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Flashcards in Animal development Deck (39)
1

parthenogenesis

asexual reproduction in which an egg develops without being fertilized

2

ovaries

female gonads; contains follicles which contains eggs

3

follicle

in the ovary; consists of one egg cell surrounded by one or more layers of follicle cells

4

oviduct

egg cell is realeased into this tube and travels to uterus

5

testes

male gonads; sperm forms in seminiferous tubules inside testes

6

epididymis

tubules where sperm passes and pushed through vas deferens duct

7

urethra

duct that drains both excretory and reproductive system

8

oogenesis

secondary oocyte can become the ovum; other 3 products of meiosis becomes polar bodies

9

FSH

follicle stimulating hormone; induces primary oocyte to undergo meiosis to metaphase II

10

ovulation

secondary oocyte is released at metaphase II and stays until sperm penetrates oocyte

11

menstrual cycle

endometrium increases with progesterone and estrogen release

12

estrous sycle

endometrium is reabsorbed without bleeding and animals are in heat

13

organogenesis

first trimester is main period of body organ development

14

acrosome

specialized vesicle at the tip of the sperm discharges hydrolytic enzymes which penetrates the jelly coat of egg

15

acrosomal process

actin filaments grow from sperm and contact egg cell receptors on vitelline layer

16

polyspermy fast block

fusion of sperm and egg membrane causes depolarization and produces fast block to multiple sperm entry

17

cortical reaction

slow block to polyspermy; fertilization envelope from cortical granules and hardening of vitelline layer

18

zona pellucida

in mammals this is hardened during cortical reaction

19

morula

first 5-7 divisions for a multicellular ball surrounded by fertilization envelope

20

blastula

avian; at least 128 cells with blastocoel in animal pole and yolk in vegetal pole

21

meroblastic cleavage

incomplete cleavage of yolk and embryo in avian egg

22

avian epiblast/hypoblast

avian version of a blastula and surrounds the blastocoel

23

gastrula

three germ layers of the embryo

24

archenteron

invagination at the blastopore; is the primitive gut with 2 openings

25

epiblast

all the cells that will form the embryo come from this layer

26

primitive streak

cells from epiblast form each of the 3 germ layers

27

notochord

formed from dorsal mesodermthat condenses just above the archenteron and is present in all chrodates

28

neural tube

from ectoderm; becomes central nervous system; rolled in from neural plate

29

neural crest

only vertebrates; forms peripheral nerves, teeth, skull bones, and other cells

30

holoblastic cleavage

mammals and others such as sea urchins; complete division of eggs having little yolk or moderate such as frogs

31

ectoderm

epidermis of skin, epithelium of mouth/rectum, cornea, nervous system

32

mesoderm

notochord, skeletal, muscular, excretory, circulatory, and reproductive system, lining of body cavity

33

endoderm

epithelial of digestive, excretory, reproductive, and respiratory system, pancreas, liver, thymus

34

blasctocyst

mammalian version of the blastula with an inner cell mass that becomes embryo and most of extraembryonic

35

trophoblast

outer layer of the blastocyst that initiates endometrium implantation

36

mammalian epiblast

similar to avian, embryo almost entirely develops from epiblast cells

37

chorion

completely surrounds embryo and other extraembryonic membranes and functions gas exchange

38

allantois

incorporated into the umbilical cord and forms blood vessels with placenta

39

cadherins

class of cell adhesion molecule that requires calcium ions for proper function