High School

1.4.4 Infertility is a permanent loss of fertility in bulls.
1.4.6 Embryo splitting is a process of treating a female with hormones in order to produce many ova at the same time.
1.4.6 Artificial Insemination takes place when the bull is allowed to mount and service a cow.
1.4.7 Eutocia is a condition of prolonged and difficult parturition.
1.4.8 Oestrogen is responsible for the maintenance of pregnancy and its level drops soon after birth.
1.4.9 The endoderm is the outer germ layer from which the external organs, mainly the skin, hooves and hair, develop.
1.4.10 Mating is the period between fertilisation and birth.
1.4.11 The method used to increase the number of identical offspring from a single embryo, is embryo flushing.
1.4.12 The endoderm is the layer from which the heart, skeleton, muscles, urogenital and vascular systems develop.
1.4.13 Posterior presentation is when the foetus lies on its abdomen with its forefeet and nose stretched towards the pelvis and head resting on its forefeet.
1.4.14 Vas deference is a muscular tissue tube which serves as a common canal for excretion of both semen and urine.
1.4.15 The part of the sperm cell that facilitates penetration into the ovum is called the mid-piece.
1.4.16 An ovum is the end product of the process of spermatogenesis.
1.4.17 The epididymis is a tube of muscular tissue and is the common excretory canal for urine and semen.
1.4.18 Prostrate gland is a pair of glands located along the urethra secreting fluids which cleanse and lubricates the urethra before ejaculation.
1.4.19 Sertoli cells are responsible for the production of testosterone in the male reproductive system.
1.4.20 Adrenalin is a hormone in bulls that enhances sexual desire which leads to copulation.
1.4.21 The condition where the vagina protrudes from the vulva resulting in sterility is called abortion.
1.4.22 Luteotrophic is the hormone in dairy cows that is secreted by the structure that develops in the ovary after the Graafian follicle bursts.
1.4.23 Graafian follicle develops in the ovary after ovulation at the position of the burst follicle.
1.4.24 Transpleritation is a technic used on female animals to make them come into heat approximately at the same time.
1.4.25 Artificial insemination is the removal of viable embryos (using a saline solution) from a superior donor cow.
1.4.26 Abortion is the termination of pregnancy without the visible loss of the foetus.
1.4.27 The recipient cow has superior genetic traits to produce the desired ova.
1.4.28 The pistolette is minute polyvinyl piece of equipment in which semen is stored for future use.
1.4.29 Dolly, the famous sheep, produced seven identical lambs through the process of Genetic modification.
1.4.30 Twin lams developing from a single zygote, are referred to as freemartin twins.

Answer :

Let's analyze and clarify some key concepts and definitions mentioned in the statements:

  1. Infertility in Bulls: Infertility refers to the inability of a bull to reproduce by natural means. It is not necessarily a permanent condition unless caused by irreversible factors.

  2. Embryo Splitting: This is a technique used in animal breeding to produce multiple embryos from a single fertilized egg. It involves manipulating the embryo in vitro to create genetically identical copies. However, treating a female with hormones to produce many ova is usually referred to as superovulation, not embryo splitting.

  3. Artificial Insemination: This is a process where semen is collected from a male animal and manually inserted into the reproductive tract of a female. It differs from natural mating as it does not involve the physical act of mounting.

  4. Eutocia: This term actually refers to normal, uncomplicated birth or parturition, rather than difficult births.

  5. Oestrogen and Pregnancy: Oestrogen is involved in regulating various reproductive processes, including the maintenance of pregnancy, but it is primarily progesterone that is responsible for maintaining pregnancy. Oestrogen levels decline after birth, not before.

  6. Germ Layers:

    • The endoderm is the innermost layer, and it gives rise to structures such as the digestive and respiratory systems.
    • The ectoderm is the outer layer, responsible for developing the skin, nervous system, and related structures.
  7. Mating: Mating is the act of copulation, not the period between fertilization and birth. That period is referred to as gestation.

  8. Embryo Flushing: This is a method used to collect embryos from a donor animal to increase the number of offspring from desirable genetic lines. It involves flushing the uterus with a fluid to retrieve embryos.

  9. Presentation of Foetus: The description of the foetus lying on its abdomen with forefeet and nose stretched towards the pelvis is a normal anterior presentation, not posterior.

  10. Vas Deferens: It's a muscular tube that transports sperm from the epididymis as part of the seminal pathway, not for urine excretion.

  11. Sperm Cell Structure: The part of the sperm cell that facilitates penetrating the ovum is called the acrosome, located at the head of the sperm, not the mid-piece.

  12. Sertoli Cells: These cells support and nourish developing sperm cells, but testosterone is produced by Leydig cells.

  13. Prostate Gland: There is only one prostate gland, not a pair, and it produces fluids that are part of semen.

  14. Adrenaline and Sexual Desire: Adrenaline is not responsible for sexual desire or copulation; it is involved in the body's fight-or-flight response. Hormones like testosterone influence sexual behavior.

  15. Ectopic Pregnancy and Abortion: An ectopic pregnancy is when an embryo develops outside the uterus, and abortion involves the termination of a pregnancy with the loss of the foetus.

  16. Genetic Modification and Dolly: Dolly the sheep was cloned using a technique called somatic cell nuclear transfer, not genetic modification to produce identical lambs.

Understanding the precise definitions and biological processes helps in comprehending reproductive techniques and organic functions accurately. These clarifications refine the terms to reflect accurate biological concepts.