class Mammalia
They are arboreal e.g. tree-squirrels,
Others terrestrial e.g. humans
Others are aquatic e.g. dolphins and whales. Distinguishing Characteristics
They have mammary glands hence name of the class. Body is covered with fur or hair. Their teeth are differentiated into four types (heterodont dentition). They have external ear-pinna. Most have sweat glands.