Topic 6: Animal Reproduction and Development pt 1

Question 1

Asexual reproduction

Answer 1

Generation of new individuals without the fusion of the egg and sperm.

Question 2

Sexual reproduction

Answer 2

Generation of new individuals through the fusion of haploid gametes.

Question 3

what are Eggs (ova) and sperm compare their size and motility.

Answer 3

eggs: female gamete, large and nonmotile. sperm: male gamete, smaller and motile.

Question 4

zygote

Answer 4

a diploid cell from the fusion of egg and sperm

Question 5

is the majority of the human lifecycle diploid or haploid?

Answer 5

Diploid , only gametes are haploid.

Question 6

What are the 3 modes of asexual reproduction, describe them and examples of animals that do each

Answer 6

Fission: animal breaks into 2 equally sized individuals. ex: sea anemone Budding: large parent produces outgrowths which breaks off from the main body. ex: stony corals. Fragmentation: individual disintegrates into many small pieces which grow back into a full-sized, functional individuals. ex: annelid worms, sponges, cnidarians tunicates, flatworms.

Question 7

Difference between offspring in sexual and asexual reproduction

Answer 7

In asexual repro. offspring are genetic clones, sexual repro. genetic variation.

Question 8

what’s parthenogenesis

Answer 8

A form of asexual reproduction that uses the reproductive tract of the female, and an egg produces offspring without fertilization (so no sperm).

Question 9

Parthenogenesis progeny can be haploid or diploid true or false, explain

Answer 9

true if not fertilized the offspring are haploid, if fertilized the offspring are diploid.

Question 10

Hermaphorditism

Answer 10

Individuals have both male and female reproductive systems. So any two individuals can mate with eachother.

in humans we call it intersex

Question 11

what’s a drawback to sexual reproduction

Answer 11

energetically expensive

Question 12

whats Monoecious, examples of animals that are?

Answer 12

both gametes/gonads within same body ex: barnacles, clams, tapeworms

mono=one like one body

Question 13

whats Dioecious

Answer 13

only one type of reproductive system in the body

Question 14

What’s protandry and protogyny in hermaphordites

Answer 14

Protandry: means they develop male organs first, protogyny means they develop female organs first

think gyny like gynocologist (so female)

Question 15

what adaptations have allowed animals to overcome the limitation of finding a mate being energetically expensive

Answer 15

Hermaphorditism, and Harems

Question 16

what are Harems?

Answer 16

Groups of 1 male to many females.

common in aquatic animals

Question 17

Explain sex reversal in the bluehead wrasse fish harems. Why does it happen

Answer 17

When the 1 male dies, a female (usually the largest and oldest) will get male gonads to ensure enough males in the population to protect and defend the harem.

Question 18

fill in the blank

Most sexual animals have reproductive cycles that correspond to__

Answer 18

various changes in the environment. ex: mating seasons ensurs that there will be enough food when offspring is born.

Question 19

Fill in the blanks

Sexual animals reproductive cycles are usually controlled by _ which are regulated by __

Answer 19

hormones, environmental cues.

Question 20

what can disrupt and reduce reproductive cycles? (especially in nothern/artic species). example?

Answer 20

Climate change. Ex: Caribou migrate to calving grounds in the spring, which have high food availibility due to all the plants. But increasing temperatures mean plants arrive earlier so when calves are born, the plants are too far developed and hard for them to digest.

Question 21

what are the advantages of asexual reproduction

Answer 21

Allows for favourable genotypes to remain in the population for a long time. Energetically less expensive. Maintains high population size.

Question 22

Advantages of Sexual reproduction

Answer 22

Increases genetic variation which may allow offspring to survive in less ideal environments. Genetic recombination allows for adaptation. Allows the population to reduce deleterious mutations.

Question 23

Fertilization

Answer 23

brings eggs and sperm together to form zygote

Question 24

what is Internal fertilization? what does it require? what’s an advantage of it

Answer 24

sperm is deposited in or near the female reproductive tract. Requires coordinated mating behaviours and systems. Advantages: keeps gametes safe and viable.

Question 25

what is External fertilization? what does it require and why?

Answer 25

females release eggs into the environment to be fertilized by sperm that is also released. Requires moist habitats to prevent dehydration and so sperm can swim.

Question 26

describe spawning (type of external fertilization)

Answer 26

individuals are clustered together and release gametes at the same time.

Question 27

what can stimulate the release of gametes in external fertilization? examples?

Answer 27

Chemical/behavioural cues. Ex: female frogs will release eggs only when male clasps her during mating behaviours. pheromones can also affect individual behaviour to stimulate mating (like in moths). ## Footnote Ensure that the opposite gamete is nearby for fertilization to occur.

Question 28

Which produces fewer gametes internal or external fertilization

Answer 28

internal (less space)

Question 29

How are offspring of egg-laying animals protected as they develop

Answer 29

Eggs have hard calcified shells and internal membranes

Question 30

how are marsupials offspring protected as they develop

Answer 30

embryos reside in the pouch, spending only a short time in the uterus of the female.

Question 31

when are gametes established in embryonic development

Answer 31

early, but remain inactive until individual is sexually mature.

Question 32

How do animals that lack gonads produce gametes? Ex of animal

Answer 32

Gametes are produced directly from undifferentiated cells lining the coelom, where they mature and are released into the coelom. Ex: polychaete worms in annelida.

Question 33

How do animals with accessory tubes and glands as their reproductive system produce gametes? Ex of animal?

Answer 33

Males have testes that produce and store sperm until ejaculation. Females receive sperm in the spermathecae (sacs), which can store sperm for days to years until the female releases the sperm to fertilize the eggs. Ex: insects.

Question 34

Reproductive tracts in vertebrates are highly varied describe females variations. (Mammals vs non mammals and marsupials)

Answer 34

Most have 2 ovaries. Humans have 1 uterus but many mammals have 2. Number of openings can vary among animals. Many non mammalian vertebrates have a cloaca (one opening for digestive, excretory and reproduction). Marsupials have 3 openings (one for each uterus and 1 birth canal).

Question 35

Reproductive tracts in vertebrates are highly varied describe males variations. (In fish, reptiles)

Answer 35

Mainly differ in copulatory organs. Fish just release sperm into the environment but some have modified pelvic fins to form a channel for sperm transfer. Most reptiles release sperm from the cloaca. Some have penis like structures that are inserted into the female reproductive tract.

Question 36

Animals usually mate with more than 1 partner what is this called

Answer 36

Polygamy

Question 37

What’s monogamy examples of animals that do this

Answer 37

Relatively rare among animals, including most mammals. Ex: Canada geese and wolves “mate for life”. Males and females have adaptations that reduce the chance of other partners succeeding with the mating following (like chemical pheromones)

Question 38

The male reproductive system includes two main anatomies describe them:

Answer 38

External: scrotum and penis Internal: gonads, accessory glands, and ducts

Question 39

What are the male gonads

Answer 39

The testes

Question 40

Where in the testes are sperm produced (spermatogenesis)

Answer 40

In highly coiled seminiferous tubules.

Question 41

What 2 parts are contained in the testicle

Answer 41

The testis and the scrotum

Question 42

Why is the testis external

Answer 42

To maintain its temperature 2 degrees cooler than core body temp, sperm can’t be too hot

Question 43

What are the 3 sets of accessory glands in the male reproductive system

Answer 43

Seminal vesicles, prostate gland and bulbourethral glands

Question 44

Describe what the seminal vesicles produce

Answer 44

produces 60% of the semen volume; yellowish, thick and alkaline.

Question 45

Describe what the prostate produces

Answer 45

Thin, milky fluid containing anticoagulant enzymes and citrate secreted directly into the urethra.

Question 46

Describe what the bulbourethral glands produce

Answer 46

Fluid to neutralize any acid urine prior to ejaculation, below the prostate.

Question 47

What’s Spermatogenesis. When does it occur?

Answer 47

The formation and development of sperm, continuous and occurs throughout adolescence and adulthood.

Question 48

How many sperm cells are produced daily, how many weeks does it take per sperm cell to complete

Answer 48

100s of millions produced daily, takes 7 weeks per sperm cell to complete.

Question 49

Each of the four daughter cells produced by meiosis produce a

Answer 49

Viable sperm

Question 50

Acrosome

Answer 50

Contains enzymes to help sperm penetrate the egg

Question 52

What is the starting cell called in spermatogenesis

Answer 52

Spermatogonial stem cell

Question 53

in spermatogenesis Whats the cell called after two mitotic divisions, at the start of meiosis 1.

Answer 53

Primary spermatocyte

Question 54

What’s the first haploid cell called in spermatogenesis

Answer 54

Secondary spermatocyte (after meiosis 1)

Question 55

What is the head of the sperm called, what is on the tip of the head

Answer 55

The haploid nucleus, on the tip is the acrosome

Question 56

What does the mid piece of the sperm contain

Answer 56

The mitochondria

Question 57

What is the tail of the sperm for

Answer 57

Movement

Question 58

What are the two main anatomies of the female reproductive system

Answer 58

External: clitoris, and two sets of labia Internal: gonads, ducts, and chambers

Question 59

Describe the Ovaries

Answer 59

Female gonads, flank the uterus and held in place by ligaments. Outer layer is packed with follicles, each containing a oocyte (egg)

Question 60

Oviducts (fallopian tubes)

Answer 60

Connect the ovaries to the uterus diameter as thin as human hair. During ovulation the egg is released in the oviduct and is transported through cilia lining the tube.

Question 61

Uterus, cervix?

Answer 61

Thick muscular organ, inner lining is endometrium, supplied with tons of blood vessels the neck of the uterus is the cervix, which opens to the vagina.

Question 62

Oogenesis

Answer 62

The formation and development of eggs (ova), prolonged and interrupted in females. Immature oocytes form in the uterus before birth of the fetus but do not complete development until sexual maturity is reached.

Question 63

How many of the daughter cells produced in meiosis become a mature gamete in oogenesis

Answer 63

Only 1 out of 4 due to unequal cytokinesis. The others get destroyed.

Question 64

What is the starting cell of oogenesis called

Answer 64

Oogoniun

Question 65

What is the first haploid cell in oogenesis

Answer 65

The secondary oocyte

Question 66

what hormone at puberty stimulates a small group of follicles to resume growth and development

Answer 66

Follicle stimulating hormone (FSH), usually 1 follicle per month.

Question 67

Completion of meiosis 2 only occurs if

Answer 67

the sperm penetrates the secondary oocyte

Question 68

What happens to the ruptured follicle after the secondary ooctye is released during ovulation

Answer 68

It develops into the corpus luteum, which will degenerate unless the egg is fertilized.