8-1.Growth and development

1,156 views

Published on

Chapter 1 Grade 8 Odd Semester

Published in: Education
0 Comments
3 Likes
Statistics
Notes
  • Be the first to comment

No Downloads
Views
Total views
1,156
On SlideShare
0
From Embeds
0
Number of Embeds
3
Actions
Shares
0
Downloads
29
Comments
0
Likes
3
Embeds 0
No embeds

No notes for slide

8-1.Growth and development

  1. 1. GROWTH andDEVELOPMENT Created By Alfi Msk_ A Biology Teacher of GIS JH
  2. 2. a. The Definition• Growth constitutes an increase process in size including increases in height, and weight. Growth is quantitative and irreversible in nature• Development is a process towards maturity. Development is qualitative in nature, meaning that it is immeasurable Created By Alfi Msk_ A Biology Teacher of GIS JH
  3. 3. b. GROWTH and DEVELOPMENT in THE PLANTS• Plant growth occurs because of the size increase which is caused by the increase in the number of cells through cell division (mitosis) in the growing points and enlargement in each cell• Cell division mostly occurs in the meristem tissue, that mostly found in the root tip and stem tip which are called apical meristem Created By Alfi Msk_ A Biology Teacher of GIS JH
  4. 4. • When the young plants grow, the root and the stem grow longer, this growth is called primary growth• Some plants, such as wooden plants, have stems and roots which become thicker, this growth is called secondary growth• To measure the speed growth of plants, we use the auxanometer Created By Alfi Msk_ A Biology Teacher of GIS JH
  5. 5. • The development of seed plants which reproduce through the generative method starts with a zygote• The zygote grows into embryo then become an individual which posseses roots, stems, and leaves.• After reaching a certain age, the plants will produce flowers and seeds• The changes of shape and function from one zygote until the plant is forming root, stem and leaf organ is called the development process of plants Created By Alfi Msk_ A Biology Teacher of GIS JH
  6. 6. Factors Which Affect Plants Growth And Development• Internal Factors a. Genes - the size and shape of plants are affected by the genes inside the chromosomes - Chromosomes are found in the nucleus - Genes are derived from the parents - Genes control the growth pattern of the plants Created By Alfi Msk_ A Biology Teacher of GIS JH
  7. 7. b. Hormones - A hormones is a chemical subtance which is produced by plants, are often called growth subtances - Its function is to control the growth process - the common growth hormones are auxin, cytokinin, and gibberellin Created By Alfi Msk_ A Biology Teacher of GIS JH
  8. 8. 1. Auxin- Auxin is produced in the stem tip (bud), young leaves,flowers, fruit, and root tip- Auxin which found in the stem tip can inhibit thegrowth of branches, this condition is called apicaldominance. Therefore the plants can grow tall andstraight.- The effects of auxin are : to stimulate the lateral roots and fibrous roots growth to stimulate the growth of stem cells and inhibit thegrowth of root cells to stimulate the forming of flowers and fruit to speed up the cell division in Teacher of Created By Alfi Msk_ A Biology growing points GIS JH
  9. 9. 2. Cytokinin- Cytokinin is produced by plants in the root and then transported to the other organs- The role of cytokinin are : influencing the growth of the root stimulating cell division retarding the aging of plant organs (leaf, flower, and fruit) controlling the forming of flowers and fruit Created By Alfi Msk_ A Biology Teacher of GIS JH
  10. 10. 3. Gibberellin- Gibberellin is produced by the plants in the root meristem tissue, stem meristem, and young leaves- The role of gibberellin are : stimulating the growth and development of embryos and sprouts causing massive growth in plantsProducing big and seedless fruit (parthenocarpy) stimulating the forming of flowers Created By Alfi Msk_ A Biology Teacher of GIS JH
  11. 11. • External Factorsa. Water and Minerals - water and minerals are absorbed from the soil by the roots. - the minerals required by plants are carbon, oxygen, hydrogen, nitrogen, sulphur, phosporus, calcium, potassium, and magnesium. They are absorbed in form of ions that dissolved in the water. - water not only serves as a solvent but is also required for photosynthesis Created By Alfi Msk_ A Biology Teacher of GIS JH
  12. 12. b. Temperatures - temperatures influences the work of enzymes - a temperatures which is too low or too high will disrupt the work of enzymes, so it will inhibit plant growth and development - Every plant has the minimun, optimum, and maximum temperature to grow - the lowest temperature that still enables plants to grow and develop is called the minimum temperature - the most suitable temperature for plant growth and development is called the optimum temperature - the highest temperature that still enables the plants to grow and develop is called the maximum temperature Created By Alfi Msk_ A Biology Teacher of GIS JH
  13. 13. c. Humidity - an environment with low humidity will increase the evaporation (transpiration) of plant so that the water and mineral absorption from the soil will become more frequent, this will increase the speed of plant growth Created By Alfi Msk_ A Biology Teacher of GIS JH
  14. 14. d. Light Intensity - sunlight is highly required by plants for photosynthesis, this process produces food that is required for growth - the light can also influence auxin hormone, it will break down if it is exposed to sunlight - for example, a sprout that is exposed to light will slowly grow, while the sprout which put in a dark place will grow faster - the faster growth in darkness is called etiolation Created By Alfi Msk_ A Biology Teacher of GIS JH
  15. 15. c. GROWTH and DEVELOPMENT in ANIMALS and HUMANS• Growth and development in animals and humans occurs in all parts of the body, different from those of plants which only occur in certain parts.• Growth and development in animals and humans begin at the formation of the zygote• One zygote will grow and develop until an embryo is formed• In that particular stage, the embryo cells will differentiate to form various tissues and develop into fetus• The fetus will be born as a baby which then grow and develop into a toddler, adolescent, and then a adult Created By Alfi Msk_ A Biology Teacher of GIS JH
  16. 16. 2 phases in animals/humans’ growth and development• Embryonic phase Is phase started with the establishing of zygote up to embryo. Fertilization is a process in which a fusion of the sperm and ovum gamete occurs.• Post-embryonic phase Is phase after the embryo is formed. in animals, post embryonic is only a change in size, namely an increase in size of body parts. Created By Alfi Msk_ A Biology Teacher of GIS JH
  17. 17. Factors that Affect Animals Growth and Developmenta. Genes - a gene is a hereditary factor inherited by the parents - genes will determine and control the basic patterns of growth and development of an organismb. Hormones - hormones are secreted by endocrine glands - the hormone which has the main role in human or animal growth is the growth hormone (GH/Somatotropin) - people who are lacking somatotropin will undergo stunted growth, while those with an excessive amount of somatotropin will undergo GIS A Biology Teacher of Created By Alfi Msk_ gigantic growth JH
  18. 18. c. Food - one of characteristics of living organism is the need for food - the most important roles of food is to construct the body and as a source of energy. - the food subtance which has the biggest role in growth is proteind. Water - water is a solvent and a media for chemical reactions in the body - the chemical reactions will produce energy, help the forming of new cells, and repair damaged body tissues Created By Alfi Msk_ A Biology Teacher of GIS JH
  19. 19. e. Activity - physical activity which is done for years will affect the structures of bones and muscles - for example, body builders or runners, they possess good body posture and muscles. - people who do less physical activity wil possess weaker muscles and they will not properly develop.f. Sunlight - sunlight can alter provitamin D in the body into vitamin D which is needed in the growth of bone - lack of vitamin DCreated By Alfi Msk_ A Biology Teacher of can cause rickets during childhood GIS JH
  20. 20. d. THE STAGE of HUMAN GROWTH• Human growth and develoment begin from a very small ovum cell• The ovum is fertilized by sperm and the two nuclei will then fuse to form a zygote• A zygote will cleavage and become morulla• A morulla is developed become blastula through blastulation• A blastula is developed become gastrula through gastrulation• A gastrula has 3 embrionic layer : ectoderm, mesoderm, and endoderm Created By Alfi Msk_ A Biology Teacher of GIS JH
  21. 21. • Ectoderm will diffrentiate become skin, hair, nervous system, and sense organ• Mesoderm will differentiate become muscles, skeleton, reproductive organ, transportation system, and excretion system• Endoderm will differentiate become digestive system, and respiratory system Created By Alfi Msk_ A Biology Teacher of GIS JH
  22. 22. Zygote MorulaBlastula Created By Alfi Msk_ A Biology Teacher of Gastrula GIS JH
  23. 23. 1. Baby Birth• After about 9 months of growing and developing inside the uterus, the baby is ready to be born• The baby, which has come out of the uterus is still connected to her mother by umbilical cord and the placenta• The umbilical cord and the placenta are then cut by the doctor or the midwife• At this stage, the physical connection between the mother and the baby is broken, so that the baby can no longer obtain food and oxygen from the mother• When the umbilical cord and the placenta are cut, the breathing organs will soon function, so that the baby can inhale the air, and usually it is marked by the first cry• The cry is also a sign that the baby is able to pump the respiratory air from the lungs to the heart By Alfi Msk_ A Biology Teacher of Created GIS JH
  24. 24. 2. THE TODDLER and CHILDREN• The neonatal period is the first day of a baby’s life until the age of four weeks• In this period, the baby is able to adapt to life outside the uterus, can start suckling at its mother’s breast, and organs like lungs, heart, and also excretion organs are already well functioning Created By Alfi Msk_ A Biology Teacher of GIS JH
  25. 25. 3. PUBERTY• Puberty begins at about age 9 to 14, this is the stage you are going through now• Girls’ puberty characteristics are shown in some physical changes ; - the developing of hip and breasts - the appearance of pubic hair - the developing of reproductive organs, is marked by the first menstruation (menarche) Created By Alfi Msk_ A Biology Teacher of GIS JH
  26. 26. • boys’ puberty characteristics are shown in some physical changes ; - the chest looks wider - facial hair and pubic hair appears - the voice change - the deloping of reproductive organs, is marked by the wet dream Created By Alfi Msk_ A Biology Teacher of GIS JH
  27. 27. 4. ADULT STAGE• In this stage, the growth of bones and muscles begin to stop so adults cannot grow taller• Human psychological condition becomes more stable than during adolescence• People start to think about getting married and producing offspring Created By Alfi Msk_ A Biology Teacher of GIS JH
  28. 28. 5. OLD AGE• The cell ability starts degenerating, this causes some physical changes• Like weaker bones, degenerating ability to breath, degenerating elasticity of veins, and also causes skin to wrinkle• But sufficient nutrients and regular exercise can inhibit aging Created By Alfi Msk_ A Biology Teacher of GIS JH
  29. 29. e. METAGENESIS and METAMORPHOSIS Created By Alfi Msk_ A Biology Teacher of GIS JH
  30. 30. METAGENESIS• Moss and ferns experience two development stage in hteir life span, the spore producing stage (sporophyte generation, asexual) and the gamete producing stage (gametophyte generation, sexual)• The alternation from sporophye to gametophyte or vice-versa is called metagenesis Created By Alfi Msk_ A Biology Teacher of GIS JH
  31. 31. Moss Metagenesis Created By Alfi Msk_ A Biology Teacher of GIS JH
  32. 32. Fern Metagenesis Spore Protalium Anteridium ArkegoniumSpermatozoid Ovum Zygote Fern Spore Created By Alfi Msk_ A Biology Teacher of GIS JH
  33. 33. Metamorphosis• Is the shape and structural alternation which occurs in animals, starting from the embryo stage to adult• Animal which undergo metamorphosis are insects and frogs• Metamorphosis is differentiated into two types ; the complete metamorphosis and the incomplete metamorphosis Created By Alfi Msk_ A Biology Teacher of GIS JH
  34. 34. Complete metamorphosis• The metamorphosis which passes the stages egg, larva, pupa, and adult (imago)• In metamorphosis, the increase of body size is a growth process, while the change of the body shape from egg to adult is development process• For example, butterflies and frogs Created By Alfi Msk_ A Biology Teacher of GIS JH
  35. 35. FrogCreated By Alfi Msk_ A Biology Teacher of GIS JH
  36. 36. Created By Alfi Msk_ A Biology Teacher of GIS JH
  37. 37. Created By Alfi Msk_ A Biology Teacher of GIS JH
  38. 38. Created By Alfi Msk_ A Biology Teacher of GIS JH
  39. 39. ButterfliesCreated By Alfi Msk_ A Biology Teacher of GIS JH
  40. 40. FliesCreated By Alfi Msk_ A Biology Teacher of GIS JH
  41. 41. Incomplete Metamorphosis• Only passes the stages of egg, nymph (young animal), and imago ( adult animal)• No significant change of body shape occurs• For example, grasshoppers, cockroaches, and crickets Created By Alfi Msk_ A Biology Teacher of GIS JH
  42. 42. Created By Alfi Msk_ A Biology Teacher of GIS JH
  43. 43. Grasshopper Created By Alfi Msk_ A Biology Teacher of GIS JH
  44. 44. Created By Alfi Msk_ A Biology Teacher of GIS JH

×