meiosis, development and aging

Question 1

First cell that leads to development of a new individual is a fertilized ovum.

Answer 1

zygote

Question 2

Zygote is formed when a sperm cell forms a male and an oocyte (also called an egg cell) from a female join.

Answer 2

fertilization

Question 3

they are produced in the reproductive system

Answer 3

gametes
- oocyte
- sperm

Question 4

each reproductive have…

Answer 4

pair structures called gonads
tabular structures:
male - vas deferens
female - fallopian tube
hormones and secretion tht control the reproduction

Question 5

The seminiferous tubules are packed into paired, oval organs.

Answer 5

testes

Question 6

it bends behind the bladder and joins the urethra

Answer 6

ductus deferens
vas deferens

Question 7

it is a tube that carries the sperm and urine out of the body through the penis

Answer 7

urethra

Question 8

how many does the penis ejaculates and delivers

Answer 8

200 to 600 million sperm cells

Question 9

Female sex cells develop in paired organs in the abdomen.

Answer 9

ovaries

Question 10

Once a month, one ovary releases the most mature oocyte.

Answer 10

puberty

Question 11

muscular saclike organ

Answer 11

uterus or womb

Question 12

uterine tubes

Answer 12

aka fallopian tube
cilia sweeps the mature oocyte into the fingerlike projections of one of 2 uterine
carries oocyte inot the uterus

Question 13

A genetically overlord cell with more than 2 sets of chromosomes.

Answer 13

polypoid

Question 14

what are the 2 division of genetic material

Answer 14

reduction division (meiosis I)
- reduces the no. of replicated chromosomes from 46 to 23

equational division (meiosis II
- produces 4 cells from the 2 cells formed in the first division by splitting the replicated chromosomes

Question 15

The formation of sperm cells begins in diploid stem cells called a spermatogonium.

Answer 15

spermatogenesis

Question 16

why does the gametes of older people are more likely to have new mutations (that is, not inherited mutations) than the gametes of younger people

Answer 16

this happens because the cells go through more divisions and can accumulate more mistakes over time

Question 17

briefly explain the “paternal age effect” usually causes dominant single-gene diseases.

Answer 17

This refers to the fact that older fathers are more likely to pass on new mutations to their children, especially in genes that cause dominant single-gene diseases.

These are diseases where just one copy of a mutated gene (from one parent) is enough to cause the condition. This happens because sperm cells in older men divide more often, leading to mutations.

Question 18

parental development

Answer 18

index card

Question 19

Result from the fertilization of two separate
eggs with two different sperm during the
same pregnancy.

Answer 19

fraternal twins aka dizygotic twins

Question 20

a rare situation where two eggs from the same woman are fertilized by sperm from two different men during the same ovulation cycle. This happens when a woman releases two eggs and has sexual intercourse with two different men within a short period of time. As a result, she can become pregnant with twins that have different fathers.

Answer 20

Heteropaternal superfecundation

Question 22

how many days can a sperm and oocyte survive in a woman’s body

Answer 22

sperm - up to 3 days
oocyte - can be fertilized for the next 12 to 24 hours after ovulation (release of an egg cell)

Question 23

a process that chemically activates the sperm and the oocytes secrete a chemical that attracts the sperm

Answer 23

capacitation

Question 24

a week after fertilization, it nestles into the uterine lining

Answer 24

implantation

Question 25

after implantation, the outermost cells of the blastocyst is called? which secretes?

Answer 25

trophoblast
secretes hCG - human chorionic gonadotropin

Question 26

human chorionic gonadotropin

Answer 26

a hormone that prevents mensuration
defected in a woman’s urine or blood is one sign of pregnancy

Question 27

the cells that form the layers of the primordial
embryo

Answer 27

primary germ layers

Question 28

it is a stages of Primordial embryo which forms 3 layered curved, sandwich-like structure.

Answer 28

gastrula

Question 29

Listing structures involved in embryonic development

Answer 29

● Chorionic villi: Projections from the chorion that help form the placenta
● Placenta: Organ that develops during pregnancy to nourish the fetus
● Yolk sac: Provides early nourishment to the embryo
● Allantois: Helps in early blood formation and becomes part of the umbilical cord
● Umbilical cord: Connects the fetus to the placenta
● Amniotic sac: Fluid-filled sac that surrounds and protects the developing embryo/fetus

Question 30

true or false:
stem cells from umbilical cords can be manipulates to obtain and grow almost any cell type

Answer 30

true

Question 31

what are the 2 supportive structure develop during
pregnancy that provide material for prenatal
tests

Answer 31

Chorionic villus sampling
Amniocentesis

Question 32

what is the difference between fraternal twins and identical twins

Answer 32

identical twins come from the same egg and have identical DNA, while fraternal twins come from two different eggs and have different DNA like any other siblings.

Question 33

fraternal twins -
identical twins -

Answer 33

fraternal twins - dizygotic (DZ)
identical twins - monozygotic (MZ) - natural twins

Question 34

Genes related to these functions can affect
longevity control

Answer 34

○ Immune system functioning
○ Insulin secretion and glucose
metabolism
○ Response to stress
○ The cell cycle
○ DNA repair
○ Lipid (including cholesterol)
metabolism
○ Nutrient metabolism
○ Production of antioxidant enzymes