Biology Exam 3- Animals

All animals share similarities in the ways in which they:

- Exchange materials with their surrounding
- Obtain energy from organic molecules
- Synthesize complex molecules
- Reproduce themselves
- Detect and respond to signals in their immediate environment

Levels of animal organization

cellular, tissue, organ, organ system

Phylum Porifera (Sponges)

What is an example of animals at a cellular level?

Phylum Cnidaria and Phylum Ctenophora (2 jellyfishes)

What is an example of animals at a tissue level?

Phylum Platyhelminthes (flatworms)

What is an example of animals at an organ level?

advanced animal groups

What is an example of animals at an organ system level?

tissues

Cells with similar properties group to form

organs

Tissues combine to form

organ systems

Organs are linked to form

- Epithelial Tissue
- Connective Tissue
- Muscle Tissue
- Nervous Tissue

What are the four main tissue types?

Epithelial Tissue characteristics

- Sheets of densely-packed cells that:
- Cover the body or enclose organs
- Line the walls of body cavities and organs
- Specialized to protect and to secrete/absorb ions and organic molecules
- Cells have a variety of shapes
- All are asymmetrical or polarized
- One side rests on basal lamina (basement membrane) and other faces environment
- Can function as selective barriers

single layer of flattened cells

the simple squamous epithelium is a

single layer square cells

the simple cuboidal epithelium is a

single layer of rectangular cells

the simple columnar epithelium is a

1 cell thick with all at basement membrane

the pseudostratified columnar epithelium is

stretchable tissue

the transitional epithelium is

secretion/absorption

ALL epithelial tissues are involved in

Connective tissue functions

- Connect, surround, anchor, bind and support
- Provides scaffold for attachment (support)
- Protects and cushions
- Mechanical strength
-Transmit information
- Transport

Types of Connective Tissue

- blood
- adipose
- bone
- cartilage
- loose
- dense

transport and protection

blood connective tissue is for

(fat) insulation, protection, support and energy

Adipose connective tissue is for

support and protection

Bone connective tissue is for

support and flexibility

Cartilage connective tissue is for

holds internal organs in place

Loose connective tissue

strength and support

Dense connective tissue is for

Cells specialized to contract, generating mechanical force

Muscle Tissues are

* Skeletal Muscle
* Smooth Muscle
* Cardiac Muscle

Types of Muscle Tissues

Attached to bone or exoskeleton for locomotion; striated, elongated fibers ; voluntary control

Skeletal Muscle

Surrounds tubes and cavities for propulsion of contents; flattened cells ; involuntary control

Smooth Muscle

Only in the heart ; striated elongate fibers ; involuntary control

Cardiac Muscle

- Complex networks of neurons (nerve cells)
- Initiate and conduct electrical signals from one part of the animal's body to another

Nervous Tissue

-Initiate new electrical signals
-Stimulate muscle cells to contract
-Stimulate glandular cells to release chemicals

Electrical signals produced in one neuron may stimulate or inhibit other neurons to

-part of the nervous tissue
-provide metabolic support, maintenance, ion balance, and cleaning for the neurons, production of new glial cells and neurons

Neuroglial cells

Composed of 2 or more kinds of tissues
May form sheets or tubes, layers, bundles, or strips

Organs

different organs work together to perform an overall function

Organ system

highly conserved family of genes with homologs in all animals that control body plans

Hox genes

Process of adjusting to the external environment and maintaining a stable internal environment

Homeostasis

Skin, all accessory structures

Integumentary System

- Protection from abrasion
- Protects against water loss
- Barrier to disease causing pathogens
- Protection from U.V. light
- Temperature regulation
- Contains sensory receptors (*mammals most advanced sensory receptors)
- Excretion (limited)

Functions of Integumentary System

Largest organ

Skin is the \_________________ of vertebrates

-Epidermis (outer layer)
-Dermis (inner layer)

Layers of skin

Outer layer
Thinner
Stratified squamous epithelium (mostly)

Epidermis

epidermis ; dermis

Nutrients diffuse into \_____________ from the \________

- Langerhans Cells
- Melanocytes
- Merkel Cells
- Keratinocytes

Cell types in the Epidermis

Defensive cells

Langerhans Cells

Produce pigment melanin
Skin coloration
Protection from U.V. light

Melanocytes

Merkel Cells

touch receptors

Keratinocytes

Primary cell type
Produce insoluble protein, keratin

Keratin fills cytoplasm and impairs nutrient diffusion.....

cells die

inside to outside

Amount of keratin increases from..

Inner layer of skin; thicker than epidermis
Highly vascularized
Contains sensory structures, vessels, nerves, glands
Origin of hair, feathers, scales of vertebrates

Dermis

Meissner's corpuscles and Pacinian corpuscles

Sensory structures in dermis

light touch (around hair ; base follice)

Meissner's corpuscles

deep pressure and vibration

Pacinian corpuscles

Sweat Glands

Temperature regulation
Produce sweat (primarily water)/ waste ions
Release of heat

2.5 million

How many sweat glands are in the body?

Sebaceous Glands

Large on face, neck, and upper chest
Produce sebum: lubricates and softens hair and skin

lubricates and softens hair and skin

Sebum

palms and soles

Sebaceous glands are found all over the body except...

Hypodermis (subcutaneous layer)

Lies beneath dermis
NOT a layer of skin
Contains much adipose (fat) tissue

body contour, insulation, energy storage, support for skin

Functions of the hypodermis

thicker

Females have a \_______________ layer of adipose tissue than males

Nutrients

any substance taken in by an organism that is needed for survival, growth, development, tissue repair, or reproduction

Nutrition

process of consuming and using food and nutrients

Animals receive nutrients by

consuming food

Heterotrophs

(ingest feeders)
Cannot manufacture own food
Require already synthesized organic compounds of plants or other animals

heterotrophs

Animals are

survival
maintenance
growth
reproduction

Hierarchy of nutrient use

blind gut and tube-within-a-tube

2 types of Gut tracts

Blind Gut

No cavity between gut and body wall
One opening
Primitive form

Tube-within-a-tube

Flow through digestive tube
Body cavity between gut and body wall
Separate openings (mostly)

Hydrolases

cleave bonds on molecules with the addition of water

Digestive enzymes are classified as

hydrolases

Carbohydrases

digestive enzyme that breaks down carbohydrates

Proteases

digestive enzymes that break down proteins into amino acids

Lipases

digestive enzymes that break down lipids

Nucleases

digestive enzymes that break down nucleic acids

1. Ingestion: food is taken into the body and moves into a digestive cavity (called the alimentary canal)
2. Digestion: food is broken down into smaller molecules (chemical; mechanical)
3. Transport
4. Absorption: ions, water, and small molecules diffuse or are transported into the circulatory system (nutrient absorption)
5. Egestion: undigested materials and other wastes are passed from the body
(Elimination OR Excretion)

Food processing occurs in five steps...

Digestion

food is broken down into smaller molecules (chemical; mechanical)

Ingestion

food is taken into the body and moves into a digestive cavity

Absorption

ions, water, and small molecules diffuse or are transported into the circulatory system

Egestion

undigested materials and other wastes are passed from the body

Alimentary Canal

digestive tube that extends from the mouth to the anus

- Carbohydrases
- Proteases
- Lipases
- Nucleases

Digestive Enzyme Types

epithelial cells

The alimentary canal is lined by

smooth muscle in walls

The alimentary canal contains

Synthesize and secrete digestive enzymes (simple epithelium)
Secrete hormones
Transport digested material

Epithelial cells in the alimentary canal function to

epithelial and glandular cells

Lumen of the GI tract is lined by

mucus

Secretory cells release a protective layer of \__________ in the GI tract

acid, enzymes, water and ions

Glands release \___________ in the GI tract

Epithelial cells linked by tight junctions and surrounded by layers of tissue made of smooth muscles, neurons, connective tissue, and blood vessels

Structure of GI Tract

sight and smell of food, presence of food in tract

Neurons in the GI tract are activated by

- Buccal cavity
- Ingestion site and digestion site (chemical & mechanical)
- Jaws, teeth, cheek muscles, tongue, salivary glands, saliva (⍶-amylase)
- Pharynx

Region of Reception

Buccal cavity

mouth and accessory structures

Pharynx

back of mouth cavity,
point where digestive and respiratory systems cross paths

Region of Conduction

Esophagus, conducts food from pharynx to stomach through peristalsis

Esophagus

tube carrying materials from mouth cavity to rest of the alimentary canal

Peristalsis

rhythmic, wave-like contractions which propel food forward in G.I. tract

Region of Storage and More Digestion

- stomach (sac-like organ evolved for storing food)
- muscular nature helps break up food (partial protein digestion)
- regulates rate of emptying into small intestine

Secretions in the Stomach

hydrochloric acid and pepsinogen