Lesson 1 Flashcards
Animals have 4 features
- Multicellular
- heterotrophic
-eukaryotes - have tissue that develop from embryonic layers
Cleavage
- the zygote undergoes a succession of mitotic cell divisions (without cell growth between the divisions)
- leads to the formation of the blastula
Blastula
-after cleavage- it is a hollow mass structure in the form of a ball
-gastrulation comes after
Gastrulation
- One end of the embryo folds inwards, expands, and eventually fills the blastocoel, producing layers of embryonic tissues; the ectoderm (outer layer), and the endoderm (inner layer)
- Layers of embryonic tissues that will develop into adult body parts are produced
- Ends with a gastrula
larva
-A sexually immature form of an animal that is morphologically distinct from the adult
-usually eats different food
- may have a different habitat than the adult, as in the case of the aquatic larva of a mosquito dragonfly
Metamorphosis
Animal larvae eventually undergo metamorphosis, a developmental transformation that turns the animal into a juvenile that resembles an adult but is not yet sexually mature.
What are the 6 stages of early embryonic development in animals?
- Cleavage … (eight cell stage)
- Blastula
- Gastrulation
- Gastrula
- Larva
- Metamorphosis
What is the cavity inside the blastula called?
blastocoel
Cross section of the gastrula
- the pouch formed by gastrulation, called the archenteron, opens to the outside via the blastospore
- the endoderm of the archenteron develops into the tissue lining the animal’s digestive tract
Which animals do NOT have Hox genes?
sponges
Animal development is controlled by a similar set of ____across a broad range of taxa.
hox genes
Hox genes
regulate the formation of the posterior-anterior (front-to-back) axis, as well as other aspects of development
How many extant species of animals are identified?
1.3 million
Ediacaran biota (neoproterozoic era 1B- 542M years ago)
an early group of soft-bodied multicellular eukaryotes (dates from 560 million years ago)
earliest known macroscopic animals
Cambrian explosion
another wave of animal diversification around 535-525 million years ago, during Cambrian period of the paleozoic era
most of the fossils from the Cambrian explosion are ___.
bilaterians
bilaterians
an enormous clade whose members have a two-sided or bilaterally symmetric form and a complete digestive tract (mouth and anus).
Why is the Burgess Shale important?
This site preserved fossils from the Cambrian period.
body plan
A particular set of morphological and developmental traits integrated into a functional whole-the living animal
radial symmetry
ex: sea anemone (phylum Cnidaria)
does not have a left or right side. Any imaginary slice through the central axis divides the animal into mirror images.
Bilateral symmetry (they have brains)
ex: lobster (phylum Arthropoda)
has a left and right side. Only one imaginary cut divides the animal into mirror-image halves.
diploblastic animals- which tissues do they have (2)? And which phyla (1)?
Cnidarians and a few other animal groups that only have the ectoderm and endoderm
Triploblastic
Having a mesoderm. Most bilaterally symmetrical animals are triploblastic. ex vertebrates, arthropods, and flatworms.
mesoderm
forms the muscles and most other organs between the digestive tract and the outer covering of the animal
body cavities définition and function?
Fluid-filled spaces located between different tissue layers.
Functions include:
1structural support for the body,
2.formation of an internal transport system to supply nutrients,
3.allow efficient gas exchange,
4.and remove waste
What are the body cavities of triploblastic animals? (3)
- Coelom
- Hemocoel… fluid = hemolymph
- Compact
What does the archenteron become?
the gut
What are the 3 characteristics that define animals?
- Nutrition
- Cell structure and specialization
- Reproduction and development
Animal’s nutritional mode?
Heterotrophs; ingest organic molecules and digestive enzymes produced within specialized cavities (mouth, stomach, and small intestine), digest them down to bits small enough to be absorbed across epithelial cells
- they CANNOT make their own organic molecules
- they obtain their molecules from the food that they ingest and digest in their bodies
which tissues are defining characteristics of animals? (2)
- Nervous tissue
- Muscle tissue
What are the cell structure and specialization of animals? (4)
- eukaryotes
- have no cell walls
- bodies are held together by structural proteins such as collagen!
- nervous tissue and muscle tissue are defining characteristics of animals
What is an animal? (4)
- how they acquire and assimilate nutrients
- the presence of molecules and tissues that are exclusive to animals
- their mode of sexual reproduction
- the presence of hox genes that determine their embryonic development
are plants photoautotrophs?
are they unicellular or multicellular?
- yes, using the energy from the sun, plants convert carbon dioxide into molecules of glucose.
- multicellular
are fungi heterotrophs or autotrophs? are they mostly unicellular or multicellular?
- heterotrophs; secreting digestive enzymes directly into their environment. These digestive enzymes break down complex organic molecules and digest them down to soluble products, small enough to e absorbed across the hyphal cells.
- mostly multicellular
a single hox gene set contains…
13 genes
how many sets of hox genes to vertebrates have vs invertebrates?
vertebrates= 4 sets of 13 genes
invertebrates = 1 set of 13 genes
Which phyla have radial symmetry? (2)
- Ctenophora 2.Cnideria
which part of the gastrula becomes the alimentary canal (the lining of the digestive tract)?
- the endoderm of the archenteron
What does the ectoderm develop into? (2)
- Nervous tissue, sensory system
- Epidermis of the skin
What does the endoderm develop into? (4)
- Epithelial cells lining the digestive tract and accessory organs, digestive organ system (liver, pancreas).
- Epithelial lining of respiratory, excretory and reproductive tracts and ducts
What does the mesoderm develop into? (4)
- Dermis of the skin
- skeletal and muscular systems
- circulatory and lymphatic systems
4.Excratory and reproductive systems
What is cephalization?
the clustering of neurons and sense organs
What is involved in body plans? (4)
- type od symmetry
- Embryonic tissues
- body cavity
- embryonic development
Why is the Cambrian period important in biology? (4)
First appearance of
1. hox genes
2. collagen
3. muscle tissue
4. nervous tissue
The exaggerated surface areas in mammals include? (3) and what are their functions? (3)
- The gut -> absorbs nutrients
- Lungs -> gas exahnge
- kidneys -> waste removal
what does the lining of the small intestine have to expand the surface area for nutrient absorption?
finger-like projections called villi.
4 types of tissues within the animal kingdom?
- Nervous tissue
2.Muscle tissue
3.Connective tissue - Epithelial tissue
What are the 5 types of epithelial tissues?
- Stratified squamous epithelium
- cuboidal epithelium
- simple columnar epithelium
- simple squamous epithelium
- pseudostratified columnar epithelium
What is the function of the simple columnar epithelium lining the small intestine?
produce enzymes to digest nutrients
animals with bilateral symmetry are also known to be …?
Triploblastic (having the 3 germ layers)
simple squamous epithelial cells? where are they found in animals?
the alveoli in the lungs are lined with them
where are simple columnar epithelium found?
found where secretion or active absorption is important. Ex: Lines the intestines, secreting digestive juices and absorbing nutrients.
where is stratified squamous epithelium found?
The lining of the oral cavity- since cells are always replaced from the basal surface.
How can we differentiate between protostome and deuterostome development? (3)
- By differences in cleavage
- coelom formation
- the fate of the blastospore.
where is simple squamous epithelium found?
Found in the alveoli of the lungs - these very flat cells provide a moist thin surface for gas exchange
What type of cleavage do protostomes go through?
spiral and determinate cleavage
Once absorbed into the epithelial cells, the digested food molecules move out from the basal surface and enter the ….?
Lymphatic or circulatory system
what is the function of connective tissue?
physical and immune protection, movement, support, storage, and transport
what type of tissue is the dermis?
a loose connective tissue beneath the epidermis
what is the function of the dermis? (2) (loose connective tissue)
- support the epidermis
- physical and immune defense
What is found within the dermis tissue? (loose connective tissue)
- Fat cells
- Mast cells (cells of the immune system)
- Macrophages (cells of the immune system)
- Collagen fibers
- Elastic fibers
- Reticular fibers (anchor the tissue in place)
all suspended in the matrix
what is Fibrous or dense connective tissue composed of?
mostly collagen, which serves to anchor skeletal muscle in the form of tendons and to connect bones at joints in the form of ligaments
what is beneath the dermis?
A layer of adipose tissue- mostly made of adipocytes that function to store fats
Most tissues including the dermis and adipose tissue are…?
vascularized
What type of cleavage do deuterostomes go through?
radial and indeterminate
What is the coelom formation of protostomes?
Forms from splits in the mesoderm
What is the coelom formation of deuterostomes?
forms from mesodermal out pocketings of the archenteron
What is the fate of the blastospore of protostomes?
Mouth forms from the blastospore
What is the fate of the blastospore of deuterostomes?
Anus develops from blastospore
blood contained in blood vessels is a type of ….. carrying red and white blood cells, nutrients, and waste in a liquid matrix to support the functioning of all body cells
Connective tissue
In bones, osteoblast cells produce collagen fibers which are hardened by… (3)
- Phosphorus
- Calcium
- Magnesium
What type of cells produces cartilage? Where are they embedded?
- chondrocytes
- rubbery matrix
Does cartilage contain blood vessels?
no, it is avascular- meaning it does not contain blood vessels.
which muscle tissue is voluntary?
skeletal muscle tissue
which muscle tissue is involuntary?
smooth muscle and cardiac muscle
what is the function of skeletal muscle?
to move the skeleton
what is the function of smooth muscle?
wrap around blood vessels and control blood flow to specific organs. As the smooth muscles contract, blood flow is reduced. Smooth tissue also empties the bladder and controls peristalsis of the gut.
what is homeostatic control?
The process of maintaining stability of the internal condition
What is negative feedback?
The mechanism responsible for maintaining homeostasis
What is positive feedback?
The mechanism that allows physiological responses to run their course to completion
What is the definition of heat?
Heat is defined as the transfer of kinetic energy from one particle to another.
What are the 3 types of ways heat can occur?
- Conduction
- Convection
- Radiation
What is the definition of conduction?
heat transfer across a stationery medium with a temperature gradient. OR the direct transfer of thermal motion (heat) between molecules of objects in contact with each other, as when a lizard sits on a rock.
What is convection?
the transfer of heat by the movement of air or liquid past a surface, as when a breeze contributes to heat loss from a lizard’s dry skin or when blood moves heat from the body core to extremities.
What is radiation?
The emisson of electromagnetic waves by all objects warmer than absolute zero. Ex: a lizard absorbs heat radiating from the distant sun and radiates a smaller amount of energy to the surrounding air.
what is the source of heat for endotherms?
Internal
What is the source of heat for ectotherms?
external
Do homeotherms have a narrow or wide range of temperatures?
Narrow
Do poikilotherms have a narrow or wide range of temperatures?
wide
are animals that generate their own internal source of heat and maintains a constant body temperature a thermoregulator or thermoconformers?
thermoregulators
are animals that derive their source of heat from their environment and can tolerate a wide range of internal temperatures a thermoregulator or thermoconformers?
thermoconformer
what are animals that derive their heat externally and keep a relatively constant internal body temperature?
ectothermic homeotherms
what are animals that derive their heat from metabolism and can tolerate a wide range of interal body temperatures?
endothermic poikilotherms
Place these in order:
1. Body temperture increase
2. thermostat in hypothalamus activates cooling mechanisms
3. blood vessels in skin dialate; capilarries fill with warm blood. heat radiates from surface. also increases conductive heat loss
4. sweat gkads secrete sweat, which evaporates cooling the body
5.Body temperature decreases.
1, 2, 4,3,5
BMR = body mass raised to the power of 3/4
basal metabolic rates
