dev, genetics, motivation, personality, disorders

KA 124-175

sperm structure

head, midpiece, tail

acrosome

A vesicle at the tip of a sperm cell that helps the sperm penetrate the egg

head of sperm

*genetic region

midpiece of sperm

generates ATP from fructose and contains many mitochondria

tail of sperm

locomotor region; flagellum

zona pellucida

A thick, transpartent coating rich in glycoproteins that surrounds an oocyte.

fertilization steps

sperm bindingàacrosome reaction àcortical reaction àgenetic transfer

sperm binding

Sperm comes in contact with zona pellucida and releases acrosomes to digest it. Egg then releases other enzymes to prevent other sperm from binding

acrosome reaction

enzymes leak into zona pellucida and digest it. Sperm gets closer to plasma membrane of egg.

cortical reaction

-calcium ion released after penetration of sperm into egg

-calcium ions depolarize the membrane of the ovum

-prevents fertilization of ovum by multiple sperm cells

polyspermy

fertilization by more than one sperm

zygote

the fertilized egg; it enters a 2-week period of rapid cell division and develops into an embryo

morula

A solid ball of cells that makes up an embryo; in humans, this stage occurs within four days of fertilization.

Cleavage of zygote

The rapid mitotic division of a zygote that begins within 36 hours after fertilization

Produces a ball of cells called morula, which is the same size as original zygote so no G growth phase is occurring

trophoblast

outer cells of the blastocyst that secrete enzymes that allow implantation

Embryoblast

The inner cell mass of the blastocyst, which is the developing human organism.

blastocyst

stage of early development in mammals that consists of a hollow ball of cells

blastocoel

the fluid-filled cavity inside a blastula

amniotic cavity

cavity in which the fetus exists; forms early in gestation; fills with amniotic fluid to protect the fetus

hypoblast

forms yolk sac

epiblast

the outermost layer of an embryo before it differentiates into ectoderm and mesoderm.

bilaminar disc

two-layered disc (epiblasts and hypoblasts) that forms from the inner cell mass at the beginning of the second week

primitive streak

A groove on the surface of an early avian embryo along the future long axis of the body.

gastrulation

the process in which a gastrula develops from a blastula by the inward migration of cells

trilaminar disc

ectoderm, mesoderm, endoderm

Neurulation

development of the nervous system

notochord

A rod of tough, flexible material that runs the length of a creature's body, providing the majority of its support

neural plate

flat group of cells present in prenatal development that becomes the brain and spinal cord

neural groove

Groove resulting from further growth and thickening of the neural plate.

neural folds

Raised ridges in the neural plate that surround the deepening neural groove.

neural tube

a groove formed in the top layer of differentiated cells in the embryo that eventually becomes the brain and spinal cord

neural crest cells

Cells at the tip of the neural fold; this group of cells gives rise to many components of the peripheral nervous system.

blastocyst stage

zona pellucida is disintegrating while the endometrium lining is proliferating

apposition

blastocyst attached to the endometrium

outer trophoblasts divide into

endometrium

trophoblasts

getting larger and they start to fuse (syncitiotrophoblast) + cytotrophoblast (the ones that used to be trophoblast)

Synciotrophoblasts

form villi and the endometrium is growing (which is uterine blood)

form fetal blood vessels -which are close contact to uterine blood. Lines inside of uterine cavity -placenta

endoderm

GI tract tube (forms esophagus, small intestine, large intestine)+ lungs + liver + pancreas

mesoderm

form inner layers of skin, muscles, bones, cardiac muscles, kidneys, and bladder, ovaries/testes

ectoderm

outer layer of skin, sweat glands, hair skin, nervous system

gestation

growth process from conception to birth

gestation week

38-42 weeks

Trimesters of pregnancy

• 1st trimester: week 1-13
• 2nd trimester: week 14-26
• 3rd trimester: week 27-40

LMP

first day of last menstrual period

fertilization occurs when?

week 2

embryogenesis

The process by which a single-celled zygote becomes a multicellular embryo.

week 10

fetal development

Birth at 24 weeks

50% survival

birth after 23 weeks

rate of less complication decreases

birth at 40 weeks

full term

preterm

37 weeks

postterm

after 42 weeks

end of gestation

birth

reflexes

programmed physical reactions to certain cues that do not require any conscious thought to perform

2-4 months

raising head and chest

2-5 months

rolling over

5-8 months

sit without support

5-10 months

stand with support

6-11 months

-Gets to sitting position from prone

7-12 months

crawling

7-13 months

walk using furniture for support

10-14 months

stand alone easily

11-15 months

walk on own

back sleeping

reduce SIDS
sleeping on back makes it so children take alonger time to start crawling

gross motor skills

legs/arms. Develop before

fine motor skills

physical abilities involving small body movements, especially of the hands and fingers, such as drawing and picking up a coin

head to toe development

baby can lift head before they can crawl

how to speed up motor milestones

Lots of toys = motor milestones are quickly achieved

permanent reflexes

swallowing, breathing, coughing, blinking

breathing reflex

PERMANENT
Provides oxygen and expels carbon dioxide

swallowing reflex

reflex that enables the newborn baby to swallow liquids without choking

coughing reflex

triggered when food or liquids touch the vestibular or vocal folds.

blinking reflex

Causes the baby to close her eyelids in a protective motion when you tap her on the top of her head

pupillary reflex

both pupils constrict when light is directed at one eye

eyeblink reflex

shine a bright light or clap, they will close eyelids. Protects from strong stimulation

neonatal reflexes

unlearned and involuntary responses to a stimulus, often used diagnostically

rooting reflex

a baby's tendency, when touched on the cheek, to turn toward the touch, open the mouth, and search for the nipple

Babinski reflex

Reflex in which a newborn fans out the toes when the sole of the foot is touched
disappears at 12 months

Monro reflex

startle reaction. Fan out arms then back. Disappears in 4-6 month of age.

tonic neck reflex

(aka fencing posture)-

how when a baby's head is turned, the arm on that side straightens while the arm on the side that is opposite bends.

Disappears at 6 months of age.

galant reflex

when Skin is stroked, baby moves/swings to the side it was stroked. Disappears at 6 months.

Palmer Grasp Reflex

children closes their hands on anything that comes in their palm. Disappears at 3-4 months, then child grasps things voluntarily

sucking reflex

How a baby will suck on any object that is placed in its mouth. Disappears at 3-4 months

stepping reflex

Hold an infant upright and their feet touch a flat surface, they will start to step as if they are trying to walk. Disappears in first two months

swimming reflex

infants in water move legs/arms in a swimming motion. Involuntarily hold breaths. Allows a small infant to swim/float for a short period of time. Disappears at 6 months of age

puberty

2 yr long of sexual maturation (end of which you can reproduce)

Puberty starts for boys at ages

10-15

Puberty starts for girls at ages

8-13

first ejaculation

14 years old

first menstrual cycle

12/13 years old

primary sex characteristics

the body structures (ovaries, testes, and external genitalia) that make sexual reproduction possible

secondary sex characteristics

nonreproductive sexual characteristics, such as female breasts and hips, male voice quality, and body hair

early puberty in boys

Positive: stronger/taller (more athletic) popular/independent.
Negative: increase delinquency and alcohol use

early puberty in girls

negative effects
unpopular, withdrawn, low self-confidence, negative image, more long term problems, earlier sexual endeavors, unwanted attention

prefrontal cortex develops at what age

adolescence

global brain changes

Increase myelination (faster communication of neurons-faster connections b/t brain areas)
Increase in brain volume in early adolescence and then decrease later in adolescence

synaptic pruning

breaking down connections between certain neurons. Focus resources on the ones we use the most. What we do during our teenage users -shapes us for life.

behavioral genetics

the study of the effects of heredity on behavior

inherited trait

A characteristic that is passed from parent to offspring.

acquired trait

A trait that is not in your genes but is picked up from environmental factors.