WELCOME TO BIO 101!

Life Science

The Human Environment

"The role of the infinitely

small in nature is infinitely

large"

-Louis Pasteur

Types of Nervous Systems

Central

Nervous

System

Peripheral

Nervous

System

Central Nervous System Function

• Controls

fundamental

functions

• Generate emotions

• Decoding sensory

input

• Coordinating motor

activity

Peripheral Nervous System Function

• Sensory Neurons

– Carry information from

sensory organs to the

central nervous

system

• Motor Neurons

– Carry information from

the CNS to muscles

and glands

• Somatic nerves

– Voluntary

• Autonomic nerves

– Involuntary

Sensory Input

• Chemoreceptors

• Photoreceptors

• Mechanoreceptors

A receptor must bind a stimulus in order to stimulate the

neurons that send information to the brain. The brain then

interprets the signal and responds to it.

Chemoreceptors: Taste

• Five primary different tastes

– Bitter, Sour, Salty, Sweet, Unami

• Binding of molecules depolarizes

cell

• Depolarization transferred to neuron

Chemoreceptors: Smell

• Olfactory cells in the nasal cavity bind

molecules

• This causes depolarization of the

olfactory cells

• Depolarization transferred to the neuron

in olfactory bulb

Photoreceptors: Vision

• Light passes through the cornea and lens and is concentrated on the retina

• Muscles attach to the lens allow it to change shape and affect where the light is focused

Normal Sight

Near Sighted - unable to see

objects far away

Far Sighted - unable to see that are near

Two Types of Photoreceptors

• Rods

– Black-white

vision

– Useful in low

light

– Found

throughout retina

• Cones

– Color Vision

• Receptors have a pigment (Rhodopsin) that decomposes

when struck by light of proper wavelegth

• This causes depolarization of the nerve cells

• Depolarization transferred to a ganglion cell and then to the

brain

Pigment Molecules

• The full Ishihara test

consists of a set of 38

plates and tests in-

depth for color

blindness. The plates

here are a small

representative sample

of the whole, but will

help spot the most

common forms of

colorblindness.

Ishihara Test for Color Blindness

Mechanoreceptor: Hearing

– Outer ear

• Pinna

• Auditory canal

– Middle ear

• tympanic

membrane

• oval and round

windows

– Inner ear

• Semicircular

canals, Vestibule,

Cochlea

Sounds Old People can't hear..:0)

Mechanoreceptor: Touch

• Pressure

• Temperature

• Pain

Motor Output

• After taking in

information from the

sensory organs, the

brain may respond via

motor output

• The nervous system

can cause:

– Muscles to contract

– Glands to secrete

Take Home Message

• Positive and negative feedback loops allows

the nervous system to help maintain

homeostasis

• The central nervous system integrates the

information that it receives from, and

coordinates the activity of, all parts of the

bodies

• The peripheral nervous system connects the

central nervous system (CNS) to the limbs

and organs

Reproduction

What makes something alive?

• Unique Structural

Organization

• Metabolic Processes

• Control Processes

• Generative

Processes

• Responsive

Processes

✔

✔

✔

Generative Processes

• Increase in size

of an organism

• Asexual

reproduction

• Increase in

number of

organisms

– Sexual

reproduction

– Asexual

reproduction

Sexual

• Different individuals,

from the same

species, create and

offspring

• Genetic information is

contributed from at

least two individuals

• Offspring has half the

genetic make-up from

each parent.

Asexual

One individual creates an identical copy of itself

There is NO contribution of genetic material from another individualgenetic make-up from each parent.

• Different individuals,

from the same

species, create and

offspring

• Genetic information is

contributed from at

least two individuals

• Offspring has half the

genetic make-up from

each parent.

Primary Sexual

Characteristics

Secondary

Sexual

Characteristics

Sexual

Primary Sexual

Characteristics

Secondary

Sexual

Characteristics

Directly Necessary for Reproduction

The Reproductive System

Primary Sexual

Characteristics

Secondary

Sexual

Characteristics

Not Directly Necessary for Reproduction

Sexual Reproduction

• Primary sexual characteristics are

REQUIRED for sexual reproduction to

occur

• Secondary sexual characteristics are

IMPORTANT for sexual reproduction, but

are not REQUIRED

PHYSICAL

CHARACTERISTICS

Enlarged Breasts

Growth of Body Hair

Round Face

Widening of the Hips

Small Waist

Distribution of fat

Buttocks

Thighs

Hips

Growth of Body Hair

Facial Hair

Enlarged Larynx

Deep Voice

Increased Stature

Square Face

Broad Shoulders

Low Body Fat

The Padaung

Foot Binding

Female

Male

Female

Male

Sexual Reproduction

• Primary sexual characteristics are

REQUIRED for sexula reproduction to

occur

• Secondary sexual characteristics are

IMPORTANT for sexual reproduction, but

are not REQUIRED

BEHAVIOR

Successful Male Female that can

Produce Offspring

BEHAVIOR

Birds of Paradaise Human Male Dance

BEHAVIOR

Male dance moves that catch a woman's eye

http://pubmedcentralcanada.ca/pmcc/articles/PMC3061152/pdf/rsbl20100619.pdf Nick Neave,*, Kristofor McCarty1, Jeanette Freynik2, Nicholas Caplan1, Johannes Hönekopp1

and Bernhard Fink2

April 23, 2011

Good Dancer Bad Dancing

Biology Letters

Human Sexual Reproduction

46

Chromosomes

23

Chromosomes

46

Chromosomes

46

Chromosomes

Meiosis

• Cell division which

creates gametes.

– Ovaries make Ovum

(egg)

– Testes make Sperm

• Contains only half

of the genetic

make-up

• Necessary for

sexual reproduction

Life History Strategies

• Reproduce at an early age

• Have A LOT of offspring

• Short generation time

• No Parental Care

• Are Short Lived

Reproduce late in life

Have a few offspring

Long generation time

A lot of Parental Care

Are Long Lived

Oyster Ape

Modes of Sexual Reproduction

• Oviparous

• Ovo-viviparity

• Vivipary

Modes of Sexual Reproduction:

Oviparous • Embryos

develop in eggs

• No emryonic

development

inside mother’s

body

Modes of Sexual Reproduction:

Ovo-viviparous

• Embryos

develop in eggs

• Egg stays in

mother’s body

during embryo

development

• Hatch in

mother’s body

Eggs

• Yolk is stored food to be used during

development

Developing from an Egg

• Larval stage

– Utilize different food

source than adults

Modes of Sexual Reproduction:

Viviparous

• Embryos

develop inside

mother’s body

• Leads to live

birth

• Feed by mom

directly

• No shell needed

Viviparous Embryo

• Different individuals,

from the same

species, create and

offspring

• Genetic information is

contributed from at

least two individuals

• Offspring has half the

genetic make-up from

each parent.

Sexual

• One individual creates an identical copy of itself

• There is NO contribution of genetic material from another individual

Asexual

Asexual Reproduction

• Budding – New individuals branch

off another individual

• Fragmentation – New individual forms

from a fragment of a parent

• Parthogenesis – New egg without sperm

(female only) • Plants, insects,

some snakes

Asexual Reproduction

• Budding – New individuals branch

off another individual

• Fragmentation – New individual forms

from a fragment of a parent

• Parthogenesis – New egg without sperm

(female only) • Plants, insects,

some snakes

Asexual Reproduction

• Budding – New individuals branch

off another individual

• Fragmentation – New individual forms

from a fragment of a parent

• Parthogenesis – New egg without sperm

(female only) • Plants, insects,

some snakes

Poecilia formosa

(Amazon molly)

Lampert K , Schartl M Phil. Trans. R. Soc. B 2008;363:2901-

2909

Summary • There are two types of sexual reproduction

• Asexual reproduction uses genetic information of one

individual to produce identical offpsring to the parent.

• Sexual reproduction combines genetic information of

individuals from the same species and produces an

offspring with a new genetic makeup.

• Primary and secondary sexual characteristics are

important in the success of sexual reproduction

• Several modes of reproduction occur depending on the

organism.

• The modes of sexual reproduction determine how an

embryo will develop