general zoology 210-05 exam 2 Flashcards
reproduction: define diploid and haploid.
- haploid: have 1 set of chromosomes, under meiosis
-diploid: have 2 sets if chromosomes, undergo mitosis,
reproduction: how many sets of chromosomes do gametes have?
-gametes have 1 set of chromosomes ( 23)
reproduction: explain spermatogenesis. where does spermatogenesis take place? what are the results of meiosis?
-spermatogenesis: spermatogonia will undergo
mitosis to produce primary spermatocytes
-made in the testis
-1 spermatocyte →4 spermatids
-primary spermatocyte (Diploid) to 2 haploid secondary spermatocytes (Meiosis I)
-Each secondary spermatocyte to
additional haploid spermatids
(Meiosis II)
reproduction: does temperature impact spermatogenesis?
yes
reproduction: explain oogenesis. Where does oogenesis take place? What are the results of meiosis?
-oogenesis: oogonia will undergo mitosis to produce primary oocytes
-made in the ovary
-1 oocyte→1 ovum
-primary oocyte (Diploid) to 2 haploid secondary oocytes (Meiosis I)
-the secondary oocyte will divide again (Meiosis II) into 1 ovum
reproduction: define oviparous
-oviparous: Egg laying –outside of the body, internal or external fertilization
- examples: invertebrates, egg laying
vertebrates
reproduction: define ovoviviparous
-ovoviviparous: fertilized egg will stay in the oviduct
or uterus until hatching, internal fertilization
-examples: invertebrates, fish, reptiles
reproduction: define viviparous
-viviparous: fertilized egg (without a shell)
develops in the oviduct or uterus, direct connection with developing embryo internally, internal fertilization
-examples: lizards, snakes, mammals, some
amphibians
reproduction: what is external fertilization?
external fertilization is when the egg gets fertilized by the sperm cell outside the body
reproduction: what is internal fertilization?
internal fertilization is when the egg gets fertilized by the sperm cell inside the body
reproduction: What is the SRY gene? What are some examples in the animal kingdom of how sex is determined?
-SRY gene: on Y chromosome
(male mammals)
-If not present (or activated) female default, hormone differences
(testosterone), leads to development of testes instead of the ovary
-incubation temperature (reptiles)
reproduction: what is the cloaca? ( female & male)
-cloaca: common chamber for all intestinal,
reproductive, and excretory products
-almost all vertebrates (except most
mammals), urogenital ducts open into a
cloaca
reproduction: seminiferous tubules (male)
-seminiferous tubules: a structure within the testes where sperm is made
-mammals testes descend into the
scrotum
reproduction: epididymis ( male)
-epididymis: where sperm is stored
reproduction: vas deferens (male)
-vas deferens transports sperm to
the urethra and out the penis
reproduction: what are the additional glands providing additional fluid to semen along the way ( male)
-prostate gland
-bulbourethral gland
- seminal vesicle
reproduction: urethra ( female & male)
- urethra: organ that secretes urine and other material within
reproduction: ovary
- ovary: source of the ova and sex hormones (estrogen
and progesterone)
reproduction: oviduct
-oviduct: where fertilization takes place (fallopian or uterine
tubes)
reproduction: uterus
-uterus: where the endometrium is, where embryo is resting
reproduction: placenta
- placenta: organ that will connect wall of uterus
to the embryonic membranes
reproduction: endometrium
- endometrium: a blood layer that builds up and sheds if there is no fetus, provides an extra layer of protection when internal fertilzation occurs
reproduction: uterine horn
uterine horn: less developed uterus and more developed uterine
horns for implantation
reproduction: vagina
- vagina: will receive the penis and
serve as the birth canal
development: what is radial cleavage?
radial cleavage: upper cells are on top of lower
cells
development: what is spiral cleavage?
spiral cleavage: upper cells are packed in between
the lower cells
development: what is blastulation? what is the blastocoel?
- blastula: cleavage continues until the blastula stage (cluster of cells)
- blastocoel: forms a layer around a fluid filled cavity
development: what is gastrulation? how is this related to the ectoderm and endoderm germ layers?
- gastrulation: blastula into a 2-3 germ layer embryo
- germ layers ( diploblastic) is created during gastrulation
development: how does being diploblastic versus triploblastic play a role in the formation of the coelom?
-diploblastic: has 2 germ layers, endoderm and ectoderm, cavity is an upside down U
-triploblastic: has 3 germ layers, endoderm mesoderm and ectoderm, can form the coelom (empty cavity surrounded by
mesoderm)