Physics Chapter 17 What Allantois Where Found And What Purpose

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Pregnancy, Development, and Lactation

PREGNANCY

EXERCISE 1. IDENTIFY THE OVARIAN CYCLE

4 Ovulation (ruptured follicle)

EXERCISE 2. IDENTIFY THE UTERINE LAYERS

2 High progesterone levels keep this layer quiet

1 The blastocyte embeds here

1 The mucous membranes and blood vessels of this layer

enlarge during pregnancy

EXERCISE 3. MATCH THE TYPES OF PLACENTAL

ATTACHMENT

TYPE OF ATTACHMENT

Discoid 3, 5, 12, 15

EXERCISE 4. IDENTIFY THE TYPE OF

PLACENTAL ATTACHMENT

A. Cotyledonary

DEVELOPMENT

EXERCISE 5. CLINICAL THINKING CHALLENGE

#1: CLIENT EDUCATION

A dog’s pregnancy lasts about 3 months while a human’s

belly? If your doggie is throwing up a bit, that is also a sign

of pregnancy, called morning sickness. Don’t get upset if

she doesn’t want to eat much, that’s normal for the end of

signs of restlessness and a need for privacy (secrecy)—and

pretty soon you will have several new puppies to care for.

LACTATION

EXERCISE 6. DEFINE LACTATION TERMS

1. Milk let-down is the immediate effect of nursing or milking.

lactation gradually to cease. The mammary gland “dries up.”

3. Colostrum Before it starts to produce milk, the mammary

gland produces a sort of premilk secretion called colostrum.

4 . M e c o n i u m is the dark, sticky contents of a newborn’s

intestinal tract.

HORMONE SOURCE

Breeding Estrogens

Parturition Relaxin

ACTH

Glucocorticoids

Estrogens

Prostaglandin

F-alpha

Oxytocin

Placenta

Anterior pituitary (fetus)

Adrenal glands (fetus)

Placenta

Placenta & Uterine wall (dam)

Posterior pituitary (dam)

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CHAPTER 17 Pregnancy, Development, and Lactation

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EXERCISE 8. CLINICAL THINKING CHALLENGE

#2: NAME THE OFFSPRING

SPECIES OFFSPRING

Alpaca Cria

Ass/donkey Foal

Camel Calf

EXERCISE 9. CLINICAL THINKING CHALLENGE

#3: EXPLAIN THE PROCESSES IN THE

REPRODUCTIVE CYCLE

1 . When is the full genetic map for the new animal

established? Once an ovum is fertilized, it gets a name

change and becomes known as a zygote. Immediately

2 . What happens in cleavage? As soon as the two pronuclei

join to form a single nucleus, each chromosome makes a

copy of itself, and the zygote begins to divide rapidly by

the normal process of mitosis. This rapid division is

The number of cells making up the zygote is increasing

dramatically, but its overall size is still about the same as

the original ovum, even after several days.

3 . What is allantois, where is it found, and what purpose

does it serve? The fetus ﬂ oats in amniotic ﬂ uid inside the

amniotic sac. Surrounding the amniotic sac is another

layer called the allantois, which forms the ﬂ uid-ﬁ lled

sists of the actual delivery of the newborn. This is

accomplished by a combination of strong uterine and

abdominal muscle contractions. Rupture of the “water

bags,” the amniotic and allantoic sacs of the placenta,

usually precedes the actual delivery of the newborn. The

third stage of labor consists of delivery of the placenta

(afterbirth). The placenta separates from the wall of the

9 . Describe involution of the uterus. After parturition is com-

plete, the uterus immediately begins contracting down to its

nonpregnant size through a process called involution of the

uterus. At the placental attachment site(s), the endome-

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CHAPTER 17 Pregnancy, Development, and Lactation

its nonpregnant size. Initially the discharge contains fresh

blood, resulting from separation of the placenta from its

attachment site(s). Pressure from the continued uterine

contractions usually stops the bleeding relatively quickly.

milk-secreting systems and ducts leading down to their

own teats.

1 1 . The udder of a high-producing dairy cow can weigh more

than 100 lb at milking time. Describe the anatomic support