Cell & animal reproduction

1. Cell & animal reproduction Grade 6 Compiled by: Alya Kays

2. Plants reproduction

4. Animal Cell • The body is made up of millions of tiny cells • Most of the cell is made up of protoplasm • Cell parts: • Nucleus • Cytoplasm • Cell membrane

5. Nucleus Cytoplasm Cell Membrane Animal Cell

6. SHAPE • Plant cell is rectangular in shape. • Animal cell is spherical in shape.

7. Plant cells Animalcells

8. CELL WALL • Plant cell is covered by a thick cell wall. • Cell wall is made up of cellulose and hemicellulose. • Animal cell is covered by a thin cell membrane. • It is made up of Lipoprotein.

9. VACUOLE • In plant cell, Vacuole is big, prominent and permanent.

10. Vacuole • In animal cell, Vacuole is small, temporary and not so prominent.

11. PLASTIDS • Plastids are present only in plant cell. • Plastids are of three types. • *Leucoplast • *Chromoplast • *Chloroplast • PLASTID IS ABSENT IN ANIMAL CELL.

12. Paramecium

13. Red blood cells • Erythrocytes, or red blood cells, are the primary carriers of oxygen to the cells and tissues of the body. The biconcave shape of the erythrocyte is an adaptation for maximizing the surface area across which oxygen is exchanged for carbon dioxide. Its shape and flexible plasma membrane allow the erythrocyte to penetrate the smallest of capillaries.

14. Human smooth muscle, also referred to as visceral or involuntary muscle, is composed of slender, spindle-shaped cells. Controlled by the autonomic nervous system, smooth muscle cells help form the structure of the skin, blood vessels, and internal organs.

15. Cardiac muscle is a unique muscle tissue found only in the heart. Requiring a constant supply of oxygen, cardiac muscle will quickly die if obstructions occur in the arteries leading to the heart. Heart attacks occur from the damage caused by insufficient blood supply to cardiac muscle.

16. Skeletal muscles attach to bones. They help you do things such as kick a ball, chew food, or write. When one of these muscles contracts, or shortens, the bone attached to the muscle moves. Skeletal muscles are voluntary—that is, you control when they work. Skeletal muscles consist of cells containing light and dark bands that make them appear striped.

17. Nerve cell: This photomicrograph shows a number of multipolar nerve cells. The central cell body is clearly visible in each of the cells, as are the dendrites. The dendrites are short extensions of the nerve cell body that function in the reception of stimuli.

18. Epithelial Cells • The epithelium is a protective layer of cells that covers an organ surface or lines a body cavity. Shown here is a layer of simple squamous (scaly) epithelium. Skin is composed of several layers of epithelial cells.

19. Bone cell Osteocytes

21. Cell Division • Mitosis • Increases total number of cells • Results in animal growth • Chromosomes pairs are duplicated

22. Cell Division • Meiosis • Produces gametes • Only have one-half the chromosomes of normal cells

23. Gametes

26. Reproductive Terminology • Species Act Offspring • Cows calving calf • Ewes lambing lamb • Sows farrowing pig • Hens hatching chick • Mares foaling foal • Goats kidding kid • Frog hatching tadpole

27. Mammals Reproduction Objective: Specify how the reproductive system for mammals functions

28. Terminology • Estrus • When a female is receptive to be bred • Lactation • Period of time that milk is secreted by the mammary glands • Parturition • Than act of giving birth

29. Reproductive Functions of the Female Estrous cycle - time from one heat period (or menstrual cycle) to the next. Length of estrous cycle by species: Cow 19 - 21 days Ewe 16 - 17 days Sow 19 - 21 days Mare 21 - 24 days Woman 28 days Hen none

30. Female Tract

31. Female Reproductive System • Ovary - the ovary is comparable to the male testicle and is the site of gamete production. • A bovine animal has 20,000 potential eggs per ovary, while a human female has 400,000 potential eggs per ovary. • Ova are fully developed at puberty and are not continuously produced as in the male. • All species contain two functional ovaries except for the hen which has only a left functioning ovary.

32. Female Reproductive System • Uterine Horn- The anterior, divided end of the uterus in the cow, ewe, and mare. Sow has only 2 horns, no body, woman has no horns, only body. • Uterus - Muscular sac connecting fallopian tubes and cervix 1. Sustains the sperm and aids in its transport 2. Supports embryo and fetus during gestation 3. Expels fetus at parturition

33. Female Reproductive System

34. Reproductive Functions (Female) Steps in the female reproductive process: 1. Ovulation • Produce gamete (ova or ovum) • Release of egg(s) • Infundibulum pushes the ovum into the fallopian tube

35. Ovulation Rates Ovulation Rates by Species Cow- 1 egg per estrus Ewe- 1 to 3 eggs per estrus Sow- 10 to 20 eggs per estrus Mare- 1 egg per estrus Hen- Approx. 28 eggs per month

36. Fertilization • When the sperm from a male reaches the egg from a female • Two cells join to form a complete cell • Pairs of chromosomes are formed again • Many different combinations of traits are formed

37. Fertilization

38. Figure 16.13 Fertilization

39. Reproductive Functions (Female) Gestation and Lactation Periods: Species Gestation Period Lactation(Milking) Cow 275 - 285 days beef 180 - 270 days dairy 305 - 365 days Ewe 115 - 142 days 60 - 90 - 120 days Sow 112 - 115 days 21 - 42 days Mare 330 - 345 days 90 - 150 days Woman 270 days ? years

41. Baby development

42. Human baby

44. Birds Reproduction in Poultry Objective: Specify how the reproductive system for poultry functions

46. Reproduction in Poultry The poultry oviduct has five parts: 1) Vagina • Holds the egg until laid 2) Uterus • Secretes the shell 3) Isthmus • Adds the two shell membranes 4) Magnum • Secretes the albumen 5) Infundibulum • Where fertilization takes place

50. Reproduction in Poultry • Major difference: • Embryo of livestock develop inside the female’s body while the embryo of poultry develops inside the egg. • Poultry only have the left ovary and oviduct when mature • The yoke is the ovum • Chicken Incubation • 21 days