chapter 27 sections 1 & 2 chapter 37 section 1. over 1 million different kinds of animal...
TRANSCRIPT
INTRODUCTION TO ANIMALS
Chapter 27 Sections 1 & 2Chapter 37 Section 1
General Features of Animals
Over 1 million different kinds of animal species
Common features Heterotrophy Mobility Multicellularity Diploidy Sexual Reproduction
Heterotrophy
Animals are heterotrophs They can not make their own food
Most animals move from place to place looking for food
Once food is located it is eaten and digested by the body
Mobility
Animals can perform rapid, complex movements
They move by muscle cells that contract
MULTICELLARITY DIPLOIDY
Animals have multiple cells
Examples: Skin cells, hair cells, muscle cells, kidney cells
Adult animals have two copies of each chromosome
One set from the father and one from the mother
Sexual Reproduction
Almost all animals reproduce sexually by producing gametes (sex cells)
Female eggs are much larger than male sperm
Body Symmetry
Refers to an animals body shape Asymmetrical – irregular in shape Radial symmetry – have body parts arranged
around a central axis Bilateral symmetry – body design in which
there are distinct right and left halves
Body Functions
Digestion Food is broken down
Respiration Animals breathe (lungs, gills)
Circulation Blood is moved throughout the body
Nerve Impulses Messages are carried throughout the body
Support Framework for the animal
Excretion Waste removal
Reproduction
Sexual New individual is formed from the union of
male and female sex cells Asexual
Does not involve the fusion of sex cells
Levels of Cellular Organization
Organism Organ System Organ
Tissue
Cell
Cells
Many different kinds of cells in the body Skin, muscle, hair, cardiac (heart), etc
Stem Cells Cells that have the potential to develop into
any type of cell Research is being done to use stem cells to
repair damaged tissue
Tissues
A group of similar cells that work together to perform a specific function.
Epithelial Lines the body
Nervous Carries information throughout body
Connective Supports, protects, insulates body
Muscle Responsible for movement
Organ Systems
Two or more types of tissues working together to perform a specific function
Circulatory – transports nutrients, wastes, etc Digestive – breaks down food Endocrine – regulates body Excretory – removes wastes Immune – fights disease Integumentary – (skin) – protects body Muscular - movement Nervous – controls and regulates body Reproductive – produces offspring Respiratory – moves air Skeletal – protects and supports body
Body Cavities
Cranial – holds the brain Thoracic – upper chest (lungs, heart,
protected by rib cage) Spinal – down center of back, holds spinal
cord and nerves Abdominal – digestive organs (stomach,
gall bladder, liver, pancreas)
Body Cavities
Endothermy
Humans are endotherms, like all mammals.
Humans maintain a constant body temperature of 37ºC (98.6ºF)
The human body uses a great deal of energy to maintain a constant body temperature.